Have you ever wondered if there’s a natural way to lower your high blood pressure, guard against Alzheimer's, lose weight, and feel better? Well as it turns out there is. Michael Greger, M.D. FACLM, founder of NutritionFacts.org, and author of the instant New York Times bestseller “How Not to Die” celebrates evidence-based nutrition to add years to our life and life to our years.

How Much is Enough Protein?

What is the best kind of protein, and how much should we be eating? 

This episode features audio from The Great Protein Fiasco, Which Type of Protein is Better for Our Kidneys?, and Animal Protein Compared to Cigarette Smoking.


Welcome to Nutrition Facts. I’m your host, Dr. Michael Greger, and I’m here to ask you: What is the most important decision you’ll make today? Is it how you’ll get to work, who you’ll set up a meeting with, what friend you’ll call for lunch? Well, as it turns out, probably the most important decision you’ll make today is what to eat. What we eat on a day-to-day basis is the number one determinant of our health and longevity—literally. Most premature deaths in the United States are preventable and related to nutrition. So, we’re going to explore some smart nutrition choices based, naturally, on facts. Here, we refer to the science, the research, the available data published in the peer-reviewed medical literature right now. That’s why I wrote my book, “How Not to Die”, and why I created my nonprofit site NutritionFacts.org and, now, this podcast.

Today, we’ll look into the science on the right kinds and amounts of protein in our diets. As pointed out by the Chair of Harvard’s Nutrition Department, plant protein is preferable to animal protein because food is a package deal. Unlike protein from animal sources, protein from plants has been associated with lower rates of chronic disease.

But, in the 1950’s, the field of nutrition got human protein requirements spectacularly wrong, leading to a massive recalculation. Here’s the story.

There has been a history of enthusiasm for protein in the nutrition world. A century ago, the protein requirements were more than twice what we know them to be today. This enthusiasm peaked in the 1950s, with the United Nations identifying protein deficiency as a serious widespread global problem. There was a protein gap that needed to be filled. This was certainly convenient for the U.S. dairy industry, who could dump their postwar surplus of dried milk onto the third world, rather than having to just bury it. But, this led to the great protein fiasco. There was a disease of malnutrition, called kwashiorkor, that was assumed to be caused by protein deficiency, famously discovered by Dr. Cicely Williams, who spent the latter half of her life debunking the very condition that she first described.

Turns out there’s no real evidence of dietary protein deficiency. The actual cause of kwashiorkor remains obscure, but fecal transplant studies suggest changes in gut flora may be a causal factor. How could the field of nutrition have gotten it so spectacularly wrong? A famous editorial about the profession started with these words: “The dispassionate objectivity of scientists is a myth. No scientist is simply involved in the single-minded pursuit of truth, he or she is also engaged in the passionate pursuit of research grants and professional success. Nutritionists may wish to attack malnutrition, but they also wish to earn their living in ways they find congenial.” This inevitably encourages researchers to “make a case” for the importance of their own portion of the field, and “their nutrient,” which was protein.

Science eventually prevailed, though, and there was massive recalculation of human protein requirements in the 1970s, which “at the stroke of a pen” closed the so-called “protein gap,” and destroyed the theory of this pandemic of “protein malnutrition.” Infant protein requirements went from a recommended 13% of daily calories, down to 10%, then 7%, and then down to 5%; however, to this day, there are still those obsessing about protein. Those promoting Paleolithic diets, for example, try to make the case for protein from an evolutionary perspective.

Okay, so let’s ask the question: What is the perfect food for human beings, the food that was fine-tuned just for us over millions of years to have the perfect amount of protein? Human breast milk. If high-quality protein was the “nutrient among nutrients,” helping us build our big brains over the last few million years, one would expect that importance to be resoundingly reflected in the composition of human breast milk—especially since infancy is the time of our most rapid growth.

But this is patently not the case. Human breast milk is one the lowest-protein milks in the mammalian world. In fact, it may have the lowest protein concentration of any animal in the world—less than 1% protein by weight. This is one of the reasons why feeding straight cow’s milk to babies can be so dangerous. The protein content in human milk is described as extremely low, but it’s not low at all, it’s right where it needs to be. That’s the natural, normal level for the human species fine-tuned over millions of years.

