Doctor's Note

What’s TOR? Make sure you go back and watch my “prequel” video Why Do We Age?

This reminds of the study I profiled in The Benefits of Caloric Restriction Without the Actual Restricting.

Methionine is another amino acid that may be associated with aging. See Methionine Restriction as a Life Extension Strategy to find out which foods to avoid in that case. Both leucine and methionine content may be additional reasons why Plant Protein is Preferable.

Other reasons why those eating plant-based diets may live longer:

 This all may help explain the results of Harvard’s Meat and Mortality Studies.

If you haven't yet, you can subscribe to my videos for free by clicking here.

To post comments or questions into our discussion board, first log into Disqus with your account or with one of the accepted social media logins. Click on Login to choose a login method. Click here for help.

  • Kaleb Rogers

    Awesome! Especially considering the beneficial effects plant-based diets have on telomerase!

  • HemoDynamic, M.D.

    Heavy side of relief!
    I thought I was going to have to do the crazy calorie restriction diet and turn into Ichabod Crane just get a few more years on this planet!
    Look out plants, I’m hungry!

    • Emoji for the win!

    • LOL! I don’t restrict calories at all now and I am enjoying my best health. I do eat a whole food plant based diet.

      • Jim

        When you say ” plant based diet” does that mean that it must be eaten raw, or can you use conventional cooking methods to prepare the plant to eat.

        • I eat mostly uncooked since I am drinking veggie or fruit juices, and eating fruits, salad, nuts throughout the day. (I blend my veggie and fruit juices, I don’t juice) For my last meal of the day I may have some quinoa, split pea soup, boiled plantains, black rice, or some kamut spirals. 115 dregrees is considered raw so those might be considered raw. I don’t believe you have to be completely uncooked or raw to be healthy, but most of your food should be to get the most nutrients out of your food. Stay away from frying.

          • Jim

            I appreciate you taking the time to respond.

        • george jacobs

          Plant based is not connected to cooked or raw. It just means you eat foods mostly from plants, not from animals. Mushrooms are not plants or animals.

        • SteveBillig

          The simple answers are: variety and enjoyment. The details are: in some cases, cooking enhances the availability of nutrients in food. In other cases, cooking damages the nutrients. My recommendation is: Don’t try to micromanage it. Eat some cooked, some fresh. And enjoy.

        • Lawrence

          Jim, Dr. Greger has a video on the best cooking method:

        • Plant based refers to the food and not how it is prepared. Cooking food enables us to absorb about 10-15% more calories. Cooking interferes with our ability to absorb some nutrients but facilitates the absorption of others. See some of Dr. Greger’s videos on the effects of cooking on various foods. You might start with: Bon Apetit!

        • Suzanne Dixon MPH RD

          A plant-based diet refers to a diet that is based predominantly on plant foods – legumes, nuts, seeds, vegetables, fruit, and whole grains – and includes both cooked and raw plant foods. Ideally, you should aim for variety, and this means not just variety in types of foods you eat, but also variety in preparation methods. This is because different preparation methods will affect how your body absorbs the hundreds to thousands of phyto-nutrients found in these foods. In general, most “gentle” cooking methods – stir frying, sauteing, or microwaving, for example – are excellent choices for most vegetables.

          If you want fine detail, be sure to check out Best Cooking Method. But keep in mind, the study mentioned in the video considered how cooking methods affect antioxidant levels. There are dozens of nutrients that have activities far beyond being mere antioxidants

          If you like REALLY fine detail, you may enjoy Polyphenols: food sources and bioavailability. As noted in this article, polyphenols may have important effects on human health because they are metabolized by the same pathways as xenobiotics and endogenous hormones. This may, in turn, decrease the risk of neurodegenerative diseases, cardiovascular diseases, and hormone-dependent cancers. In this regard, polyphenols may be affecting health through pathways unrelated to antioxidant activity, and considering only the effects of cooking methods on antioxidant levels would miss these considerations.

          In the end, I believe it’s important not to get too bogged down in what I refer to as “minutia,” or the extremely fine details, which, in the context of balanced, varied, healthy plant-based diets, are inconsequential. Some of the mysteries of how and why plants improve human health may never be solved, but we do know that eating these foods is one of the best things you can do to decrease chronic disease risk!

        • The people in the studies cited cook their food. Some nutrients are made more bioavailable through heat.

    • Michael Roidsky
  • Lauren

    Super interesting. What about plant foods high in leucine, like spirulina or plant protein sources?

    • Good question. So I checked Nutrition Data…

      …and aside from soy protein isolate, soy protein concentrate, and spirulina, none of which Dr. Greger recommends, I had a hard time finding any other plants with a high leucine content. I had to go through pages just to find tofu and seaweed, both of which were at almost #300 on the list.

      Search for soy and spirulina for Dr. Greger’s reports on those foods.

      If I recall properly, I believe Dr. Greger recommended limiting traditionally processed soy (not veggie burgers) to one serving a day.

      • Laloofah

        It was 3-5 servings of soy a day. Here’s the video:

      • Paul

        The numbers I’ve seen suggest that peanuts and almonds have comparatively high leucine levels, which presents a bit of a contradiction with the previous research suggesting the nut consumption is associated with greater longevity.

        • Interesting. I’d love to see your data source.

          I’m also wondering if traditional food combining for “complete” proteins, like rice and beans, peanut butter on whole wheat bread, etc. negate the lowered leucine effect.

          • Timar

            Well, if you look at the USDA database without vegan glasses ;-) there are actually plenty of plant foods high in leucine, isoleucine or methionine.

            Dried peas are among the top sources of leucin, they provide just as much as meat. Nuts are but a little bit lower, proving similar amounts as eggs or cheese.

            The two top-sources of methionin are plant-based too: brazil nuts and sesame seeds. You don’t usually eat very much of those, though.

          • Darryl

            Grams leucine / 100 g (as in this video) is not a particularly practical measure, compared to g leucine / kcal. That said, consider the diet of two hypothetical 60 kg adults consuming 2400 calories. One with a diet comprised entirely of potatoes would ingest 3.4 g leucine, while the another with a diet entirely of skim milk would 22.9 g. As their leucine requirement is 2.34 g according to the WHO, the extreme McDougaller is getting 144% of the requirement, while the dairy fanatic is getting 978% of the requirement.

            With regard to the video, mTOR may be the main cellular regulatory hub downstream of IGF-1: they’re two links in a branching chain, rather than separate strands. The full pathway is in an earlier comment here, while this is an abbreviated diagram of where leucine interacts wiith insulin/IGF-1/mTOR signalling (mTORC1 is the mTOR complex associated with growth signalling):


          • guest

            Wow, thanks once again for this information darryl! I sometimes can get a grasp on how the chemistry works by reading various papers, but the graph you have here makes it much easier to see the whole picture. I’m waiting for the days of genetic manipulation to modify directly these pathways.

          • Arjan den Hollander.

            LoL 2 60 kg adults. Is that the norm now?

            I mean a 60 kg male is a skeleton m8.
            Women can still have babies weighing that but come on!

            In your world women would have great difficulties surpressing the urge to shop for seed outside of the relationship. Their uncontious brain would have them throw themselves at the first meat eating male doing some repair work around the house.

          • Darryl

            60 kg is nowhere near the norm in the developed West, but isn’t too far from the world adult average of 62 kg. Also picked to be somewhat inclusive of the fairer (and majority) sex.

          • Ah, the dose makes the poison. How does my question about combining for complete proteins figure in a real life situation?

          • Darryl

            As you’re perhaps aware, food combining for a complete amino acid profile each meal is unneccessary, as the body stores of each essential amino acid are generally enough to get through 24 hours. Vegans mosty just need to eat some higher lysine (not leucine) foods like legumes sometime each day to ensure adequate lysine, and the rest takes care of itself.

            So, practically looking a real life diets, vegans likely consume 150-250% of the leucine requirement, while most omnivores and ovo-lacto-vegetarians are likely around 400-600% of the requirement.

          • Yup. On paper, I know that. But food sensitivities cut down on the amount and variety of plants I can eat. That forced decrease in intake caused me some protein challenges, so any little but of help I could give my body I tried, not to mention issues of flavor and convenience. It makes sense for me to mix my black-eyed peas and lentils with a starch, mainly wild rice or yellow corn.

            Eventually I had to give in and add a little animal protein to my diet à la Fuhrman. First time in 20 years. I was not a happy camper.

          • Sebastian Tristan

            If you have food allergies, check out a treatment called NAET. It helped me relieve/eliminate most of mine.

          • Thanks for the sales pitch. But NAET has a disclaimer on their website:

            NAET does NOT claim to cure allergies or food, chemical and environmental sensitivities.”

            Acupuncture, kinesiology, and chiropractic. No thanks.

          • Sorry for the cynicism, Sebastian. I apologize for my curt response. Most alternative treatments, when scrutinized in quality peer reviewed studies demonstrate little benefit beyond placebo. Chiropractic has been proven to have benefits for lower back pain but not for any other maladies.

          • Sebastian Tristan

            No worries. I’m a fellow skeptic. When I speak of NAET, I speak from personal experience. I, my girlfriend and all our acquaintances who were treated by our acupuncturist/osteopath benefited from it. When I say benefited, I mean my allergies were 90% gone (for at least a year) from the first treatment. Yet, the skeptic that I am, I still didn’t believe in it. It took me 5-7 sessions to feel more at ease with it. As for acupuncture, still speaking from personal experience, it has helped me tremendously with joint issues due to exercising and typing (I work in an office).

          • Toxins

            If you have ever heard of Airrosti, they are soft tissue specialists that are chiropractors but with advanced training. They have a business model of trying to achieve healing in 3 visits or less. It sounds unreal and illegitimate at first, but its seriously incredible the work they do. I suffered shoulder impingement due to excessive rock climbing and a friend told me about Airrosti. I had been stagnating for a couple months in recovery and had seen 2 orthopedists and they gave me no help so out of desperation I decided to check it out. The Dr. there worked wonders on me, within 2 weeks I could climb hard routes with very little pain. There is a science behind it and its not gypsy, nor do they have the chiropractic model of returning to them forever, they want you healed asap so you dont ever have to return. They do every body part pretty much.

            I just thought I would say something about Airrosti because it has healed me. They do what the orthopedists cannot, which is surprisingly alot. They are also within departments at major hospitals around Houston where I live which further adds credibility to the outside eye.

          • Interesting, Toxins. Not sure what Airrosti can do for food sensitivities, but they’re a long walk from South Dakota. ;-P

            What do they do? massage?

          • Toxins

            Yes, completely unrelated to food allergies! They don’t massage, they do “manual therapy”, which is actually quite painful. The idea is to loosen the connective tissue, improve mobility, and then there is very specific physical therapy prescribed which maintains the work the Dr. did.

          • Sounds interestingly dangerous! How can you be sure it was the manipulation and not the physical therapy which did the trick for you? ;-P

          • Toxins

            Its definitely a mix of both, immediately after treatment you are instructed to try the physical activity depending on the severity of your injury. The orthopedists I went to gave me PT to do and it really was not helping at all, they couldn’t even diagnose me. Like I said, I would not have believed it myself if I hadn’t experienced it and seen many of my climber friends heal from it. Check out the Airrosti link in my first post for details. This is one of those moments for me that there doesn’t need to be scientific papers to prove its efficacy, the documented 94% patient improval rate and 88% resolution of injuries is enough for me. Most major insurances cover it.

          • Visited the website when you first posted it. Guess it’ll be awhile before they open an office in South Dakota. Any nutriceuticals involved?

          • Toxins

            No, none. Its all physical.

          • Timar

            As ever you are right, Darryl. It’s the whole IGF-1/Akt1/PI3K/mTOR-pathway (and the AMPK branch) we have to keep an eye on. It starts by improving insulin sensitivity in order to optimize postprandial glucose uptake and, as a consequence, minimize insulin signaling in the fasted state. Reducing IGF-1 by protein restiction is just another part of the plan.Then we should make sure to get plenty of all the phytochemicals which inhibit mTOR either directly, or more, often indirectly. It is not unlikely that the combined action of all those phytochemicals at different points on the signaling cascade excert a synergistic inhibitory effect. This could be the reason why plant protein may have a different effect on mTOR activity despite similar levels of leucine: in contrast to animal protein, it comes packed together with those phytochemicals.

          • We run into problems when we try to isolate the properties of individual nutrients because they react differently depending on the environment they are in. Aminos acids in meats react differently than amino acids in plant life because of there total nutrient makeup.

          • Yeah, wasn’t vegan glasses ;-) but mobile phone pagination fatigue. :-D

          • SteveBillig

            Exactly! an appropriate size 1 ounce portion of brazil nuts contains 323 mg of leucine. A modest 3 ounce portion of cooked beef contains 2,200 mg of leucine. More importantly, it’s best not to look for exceptions. You will always be able to find them. When you test a claim, look at the big picture. Is a plant-based diet lower in leucine than a diet that is high in animal protein? Yes, the devil is in the details, but the big picture is what is most important.

          • Paul

            I used data from the USDA, which reports peanuts at 1.54g of leucine per 100g.

            In terms of food combining, I’d be surprised if that had any effect, as the limiting amino acids in plant foods tend to be methionine and lysine, rather than leucine. That’s part of the reason I’m surprised by the conclusion of this article, as leucine is not one of the amino acids which tends to be proportionately low in plant food sources.

        • Nutrients in animals sources and plant sources don’t necessarily react the same way in the body. Campbell’s work showed an increased correlation between protein increasing from 10-20% of calories but soy and wheat protein at the same levels did not show the correlation. It is likely the leucine levels in meat are the problem. I love almonds an do eat a lot of them, but I don’t eat peanuts.

          • Paul

            That could well be the case, but that would indicate that leucine is not in itself the significant factor.

          • Yup. It is the leucine in meat protein.

          • Paul

            That statement would only make sense if the leucine in meat could be shown to be chemically different to the leucine in plants.

          • Really, that is the only way it would make sense? Why couldn’t it be something in the meat that interact with the leucine that causes leucine to be the problem, and that something might not be in plant based foods, or not to the same level.

          • Paul

            That could be the case, but that would contradict your assertion that it is the leucine in meat protein which causes the problem.

            You’re conflating two different possibilities:

            1 – The leucine in meat is the problem.
            2 – The leucine in meat is not the problem, but something else in meat creates a problem when it interacts with leucine.

            It is a very important distinction if somebody is assessing the risks of consuming isolated leucine.

            There are other possibilities which are also relevant when it comes to decision making:

            3 – Leucine in general causes the problem, but something else in plant based sources of Leucine provides a protective effect.
            4 – It’s has nothing to do with Leucine, but is caused by another substance or combination of substances.

            For the research underpinning this article to have practical use, we need to find out which of the possibilities it is.