Adults require no more than 0.8 or 0.9 grams of protein per healthy kilogram of body weight per day. So, that’s like your ideal weight in pounds, multiplied by four, and then divided by ten. So, someone whose ideal weight is 100 pounds may require up to 40 grams of protein a day. On average, they probably only need about 30 grams a day, which is .66 grams per kilogram, but we say 0.8 or 0.9 because everyone’s different, and we want to capture most of the bell curve.

People are more likely to suffer from protein excess than protein deficiency. The adverse effects associated with long-term high protein diets may include disorders of bone and calcium balance, disorders of kidney function, increased cancer risk, disorders of the liver, and worsening of coronary artery disease. Therefore, there is currently no reasonable scientific basis to recommend protein consumption above the current recommended daily allowance, due to its potential disease risks.

Which type of protein is better for our kidneys? Powerful anti-inflammatory drugs can abolish the hyperfiltration and protein leakage response to meat ingestion, suggesting that animal protein causes kidney stress through inflammation. Here is the research. 

Between 1990 and 2010, some of our leading causes of death and disability haven’t changed. Heart disease was the leading cause of loss of life and health then and remains the leading cause today. Some things got better, like HIV/AIDS, but others got worse, like chronic kidney disease, a doubling in the tens of thousands of deaths and the hundreds of thousands whose kidneys fail completely, requiring kidney transplants or lifelong dialysis. About one in eight of us now have chronic kidney disease whether we know it or not and, most of those with kidney disease don’t know it, about three-quarters of the millions affected are unaware their kidneys are starting to fail. This particularly worrisome given that early identification provides an opportunity to slow the progression and alter the course of disease. So, what can we do about it?

The Western-style diet is a major risk factor for impaired kidney function and chronic kidney disease, also known as the Meat-Sweet Diet, or Standard American Diet, causing an impairment of kidney blood flow, inflammation, and subsequent leakage of protein in the urine, and a rapid decrease in kidney function. Table sugar and high-fructose corn syrup are associated with increased blood pressure and uric acid levels that can both damage the kidney and saturated fat, trans fat, and cholesterol found in animal fat and junk food negatively impact kidney function as well. The consumption of animal fat can actually alter the structure of the kidney and animal protein can deliver an acid load to the kidneys, increase ammonia production, and damage the sensitive kidney cells. That’s why restricting protein intake is recommended for preventing kidney function decline, though it may be animal protein in particular, not just protein in general; so, the source of the protein, plant versus animal, may be more important than the amount regarding adverse health consequences.

Animal protein intake has a profound effect on normal human kidney function, inducing what’s called hyperfiltration, increasing the workload of the kidney.

This may help explain why our kidneys fail so often. Unlimited intake of protein-rich foods, now generally regarded as “normal,” may be responsible for dramatic differences in kidney function between modern human beings and their remote predecessors who hunted and scavenged for meat here and there. Sustained, rather than intermittent, excesses of protein require us to call on our kidney reserves continuously, causing a kind of unrelenting stress on our kidneys that can predispose even healthy people to progressive kidney scarring and deterioration of kidney function. It’s like always revving our engine into the red. On the other hand, administration of an equal quantity of vegetable protein does not appear to have the same effects.

Eating meat, for example, increases the workload on the kidneys within hours of consumption but, apparently, taking care of plant protein appears to be a cinch. This was done with beef, but any animal protein will do. Eat a meal of tuna fish, and you can see the increased pressure on the kidneys go up, again, within just hours, for both non-diabetics with normal kidneys and diabetics with normal kidneys. If, instead of having a tuna salad sandwich, you had a tofu salad sandwich with the same amount of protein, no effect and, same thing happens with eggs and dairy protein, both in people with normal and diseased kidneys.

Short-term studies have indicated that substituting plant proteins, like soy, for animal protein is associated with less hyperfiltration and protein leakage, therefore, slowing deterioration of kidney function. However, the long-term effect had not been adequately studied, until this study: A 6-month, double-blind, randomized, placebo-controlled trial, soy versus dairy protein, and the consumption of whole soy tended to preserve renal function, kidney function, compared with milk in individuals with lowered renal function. Similar results were reported in diabetics. Even just giving isolated soy protein appeared to make things better, compared to dairy protein, which made things worse.