          • I see it this way. Meat protein acts differently in the body than plant protein. Since the leucine in meat may be the issues and not the leucine in plant based foods then it is the leucine in meat that is the problem, Whether it is because of the way it interacts with other substances or not. Our approaches are a bit different, and yours appears to be scientifically driven. Mine is naturally holistically driven. Too much animal protein is destructive to the if it is leucine or not which is the problem, The problem is still meat protein. While people are taking the reductionist approach to issue I am taking the traditional approach (of countries of color) and a meat heavy diet was not part of it,

          • I think it might very well have something to do with leucine and very well might be leucine in combination with something else in animal protein that is the culprit. The issues with the reductionist thought is that total effects are attributed to single nutrients where it is likely the nutrient in reaction to other nutrients cause the wider effect. Case in point that it might be leucine in combination with other substances in meat that is the culprit, but that same reaction does not happen or happen as extremely in plant protein. So while it is likely better to warn people about leucine meat consumption, the same conclusion shouldn’t be made for leucine almond consumption.

          • Gayle Delaney

            Hi Aqiyl, If you like OLD wheat grains, have you ever tried Einkorn bread? Einkorn is much older than Kamut and we love the taste made from flour bought online and baked in our Cuisinart bread maker. (no need for expensive bread makers).

          • Hi Gale I haven’t tried Einkorn. I will look into it. I usually stick to spelt, amaranth, quinoa, and, Kamut.

          • Just one more wonderful thing we discovered since going vegan. Your other grains and seeds are delicious too! We do not claim any superior nutrition from Einkorn.

          • Peace and Blessings be with you Gayle.

          • Thea

            Gayle: I’ve heard of Kamut, but not Einkorn. Thanks for the tip!

        • newjumpswing

          Good point. As a vegetarian for more than 4 decades, I think it important to say to people that leucine is necessary for muscle function and development.Leucine is NEVER a bad thing, its the source(animal) and amounts that are taken in as the result of a typical meat/dairy based diet that’s bad.

  • Excellent my brother!

  • Gayle Delaney

    Good News. But what about the autophagy and possible neurogenisis that fasting, or near-fasting popularized by Dr. Michael Mosley’s BBC special and 5:2 diet which we have practiced for about 7 months? Is it worth it? Just how many hours of no or few calories suffice to get enough done in the areas of autophagy and possible? likely? neurogneisis?

    Richard Head MD, a friend of ours in Mill Valley, CA and retired radiologist of tremendous energy, a near-vegan, writes a health blog and tries to provide facts to overcome emotional resistance to same. His blog , chapter 25 ( )
    includes this on fasting:

    A lot of work over many years shows that decreasing the amount of calories ingested (30%)will decrease aging. (See previous discussions). However, it is not proven this works in humans. It is known that excess calories, forming fat, will increase aging and chronic disease. One of the chemicals associated with this antiaging is Reservatrol which causes a number of positive effects. It appears the the starving releases this material. It is also found in certain foods. It appears to offer a number of ways to help our health including blocking the division of some cancer cells. Older people with less calorie intake appear to have less memory loss, then those with more caloric intake.

    Recent studies show that the primary mechanism that decrease calories (and vigorous exercise!) work to trigger off signals to increase autophagy (cell repair). This is an important way the body actually destroys various things that are malfunctioning. Without this cleanup the cells will divide and spread the malfunction so that various diseases and aging occur. It appears a certain amount of physical stress is important to make sure our body is healthy. (see chapter on exercise). The fasting time during sleep is very important to allow these functions to happen.

    Recently there has been emphasis on the benefits of fasting. 50 plus years of research has shown that reducing calories by 30% in animals increases their life span and lowers chance of most disease. It has been shown this is due to shift from cell division to cell repair and maintenace. Many genes are activated by the “stress’ of less calories. These allow many important repairs to occur. The results in many lab animals are available, longer life (40%), less cancer, heart disease etc, more neurons , less hypertension and diabetes. .

    “Fasting causes hunger or stress. In response, the body releases more cholesterol, allowing it to utilize fat as a source of fuel, instead of glucose. This decreases the number of fat cells in the body,” . “This is important because the fewer fat cells a body has, the less likely it will experience insulin resistance, or diabetes.”
    It seems that one major effect of the fast idea (along with the activation of many protective genes) is the lowering of an important chemical in our bodies Insulin like growth Factor, IGF. This is produced by the liver and is released by Growth Hormone. it is active when we are young and growing but is supposed to lower when we age. It promotes division and cell activity and diminishes repair and maintenance. As we age we need more repair and less new cells. A group in South America, dwarfs, have a gene mutation and have low HG and low IGF. They live long lives, have no cancers or chronic diseases. Besides GH high protein in our diets stimulate IGF.

    A vegan diet is associated with a 50% reduction in IGF in the blood. This diet releases a protein that binds the IGF so it cannot be active. The blood from these patients had 8X the ability to stop cancer cell line growth as regular diets.

    Dr. Michael Mosley has become the “poster boy” of fasting. He did a 5:2 fast plan. two , non consecutive days of fast , out of 7. On the fast days he limited himself to 600 calories. Either one meal or two small meals of 300 calories. He limited his protein. On the “regular” days he ate a normal diet of 1600 to 2000 calories. Again, watched the protein amount ( should not have more then 0.4 grams of protein intake per pound of weight). His results after 5 weeks showed 50% lowering of the IGF, lowered insulin from 110 (pre diabetic) to 90 (normal) and lost 15 lbs. His cholesterol lowered. This is only one case but shows the possibilities.

    It takes about 16 hours for the glycogen stores in the liver to deplete. It is probably this that triggers off the many signals to activate our amazing body pharmacy to repair and recycle. I think the fast should allow at least 18 hours or so of no calories to allow this to happen.

    In chapter 32, Richard writes on
    How and why we age …

    • Fascinating, that Michael Mosley.

      I’d like to see Dr. Fuhrman weigh in on his 5:2 plan. Why not water fast those 2 days?

    • Arjan den Hollander.

      Lady you are stressing yourself out over these restriction things.
      Stressing while restricting will cancel each other out if not even worse effects.

      I’m suspecting you are wasting good quality time better spent on the joys of your life. What use is a few extra crippled last months when you could be ice skating right now instead of obcessing over what not to eat?

      Relax, calm down and be merry and you will get your extra years even from that alone! Stop being fat obcessed and live, if not longer.

      If my illnesses tought me anything it is that the quality of life is what is important not so much the duration.

      • Baylen Miller

        I hate to admit, but you are so right. I often obsess and research, when I should be outside riding my bike or playing pranks on friends

  • Steven Christensen

    We need to be careful we don’t narrow our focus too much here.

    Given their relative leucine levels one could easily conclude that it is better to eat an egg or two than to much on a handful of soy nuts to satisfy a protein craving. And soy protein isolate, the prime source of protein in many packaged vegetarian products, appears to be worse than going totally carnivore.

    I think more research is needed before the advantages of leucine restriction are emphasized this strongly.

    • Dr. Greger does not recommend any foods containing soy protein isolate. It raises IGF-1 more than dairy. However, it does not lower IGF-1 binding protein as animal foods tend to do, so one can not say the net effect may be worse than going carnivore.

      PS. You mean omnivore, right? Humans are definitely not obligate carnivores. ;-)

      • Steven Christensen

        I was using “carnivore” as a ridiculous extreme… but you are absolutely correct.

    • Rivka Freeman

      One whole organic pesticide free pasture raised Egg daily is allowed according to to keep blood sugar and everything else in a therapeutic Zone.

      • Devin Wiesner

        I strongly support the benefits of reducing inflammation. However I would encourage you to research some of the basic tenants of the Zone diet. Fish consumption, for instance, is pretty toxic. Please search on NutritionFacts and you will find studies showing that our fish supply is severely polluted with Industrial contaminants:

        • Rivka Freeman

          Oh I searched and yes I agree the fish and anyone who eats them are Fu_kushima_ed. I am doing the Zone Vegan; except that I still like grass fed organic Chalav Yisroel dairy. Dr Sears likes Vegans. He doesn’t hold by eating fish either, he is into molecularly distilled and very purified fish oil capsules. I think vegan sources of omega 3 work really good. The daily minimum requirement to be ok if you don’t consume any other fats except nuts, seeds, avocado, olives, coconut and small amounts of extra virgin olive oil is 4000mg of omega 3 like from 2 tablespoons ground flax seeds.

        • Timar

          The usual kind of fearmongering, concerning all kinds animal products, Dr. Greger often indulges in.

          Epidemiological evidence reigns supreme in this case. There is a clear-cut, positive association between fish consumption and good health.

          You can’t, one the one hand, argue that “nutritionism” is flawed and that you have to regard the whole food (see Collin Campbell’s latest book), and then on the other hand neatly divide fish into omega-3-FA and contaminants, in order to claim that you can get the all the benefits without the purported risks.

          You just can’t know for sure what it is in or about the fish that makes it so healthy. Maybe even the hormetic effects of some contaminants have beneficial health effects? We just don’t know. What we do know beyond any doubt is that regular fish consumption is healthy. Period.

  • Gayle Delaney

    In case my recent post does not make it obvious, I think Dr. Greger and his work are TOPS! The best we have found and we are so very grateful to “our borhter as Aqiyi (bleow) says. What a change he has made in our lives and even his humor and cadences have influenced my public speaking and our conversations on other matters! Thank you,
    Dr. Greger!

  • Anita Turner

    Being a vegan is freeing, I have soo many choices of fruit, veggies, and legumes..and YES all the nuts and seeds I want too..not concerned about watching my weight. I’ve dropped 3 dress sizes since becoming vegan a year ago. oh and my blood pressure is back to normal.

    • Psych MD

      I completely agree with Anita. Vegetarianism is liberating. I find people’s dietary habits interesting. We have various noon-time meetings throughout the month which are catered by a mediterranean restaurant. I always order the veggie plate which is a delicious combo of hummus, tabbouleh,bulgur wheat, turnips, falafel, rolled grape leaves and Greek salad. The psychologist, who BTW, is a lymphoma survivor, always orders chicken kebab which also comes with greens, onions, and assorted bell peppers. He has such an aversion to vegetables that he cannot stand the thought of their touching his meat. In the past he would simply shove them to the side of the plate. After a while even the sight of them became repugnant so now, prior each meal, he meticulously scrapes them into the trash.

      • bob

        As an erstwhile life extensionist and avid reader on health issues and subscriber to health newsletters…I see a “conflict” between those who expouse “squaring the curve” by improving and speeding up life and metabolisim in a more immediate fashion vs those focused slowing things down thru metabolic restriction and reducing protein intake. I tend to eat too many calories…but also have a fairly balanced/varied diet…and take many supplements…including resveratrol/COQ10/PPQ.
        The first approach is that of increasing metabolic activity…the second that of reducing it and directing it towards the eventual metabolic “wall of death”? Is it possible to do both?

      • Timar

        This is a story about the bad dietary habits of your colleague, not about the benefits of being a vegetarian. You don’t need to be a vegetarian to enjoy your vegetables. You don’t even need to be a vegetarian to eat a predominantly plant-based diet…

    • Timar

      Following this logic, every kind of dietary restriction is liberating.

      I’m a flexitarian and I am not concerned at all about weight or blood pressure, too. I don’t need to be “liberated” from my home-made yogurt, parmesan or feta cheese, but rather enjoy the full bounty of Nature and traditional foods. If you are accustomed to a good dietary habits (whole foods, mostly plants, not too much) there is no need for any liberation, as you are consuming all types of food in healthy ratios, just like the traditional “Blue Zone” cultures did for hundreds of years. None of those traditional diets is/was “vegan”, but they all are “plant-based”, deriving most of their calories from plant foods.

      • hillaryrettig

        Agree with your emphasis on whole foods, Timar, but believe me it’s also liberating to know that one’s meals are not contributing to the torment of other beings, not to mention climate change and other environmental degradation, and abuse of human labor.

        • Timar

          Well, I’m with you: eat as much organic, locally grown and produced foods as you can afford. And buy fair trade when it comes to coffee, tea, cocoa or anything imported from developing countries.

          Of course if you have a moral problem with killing animals for food you should follow a vegetarian or vegan diet. I certainly haven’t, as long as the animals are treated and kept well, according to their species needs (i.e. not confining them to a feedlot).

          • Jim Felder

            The difficulty is that animal agriculture has more impact on climate change (18%-51%) than all the cars, buses, trucks, trains, ships and airplanes combined (12%).

            The 18% estimate is from the UN report “Livestocks Long Shadow” It was prepared by the FAO, which is the UN agency in charge of promoting among other things the production of animal foods around the world.

            The 51% estimate comes from two climatologist who work for the World Bank They feel the FAO didn’t take all climate impacts into account, such as the loss of carbon sink capability of forests cut down in order to grow more feed.

            Whether you agree with all the conclusions in the World Bank report of not, you can see that livestock is the single largest driver of climate change.

            Pastured meat, dairy and eggs isn’t the answer either. The amount of pasture required is such that we would require every square foot of *all* of North America, Central America and the Northern third of South America just to meet current American demands for these products. (

            Now I know that you have cut back a lot and if everybody did that we might be able to all eat a bit of pastured animal foods without having to turn our entire landmass into pasture. Still if we didn’t eat any, more land could be returned to natural conditions, which are generally better carbon sinks than open grasslands. And we need every bit of help pulling carbon out of the atmosphere that we can get.

          • Thea

            Jim: Thank you for explaining the differences between the 18% number and the 51% number. I have seen both of those numbers before and wondered where the discrepancy came in. Thanks! Great post.

  • I would like to echo Gayle here. Listening to all of your videos has been invaluable in developing a clear communication style for the many curious parties that have questions when confronted with WFPB as an option. My wife and I sell WFPB foods at farmers markets and it means so much to have your videos and blogs to refer to with the frequency we are challenged.

  • Martin Miller Poynter

    I, too, would love to see some videos about fasting generally, water fasting, juice fasting, and 5:2 fasting. Would love to know if there have been studies about the effects of fasting.

    • Baylen Miller

      I know right! I have posted on videos requesting it but idk how to make it known to him :(

  • Eileen

    I am so thankful for this information. I have been using food as medicine for almost 3 years after a diagnosis of breast cancer. I was first told it was fine to eat a lot of fish. We are eating mostly plant-based now, thanks to Dr. Greger and Dr. Fuhrman. I can’t thank you enough for this service that you provide to us. I also can’t get enough of your sublime delivery and fabulous voice!

  • Merio

    I love the photo of the mini mini mini burger… is that a candy ? :-)

    • Tommasina

      I think it is! The images are from Flickr users so who knows what’s in them. :)

      • Merio

        Thanks for the answer !

        BTW your avatar photo is really nice !

  • Psych MD

    69% of kcal from sweet potatoes? Wow! As soon as I read that I paused the video and popped one into the microwave.

    • Toxins

      They ate the Okinawan purple sweet potatoes, which are extremely tasty. Its important to note the Okinawans in the prime of their days had the most centenarians per capita.

  • Adrienne Lee

    Thumbs up, thanks for your commitment to truthful education.

  • Gregory

    Advertists consume a lot of soy which is high in Leucine but yet live longer than any other studied group. There must be more to it that we are not seeing.