Once one’s kidneys have deteriorated to the point that they’re actively losing protein in the urine, a plant-based diet may help turn it off and on, like a light switch. What is going on? Why does animal protein cause that overload reaction, but not plant protein? It appears to be an inflammatory response triggered by the animal protein. We know this because administration of a powerful anti-inflammatory drug abolishes the hyperfiltration, protein leakage response to meat ingestion, confirming the role of inflammation in the impact of animal protein on our kidneys.

Only about one in 10,000 people make it to be 100 years old, which raises the question: What’s their secret?  Well, in 1993, a major breakthrough in longevity research was published: A single genetic mutation that doubled the lifespan of a tiny roundworm. Instead of all being dead by 30 days, the mutants lived 60 days or longer. This lifespan extension was the largest yet reported in any organism.

This Methuselah worm medical marvel is the equivalent of producing a healthy 200-year-old human—all because of a single mutation? That shouldn’t happen; I mean, presumably, aging is caused by multiple processes, many genes. How could just knocking out one gene double the lifespan?

What is this aging gene anyway, this gene that so speeds up aging that if it’s knocked out the animals live twice as long? It’s been called the Grim Reaper gene. What is it? It’s the worm equivalent of the human IGF-1 receptor and mutations of that same receptor in humans may help explain why some people live to be a hundred, and other people don’t.

So, is it just the luck of the draw whether we got good genes or bad? No, we can turn on and off the expression of these genes, depending on what we eat. Three years ago, I profiled a remarkable series of experiments about IGF-1 (insulin-like growth factor 1), this cancer-promoting growth hormone, released in excess amounts by our liver when we eat animal protein. So, men and women who don’t eat meat, egg white, or dairy proteins have significantly lower levels circulating within their bodies.

Switching people to a plant-based diet can significantly lower IGF-1 levels within just 11 days, markedly improving the ability of women’s bloodstreams to suppress breast cancer growth, and then kill breast cancer cells off.

Similarly, the blood serum of men on plant-based diets suppresses prostate cancer cell growth about eight times better than before they changed their diet. This dramatic improvement in cancer defenses is, however, abolished if you add back just the amount of IGF-1 banished from their systems because they were eating and living healthier.

This is one way to explain the low rates of cancer among plant-based populations: the drop in animal protein intake leads to a drop in IGF-1, which leads to a drop in cancer growth. An effect so powerful, Dr. Dean Ornish and colleagues appeared to be able to reverse the progression of early stage prostate cancer without chemo, surgery, or radiation—just a plant-based diet and other healthy lifestyle changes.

Now, when we’re kids, we need growth hormones to grow. There’s a rare genetic defect that causes severe IGF-1 deficiency, leading to a type of dwarfism—but also apparently makes you effectively cancer-proof. Not a single death from cancer in about 100 individuals with IGF-1 deficiency. How about 200 individuals? None developed cancer. See, most malignant tumors are covered in IGF-1 receptors but, if there’s no IGF-1 around, then they may not be able to grow and spread.

This may help explain why those eating low-carb diets appear to cut their lives short but not just any low-carb diet—specifically those based on animal sources, whereas vegetable-based low-carb diets were associated with a lower risk of death.

But look, low-carb diets are high in animal fat, as well as animal protein. So, how do we know it wasn’t the saturated animal fat that was killing people off and it had nothing to do with the protein? What we need is a study that just follows a few thousand people and their protein intakes for 20 years or so and just see who lives longest, who gets cancer, who doesn’t. But, there’d never been a study like that—until now.

Six thousand men and women over age 50 from across the U.S. followed for 18 years and those under age 65 with high protein intakes had a 75% increase in overall mortality and a fourfold increase in the risk of dying from cancer–but not all proteins, these associations were either abolished or attenuated if the proteins were plant-derived, which all makes sense, given the higher IGF-1 levels among those eating lots of animal protein.