    • Kal

      Soy protein is not high in leucine, its about even with bean protein, rice protein, meat protein, and even kale protein. I’m at a loss as to how the good doctor blew the interpretation of the data so bad this time, except to think that everyone has bad days now and then. The possible bad implications of excess leucine would be relevant to excess protein intake, not just animal protein. The graph that showed the difference in leucine content was based on 100 gram servings. As the leucine content of the food item protein fractions was effectively equal across the board, all the graph showed was relative protein content. Granted, with meat and beans its easier to consume too much protein, but that doesnt make either bad, it just makes wisdom and self control that much better.

      • Timar

        I couldn’t agree more.

  • Jim

    why do women in all societies live longer than men?

    • Hormones and occupational risk.

    • guest2

      They’re less likely to suffer from hemochromatosis because of their monthly menses. This puts them in good stead for old age. Men however can get the same protection be avoiding the heme iron found in animal products or by donating blood.

    • Darryl

      Around 73% of the difference is due to lifestyle choices:

      Life expectancy Men Women Difference
      Californians 73.9 79.5 5.6
      Adventists 81.2 83.9 2.7
      Vegetarian Adventists 83.3 85.7 2.4
      Healthy* Adventists 87.0 88.5 1.5

      * never-smoking, vegetarian, exercise ≥ 3 times weekly, eat nuts ≥ 4 times weekly, BMI < 25.90 (males) or <25.20 (females).

  • baby_grand

    Great video, ground-breaking in fact. I can skip soy except some very occasional edamame, which is soon tiring, like everything else plant-based that I consume. My current diet is mostly plant-based, no dairy, little if any meat, and I add juiced beets, kale, lemons, carrots, celery, parsely to a blended salad with spinach and romaine, RAW Life protein powder and ground flax seed daily. This is a high nitric oxide dietary formula. Over age 40 we need more beets and spinach to supplement for loss of ability to convert arginine to nitric oxide.

  • Aaron Kester

    Is there a list of Leucine relative to a standardized protein level? For example mg/10 grams of protein from beef, soy, milk, beans, etc. As other have mentioned, mg/100kg serving can be misleading because the total amount of protein is different between foods in this measurement.

    • Darryl

      Roll your own. Dr. William Harris converted the USDA food database to an Excel spreadsheet. Its not at all difficult to enter a “=cell/cell” formula as an entry and copy it through a column to get g leucine per g protein, leucine per kcal, or my favorites like leucine/lysine or methionine/lysine. For those who don’t have a copy of Excel, there are fine (in some respects, superior) open source software like OpenOffice which works fine.

      • Lawrence

        Darryl, great suggestion. I have been using Dr. Harris’s spreadsheet for some time now. Dr. Harris is a big proponent of sorting foods by nutrient/calorie ratio, and to summarize: animal foods and soy isolates have about 2 grams leucine per 100 calories while beans and tofu have about half a gram leucine per 100 calories, which is the same proportions Dr. Greger shows in this video.

      • Aaron Kester

        I took your advice and I quickly did make a spreadsheet that I can share with everyone. I choose some common foods for contrast and added a cell of the % of the protein content derived from Leucine. The results surprised me. Of course total protein content is also very important as that determines the overall “leucine load” but just looking at the percent derived from leucine is interesting as well.

        • JacquieRN

          Thanks Aaron. Appreciate the post.

        • Thea

          Aaron: It took me a while to get to your post, but I’m glad I took a moment to check it out. Your spreadsheet is great! Thanks for sharing!

      • JacquieRN

        Nice, thanks Darryl

  • DGH

    Keep eating plant foods. Today at lunch they served cookies, various sandwiches (including so-called vegetarian ones containing egg salad and feta cheese) and I just ate three plates of fruits and veggies (and brought my own vegan sandwich). I looked around the room and saw several people manifesting early obesity and advanced aging. It was interesting to correlate what people ate with how they looked. I will continue to eat as much plant-based food as I want until I am full and not worry too much about macronutrient distributions or total caloric intake, relying on my own sense of satiety and intrinsically filling fiber-dense plant foods to get me through. Caloric restriction is great if you are overweight but if not, then you just end up tired and osteopenic and too fagged to exercise.

    • Darryl

      I looked around the room and saw several people manifesting early obesity and advanced aging. It was interesting to correlate what people ate with how they looked.

      Every single time I shop for groceries.

      • Timar

        Me too. But from my observations it seems hardly related to the amount of animal products in the shopping cart, but rather to the amount of processed, refined and manufactured food (or rather “edible foodlike substances, as Michael Pollan put it).

        • Veganrunner

          Hi Timar,
          I see you enjoy Michael Pollan’s books. I too read them as them were published and practiced “mostly plants” idea. Then I read two books written by vegan athletes who talked about recovering faster after long runs. I had already been enjoying Dr Greger’s website so the books and these videos made the switch easy. I didn’t eat processed foods before my switch. Actually I can’t remember a time when I did. Also primarily organic since it was a available.

          But here is the weird part. Since going vegan I am taking less thyroid medication every time I go in to have it checked. I have been on this medication for 18 years with no fluctuations before.

          And before you say

          • Thea

            Veganrunner: This is a great example of how the concept of “moderation” fails us. Thanks for the post.

          • Veganrunner

            I can’t agree more. Even after 2 years of giving up the meat/fish my thyroid med is still going down. So strange. I wonder if anyone else has had a similar response?

          • Timar

            No, it isn’t. It is a great example of how we are all individuals, with our own, individual health concerns and dietary requirements ;)

          • Timar

            It’s great that you have found a diet that works for you and that helps to keep your thyroid problems in check! I’m doing fine on my flexitarian diet too, with excellent biomarkers and no health issues.

            However, I have seen a lot of reports similar to yours, but many of them (pretty much half, I guess) are just the other way around: people who have followed a plant-based diet for years experienced health benefits when they included some animal products.

            I guess they are all right. There are a myriad of reasons why people do better eating or avoding certain foods. For some people, animal protein may contribute to low-level inflamation, for other people it may have beneficial effects. Some people get all their vitamin A from plant foods, while a few people lack the enzyme that splits beta-carotene into retinol and need preformed vitamin A to feel healthy.

            There’s a vast biochemical individuality related to nutrition, which we only have begun to understand on a genetic level (sometimes refered to as nutrigenetics). This is why there is no optimum diet for everyone beyond the basic rules Micheal Pollan described so aptly. We all need to start from there and figure out for ourselves.

  • Lawrence

    “Autophagy: It’s what’s for dinner.”
    Great set of videos, Dr. G. Your ability to present complex information in a digestible format is second to none, and your choice of topics continues to raise my game. As an added bonus, you provide the source material which-in this case-is enough for PBS to start a new series called, “This Old Mouse.”

  • Thank you Dr Greger. Your work helps to keep my husband and I on the WFPB diet. And we try to spread the word despite the tomato effect, the nutritional advice of mainstream media and the latest fad diet.

  • Broccoli

    Japanese people also have good sexuality and good soft smooth skin.

    • Timar

      You have slept with many of them, don’t you? ;)

  • clarkbennett

    A Plant based diet is great! Large portions, nutritionally dense and lower in calories than a meat based diet. If I ate as much meat as i do veggies I’d be huge.

  • McMullans
  • Peter

    Question to Dr Greger: Soy products like “fake meats” containing Isolated soy protein is a no go then? I’ve read that the isolated soy protein actually raises IGF1-levels more than cow’s milk. (Starch Solution by Dr John Mcdougall)

  • eyboikos

    But leucine is found in soy and other plant products..

  • Teresa

    watch your videos incessantly … (fighting cancer) … watching this one, overcome with gratitude … Thank you SO much for your work… what an amazing, incredible gift… I NEED the science to have the discipline to choose what is healthy.

  • Catherine

    I am all in on the plant based diet. But the other side of it is the side effect of a diet high in oxalates. Oxalates come in the darker vegetables, beans and nuts which I have been living on for several years now. I developed a very painful condition called vulvadynia. I am now taking calcium citrate and weaning myself from those wonderfully “healthy” foods including whole wheat and gluten and soy and am experiencing tremendous relief. What’s a health conscious eater to do?

  • Sebastian Tristan

    Boy am I confused… O.K. We’ve had some videos regarding adequate protein intake. The scientific mantra is that the best ratio is 0.8-1.2 grams of protein per kg of optimal body weight. Nevertheless, the Doc mentioned a study that criticized this concept, saying that we should maybe strive more for 1.2 gr/kg. Do we scrap this? Because at 10% protein, I would never reach the 90 gr of protein per day. I need answers because A) for years I have tried to pack as much protein as I can in my meals, which can be difficult if you consume a vegan diet; B) I am very active physically.

  • Tobias Brown

    I started using Cronometer to track my plant-based nutritional profile… My fiber intake is almost double the minimum. No problem there. However, my total protein intake is 215% over the RDV. But the lowest component is methionine at 105%. So, how can I lower the total without bringing this one lower as well and breaking below the minimum?

  • Ted

    The table shows Okinawans eat 69% of their calories from sweet potatoes and only 3% from vegetables. Perhaps other routes than leafy greens to get to the same longevity.

    • Toxins

      I consider sweet potatoes part vegetable, especially since Okinawan sweet potatoes are a deep purple color. The antioxidant content of sweet potatoes are very high, as Dr. greger will discuss in a near future video.

    • Tom Goff

      A “vegetable” is a plant or part of a plant used as food. So, literally, fruits nuts, seeds, tubers are all vegetables because they are parts of a plant. Unfortunately, lazy colloquial usage tens to obscure the correct meaning of the word.

  • Colleen

    I love your videos! Amazing job linking research studies!!! (:

  • Technus

    Good to know! Of course nobody else is going to admit that limiting protein intake is just as effective for longevity as calorie restriction. Some would just rather starve. As a vegan, I’m never starving.. always pigging out and wondering how I manage to keep the weight off :-)

  • Lawrence

    Dear Doctor have you seen this article?

  • Brenda Ross

    Gotta say that most places, when you read the comments, they are riddled with disrespectful and ill informed people. This is the first time I have seen constructive discussion taking place. Brilliant.

    • Thea

      Brenda: Thank you very much for this nice feedback. We don’t always succeed, but we try very hard at NutrtionFacts to make the comments section a pleasant and helpful community for everyone. Thanks for noticing.

  • BenzoSt

    In looking for ways to increase my longevity, I have been made aware of the potential benefit of caloric restriction and/or intermittent fasting. BCAA supplements (typically a mixture of leucine, isoleucine, and valine) are supposed to be helpful for retaining muscle while fasting.

    Of all the poking around the internet to learn about BCAA benefits/risks, the most scientifically-referenced-looking piece of seconday literature was at:

    Take note of the paragraph near the end with the heading “#10: BCAAs Correlate With Longevity and Are Therapeutic”.

    Side note: I can’t remember my source, but I was informed that Okinawans consume pork fairly regularly. Coincidentally I don’t enjoy eating pork but do enjoy eating the other Okinawan staple food – sweet potato.

    • Thea

      re: “I was informed that Okinawans consume pork fairly regularly.” I suppose that could be technically true if frequency is an issue and is well defined, but it is very misleading. My understanding is that historically, traditional Okinwan’s ate 4% animal products. This includes all dairy, fish and other meats. Even if pork were part of that 4%, it would not be a significant part of their diet.

      Sweet potatoes, on the other hand, was something like 70% (if I remember correctly). So, good thing you like those sweet potatos!

      • Toxins

        Speaking of Okinawan sweet potatoes, every November they are in most major grocery stores for a short period of time, so save the date and stock up when you can!

        • Thea

          Great tip! Thanks. :-)

  • William Dwyer

    Leucine and Weight Loss

    Researchers have looked at the response of adipocytes to leucine deprivation (taking leucine from the diet). Much of the following is based on animal research, as it is difficult to justify refusing human subjects an essential micronutrient. When mice were provided with a leucine-depleted diet, fat loss was greater. Lipolysis, the release of stored fat, was increased; lipogenic enzymes, including fatty acid synthase, were reduced; and uncoupling protein was increased in brown fat, which results in burning more fat for heat production.How much weight loss was experienced by the leucine-deprived mice, and how did it occur? The leucine deprived mice lost about 15 percent body mass, related in part to a near equivalent reduction in daily calorie intake (15 percent). However, an increase in energy expenditure was also present; typically, when energy intake goes down, so does energy expenditure, as the body tries to conserve in an environment of limited resources (food).

    A separate group of mice that was fed an equal number of calories, containing a normal leucine content, lost only 5 percent of bodyweight. Of the weight lost, the leucine-deprived mice lost a significant amount from the abdominal fat depot, roughly 40 percent; the leucine-fed mice fed the same number of calories did not lose a significant amount of abdominal fat. Total body fat was similarly affected.

    Markers of metabolism supported the hypothesis that energy expenditure was increased in leucine deprived mice. Serum (blood) norepinephrine and T3 were elevated in the leucine-deprived group; body temperature was elevated; and brown fat was activated, turning fat calories into heat as opposed to energy; the leucine-deprived mice managed to burn more calories, specifically fat for calories, without any increase in physical activity.

    The net result was a marked 42 percent decrease in white adipose (the storage form of fat) volume.This was accomplished by increasing the activity of hormones involved in breaking down the stored fat, and burning much of that fat in the adipocyte. A 200 percent increase in PPAR-alpha was recorded, along with increases in the fat-burning enzymes stimulated by PPAR-alpha protein. As more fat was being lost, less was being made. One enzyme important to storing fat, called fatty acid synthase, was suppressed over 30 percent in white, adipose tissue. A prior study by the same authors showed a similar effect on suppressing fatty acid synthase in the liver of leucine-deprived mice.

    Of course, bodybuilders are scoffing at the notion, regardless of fat loss, because everyone knows depriving the body of the essential branched-chain amino acid leucine would lead to catastrophic losses in lean mass… right?

    Actually, the leucine-deprived mice showed no difference in lean mass, from either the control mice or those that were restricted to the same number of (reduced) calories consumed by the leucine-deprived mice. The control mice are normal mice, eating as much as they will; the pair-fed mice are normal mice eating a normal diet, but only as much as the leucine-deprived mice chose to eat; the leucine deprived mice ate as much as they wanted, but they chose to eat 15 percent less than the control mice, (thus, the pair-fed also ate 15 percent less than control, but it was a diet that contained a normal amount of leucine).

    Pair-fed mice lost only 5 percent of bodyweight, and their lean mass did not change appreciably; leucine deprived mice lost 15 percent of body-weight, and their lean mass was the same as the control mice, and unchanged.There were no strength or endurance challenges, but when one considers that the mice lost 50 percent of abdominal fat, 15 percent of bodyweight, and had no loss of lean mass, that is incredible.

  • Chris Hartley

    I just had a look at my 100% vegan protein powder and it’s 7.3% Leucine by weight – a bit of a shock

  • Arjan den Hollander.

    Low IGF-1, lots of sweet potatoes, and greens. Oompa loompas!!!

  • Michael

    Dr. Greger,

    It seems that both signaling muscle protein synthesis (MPS) and aging prematurely (as discussed in this and previous video) involve the leucine/mTOR connection. Do you think, or is there research, that long life and building muscle mass are fundamentally opposed goals based on how our body is designed? Also, do you think, or is there research, that the mTOR theory of aging and leucine acting as a trigger could be meat/animal-protein specific? In other words, could eating leucine-rich plant foods in order to signal MPS still provide longevity benefits as well as muscle-building benefits? Kind of similar to the whole nitrate/nitrite conundrum where plant-sourced nitrates (from beets and arugula) get metabolized in the stomach and re-sent to the mouth where, instead of becoming carcinogenic nitrosamines (as is what happens when you consume nitrates from meat), they become NO and increase our oxygen efficiency. This seems plausible to me since you’ve praised pumpkins seeds (which are relatively high in leucine) in some past videos: ( specifically the mineral content and serotonin boosting effect.

    Research papers describing MPS and leucine signaling:

    • Joseph Gonzales R.D.

      Super important questions especially for body builders who may want to follow a more plant-based diet. I think you are onto something. Plant-based diets have been shown to work successfully in athletes, but over-consuming protein and working your muscles day in day out to me seems like there could be a downside. I know many plant-based athletes who refrain from large supplements and stick to whole foods. Let me research this a bit more and read your studies. Forgive my delay I will answer you as best as possible. Do you want my links to plant-based athletic research? Thanks, Michael

      • Michael

        Thanks for the reply, Joseph!

        I would love to review what research you can share. From what I have read, relating to popular plant-based athletes, it seems the main focus has been on endurance athletes rather than athletes concerned with hypertrophy. Of the anecdotal plant-based bodybuilders stories that I’ve read, they are relatively recent converts to a PB diet (i.e. they were winning athletes with large muscles before converting, and have been able to retain their mass and increase their recovery once switching diets). My question is more about building muscle mass while on a PB diet which is something that I haven’t found much research on.

        Also as I stated above, I am very fascinated by the possibility that leucine/mTOR could be an analogue to the nitrate/nitrosamine/NO connection — that plants cause benefit where meat causes harm.

  • Mr.Bill

    Dr Greger,

    I love your videos. However, I do not believe that you always present the facts as straight forward and objectively as they could be. From your video, one would believe that chicken has more leucine than kale. However, the amount of leucine per gram of protein from chicken is very close to the amount of leucine per gram of protein in kale. Yes, there is more protein in 3 oz of chicken than 3 oz of kale, but per gram of protein. leucine content is very similar.

    So the objective seems more to limit total protein consumption rather than from what the protein is derived. Obviously, avoiding animal products is a great way to reduce total protein consumption, but I believe most people from this video would believe that 60 grams of protein from animal products has substantaily more leucine than 60 grams of protein from navy beans. According to nutrition facts and analysis, 60 grams of chicken protein has 4200 mg of leucine and 60 grams of protein from navy beans has 5100 mg of leucine. Clearly, that is different than what anyone watching this video would believe.

    My concern is that I wonder how many other video analyses also have such bias toward veganism.

    • Jim Felder

      The difference is that with a diet centered around animal products, it is difficult to get a day’s worth of calories without getting excess protein. Can you devise a diet where a substantial percentage of total calories comes from animal products that A) has the same number of grams of protein and B) has the same number of calories as a WFPB without resorting to refined sugars and oils to up the calories without any additional protein.

      The frequent knock on WFPB diets is that they “lack” protein. And relative to a meat-centric diet, it does. But that also means that eating a WFPB diet it is relatively easy to get enough calories to maintain weight while still keeping protein consumption to that required for body maintenance (~5-10% of total calories). Not covered in this video, but I would be willing to bet that an increase in TOR signalling starts at the level of protein required for maintenance. It would be very interesting to know if luciene in protein up to the maintenance level has any effect on TOR.

      But your point is well taken. A lot of people eating a WFPB worry about getting “enough” protein, and so devote particular attention to eating plant foods particularly high in protein, like beans, or even going to the extreme of eating isolated protein supplements like pea protein to make sure that they “get enough”. I know that I did at least initially. But I don’t any more because I demonstrated to myself that a given amount of just about any whole plant food, save fruits, supplies the same or higher percentage of daily protein requirements than that same amount contributes towards daily calorie requirements. The same also applies to each of the essential amino acids as to protein overall. The bottom line is that if you eat enough calories, protein just takes care of itself. No need to make any special effort what so ever. And with the information in this video, it might be wise to actually do a bit of the reverse and focus a little extra on the lower protein foods like rice, wheat, potatoes and a little less on high protein foods like legumes. And we should eat greens because they are just jammed full of nutrients rather than the fact that 40-50% of the calories (even though the number of calories is very modest) come from protein.

      • mr.bill

        I agree with what you said. I just wanted to point out that for a fixed amount of grams of protein either from plants or animal, leucine content is about the same so the only way to really limit leucine is to limit protein. However, methionine levels are much lower in plant based protein rather animal based protein so a WFPB is the only way to go.

      • Tom Goff

        Thanks. These are useful observations. They might also explain why plant based low carb diets are not associated with lower all-cause or cardiovascular mortality (although animal based low carb diets are associated with higher all-cause and cardiovascular mortality).

  • Tom Goff

    There is a very interesting video on this broad topic below (it lasts about 40 minutes). It seems to indicate that methionine restriction may account for many of the benefits of calorie/protein restriction.

    • Thea

      Tom: Great lecture. Thanks for the link!

  • Caroline

    Your article states that, “To reach the leucine intake provided by dairy or meat, we’d have to eat nine pounds of cabbage—about four big heads—or 100 apples. These calculations exemplify the extreme differences in leucine amounts provided by a conventional diet in comparison to a plant-based diet.”

    Why not present a more protein-equivalent comparison like beans, rather than an extreme example of vegetarian foods that contain very little protein? This type of apples-to-oranges comparison leads me to question the objectivity of your reporting.

    • Joseph Gonzales R.D.

      Hi Caroline. There is a lot of discussion about leucine content in plant foods on the latests blog today about TOR. See if that thread helps answer your questions? I’m to happy to help answer any additional questions you have and agree that maybe comparing beans and plant sources that tend to be high in leucine is more appropriate. Thanks for your comment.

  • SpikesDad11

    Great video and comments but I thought that caloric restriction as a mechanism for increasing longevity in primates has been discredited in recent studies such as . I don’t think this negates Dr. Greger’s points/conclusions in this video but I have noticed that he asserts that “the benefits of caloric restriction on health and aging has been clearly demonstrated” (i’m assuming he means in humans) in several videos and blog posts including today’s (15June 2015) post “Living Longer by Reducing Leucine Intake”. Again, I’m not debating the good doctor’s conclusions but just wondering why he continues to make assertions that i thought were essentially disproven. Also wondering why this point has not been brought up in any of the numerous comments for this video. Please enlighten me :).

    • Tom Goff

      A later (2014) study in primates confirmed the benefits of calorie restriction. It suggested that, in the 2012 study you refer to, the control group of monkeys was also effectively undergoing calorie restriction which explains why there was no benefit found in that study.
      “Here we show that CR significantly improves age-related and all-cause survival in monkeys on a long-term ~30% restricted diet since young adulthood. These data contrast with observations in the 2012 NIA intramural study report, where a difference in survival was not detected between control-fed and CR monkeys. A comparison of body weight of control animals from both studies with each other, and against data collected in a multi-centred relational database of primate ageing, suggests that the NIA control monkeys were effectively undergoing CR. Our data indicate that the benefits of CR on ageing are conserved in primates.”

  • Sandy

    I was watching this video while my 11 year old daughter is sitting next engaged in something else and seemingly not paying listening. Until she responds to the question, “So where is luecine found?” Her response, “McDonald’s.” :) I think her passive nurtion facts education is having a positive effect. I’ll continue to keep the volume turned up.

    • Sandy

      oops on the typos… “11 year old daughter is sitting NEXT to me engaged…” and ” ..seemingly not listening.”

    • Thea

      Sandy: You made my day with your story. Tickled my funny bone. :-) Yeah you! And yeah your daughter too.

  • john tiffany

    Paul Jaminet writes “As I mentioned yesterday, I have a Google
    Alert for centenarian stories and have been reading about them for
    some time. One thing I’ve found is that most centenarians don’t
    seem to think very much about their diets (which protects them from
    the food pyramid!), but supercentenarians tend to be very picky about
    what they eat. Supercentenarian diets come in two basic
    1) Calorie-restriction and
    intermittent fasting.
    2) High (saturated and
    monounsaturated) fat low-carb diets.”
    Is that last bit about the “two flavors” true? I believe you
    recommend strongly against saturated fat and do not say we should
    restrict calories, right? Your video says it makes more sense to restrict proteins, especially animal proteins containing high levels of leucine. Therefore Jaminet must be mistaken, isn’t
    he? What about intermittent fasting—doesn’t it lead to autophagy,
    which can be a good thing? Also can you comment generally about supercentenarians please?
    –john tiffany
    Information From:

  • CommanderBill3

    The problem I have with this video is Dr. Greger fails to mention that Leucine is an essential amino acid, meaning that the human body cannot synthesize it, and it therefore must be ingested to live. Moreover the highest quanity of Leucine per gram of food source is soy beans, followed by beef, peanuts, fish, wheat germ, almonds and chicken.
    It seems to me limiting your Leucine levels would be dangerous and difficult.

    • Thea

      CommanderBill3: The following page has a nice bar graph showing the 1) essential amino acids, 2) how much we need of each acid, 3) how much we get from common plant foods. (Scroll down a bit)

      It’s not a matter of getting the highest quantity of any particular amino acid. The issue is how to cover our dietary needs. It looks to me like common plant foods (even ice berg lettuce!) cover our essential protein needs just fine.

      • CommanderBill3

        I think your missing my point. The video suggested that we could live a longer life by limiting our dietary Leucine by reduction or elimination of eating meat. What the video failed to mention is Leucine is essential and it is in a great deal of foods besides meats. It would be very difficult to limit it’s consumption. Moreover you’ll probably find some one that will try to eliminate for their diet in its entirity with a fatal result.

        • Thea

          CommanderBill3: Thank you for your clarification. I feel I had addressed your points, but your reply makes it clear that I need to be more direct with my wording.

          re: “Moreover you’ll probably find some one that will try to eliminate for their diet in its entirity with a fatal result.” Please review the link I provided above. Repeated here for your convenience:
          The bar graph in the middle of the page makes it clear that it would be impossible to eliminate leucine for anyone eating the diet recommended on this site. They couldn’t do it even if they tried. Your concern is not justified.

          re: “What the video failed to mention is Leucine is essential…” That’s because the point of the video is to limit foods that have excessive amounts of leucine, not to eliminate leucine.

          re: “…and it is in a great deal of foods besides meats.” As mentioned above, leucine isn’t just in “a great deal of foods besides meats”. To my knowledge, leucine is in all whole foods besides meat. And as you point out, it is very good that all whole plant foods have some leucine in them. We just don’t want too much leucine. This point is getting at the concept: “the dose makes the poison.”

          The video is not telling anyone to eliminate leucine. In fact, to my knowledge, that’s impossible on a whole plant food based diet. So, there’s no need to explain that leucine is essential or worry that people will cut out leucine from their diet. Instead, people need to know which foods in general have a whole lot of leucine compared to other foods so that healthier food choices can be made. Following a general practice of choosing foods lower in leucine is how someone can end up with the healthy amounts of leucine.

          From the video: “…just cutting down on leucine may be nearly as effective as cutting down on all protein. So where is leucine found? Predominantly animal foods: eggs, dairy, and meat, including chicken and fish, whereas plant foods have much less: fruits, vegetables, grains, and beans.” Dr. Greger is giving us simple rules of thumb to follow in order to get the right amount of leucine in the end. The video is not telling anyone to precisely measure leucine or worry about eating a few almonds now and then. But if your diet contains lots of meat, dairy and eggs, then you may have a problem…

          I hope this reply is more clear.

  • Diane Alizia

    Are there any studies on fasting? This seems to be a fad now, for ageing and weight loss. What’s more effective–fasting for 3-5 days once a month, 2 days a week, or 16 hours a day. It’s struck that fasting may be a factor as one very strong element of the traditional Cretan diet, albeit never mentioned, is the Orthodox fast which was still a very strong element when Ancel Keys conducted his study and is also very strong among older Ikarians whose longevity has been referenced quite a bit recently.

  • Miroslav Kovar

    I heard about a study finding that elderly people consuming above average amounts of protein showed the least amount of cognitive decline. Does anyone have a reference for the study?

  • Hendrik

    I’m not sure that leucine’s effect on mTOR is the whole story. Glucose is also an upregulator for mTOR, so this could lead to accelerated aging. See the link

  • BenzoSt

    Although leucine does indeed seem to activate TOR, it along with the other branched-chain amino acids isoleucine and valine seem to have some life extending benefits such as activating sirtuins, encouraging mitochondrial replication, and bolstering our internal antioxidant systems as detailed in the following article:

    Branched-chain amino acids, mitochondrial biogenesis, and healthspan: an evolutionary perspective.

    I spent a few hours reading and highlighting this article. At this time, I think leucine is fine and perhaps even desirable. According to the American College of Sports Medicine position stand on nutrition, muscle protein synthesis is improved after strength training by consuming meals containing something like 3-4g of leucine every 3-5 hours.

    Right now, the amino acid I try to limit is methionine because it is substrate for overproduction of homocysteine, which is in turn a risk factor for heart disease.

  • Hendrik

    Leucine also competes with tryptophan in its transport across the blood-brain barrier hence can lead to low serotonin in the brain, see the links at

  • Inches

    I just checked the Bragg liquid animos I use as an alternative to soy sauce and it says it has both leucine and methionine animos. Do plant based (soy) sources of these amino acids have the same effect as animal product sources?

  • Chanjw

    I think I understand the strategy of restricting leucine to avoid TOR, but if I’m wanting to maximize the benefits of autophagy, is there some benefit to be gained from skipping breakfast and maybe lunch and condense my plant based meal(s) to later in the day? I’ve tried it a few times and sort of like how it feels to have an empty stomach. It seems a little easier for me to skip meals than to eat lightly. BTW – even though n=1 is a flaw, have you seen Hershel Walker lately? Life long 1 meal a day guy in his mid fifties looking like his mid thirties.
    PS – I guess everyone saw Nobel Prize awarded recently for work on autophagy.

    • Hi Chanjw,

      I am a volunteer NF moderator and am happy to help. Intermittent fasting does decrease IGF-1 and has been shown to slow down the aging process and reduce some cancer risks Most intermittment fasting benefits are seen from fasting 16-18 hrs per day. Of course, it is always advised to talk to your healthcare practitioner first before long periods of fasting in order to prevent any drops in blood sugar that may be problematic. I hope this helps!