The sponsoring university sent out a press release with a memorable opening line: “That chicken wing you’re eating could be as deadly as a cigarette,” explaining that eating a diet rich in animal proteins during middle age makes you four times more likely to die from cancer than someone with a low-protein diet—a mortality risk factor comparable to smoking cigarettes. And when they say low-protein diet, what they actually mean is just getting the recommended amount of protein.

“Almost everyone is going to have a cancer cell or a pre-cancerous cell in them at some point.” The question is, “Does it progress?”, said one of the lead researchers. That may depend on what we eat.

“The question is not whether a certain diet allows you to do well in the short term”, one of the researchers noted, “but can it help you survive to be 100?” It wasn’t just more deaths from cancer. Middle-aged people who eat lots of protein from animal sources were found to be more susceptible to early death in general. Crucially, the same did not apply to plant proteins, like beans, and it wasn’t the fat, but the animal protein that appeared to be the culprit.

What was the response to the revelation that diets high in meat, eggs, and dairy could be as harmful to health as smoking? Well, one nutrition scientist replied that it was potentially dangerous. It could damage the effectiveness of important public health messages. Why? Well, a smoker might think, “Hey, why bother quitting smoking if my ham and cheese sandwich is just as bad for me?’”

It reminds me of a famous Philip Morris cigarette ad that tried to downplay the risks by saying, “Hey, you think secondhand smoke is bad, increasing the risk of lung cancer 19%; well, hey, drinking one or two glasses of milk every day may be three times as bad—62% increased risk of lung cancer. Or doubling the risk frequently cooking with oil; or tripling your risk of heart disease eating non-vegetarian; or multiplying your risk six-fold eating lots of meat and dairy.” So, they conclude, “Let’s keep some perspective here.” The risk of cancer from secondhand smoke may be well below that of other everyday activities; so, breathe deep. That’s like saying, yeah, don’t worry about getting stabbed, because getting shot is so much worse. It’s like saying if you don’t wear seat belts, might as well have unprotected sex. If you go bungee jumping, might as well disconnect your smoke alarms at home. Two risks don’t make a right.

Of course, you’ll note Philip Morris stopped throwing dairy under the bus once they purchased Kraft Foods.

To see any graphs charts, graphics, images or studies mentioned here, please go to the Nutrition Facts podcast landing page. There you’ll find all the detailed information you need plus links to all the sources we cite for each of these topics.

NutritionFacts.org is a nonprofit, science-based, public service, where you can sign up for free daily updates on the latest in nutrition research via bite-sized videos and articles.

Everything on the website is free. There’s no ads, no corporate sponsorship. It’s strictly non-commercial. I’m not selling anything. I just put it up as a public service, as a labor of love, as a tribute to my grandmother whose own life was saved with evidence-based nutrition.

Thanks for listening to Nutrition Facts. I’m Dr. Michael Greger.

This is just an approximation of the audio, contributed by Allyson Burnett.

31 responses to “How Much is Enough Protein?

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  1. How much plant-based proteins is enough? It does not say it here. Please, why do not make some podcasts and videos for people who altredy eat WFPL.

    1. Hi Rita, I am one of the volunteer moderators on the site. You have a good question about how much protein is enough.The protein requirements is based on age and activity level and any other medical history. Our U.S. government’s recommended daily intake (RDA) is at least 0.8 to 1.0 gram of protein for every kilogram of ideal body weight, which means that a 154-pound person (70 kg) needs at least 56 to 70 grams of protein a day. “Some people may benefit from a bit more protein than this minimal level, because of activity or one might have to adjust the protein level based on any medical conditions. So it is a good idea to discuss your optimal protein intake with your physician and dietitian as a dietitian will be able to assess your needs based on your age and the medical history.

    1. Have you tried subscribing to this podcast with the iOS’s Podcasts app (or comparable app for Android)? With Podcasts you can choose between 1/2×, 1×, 1½×, and 2× playing speeds. Alternatively, you can subscribe to this podcast with Stitcher app (available for both iOS and android) which offers 1/2×, 1×, 1.25×, 1.5× and 2× playing speeds.

  2. Sometimes people’s scholarship is lacking and doctors like Michael Greger, M.D. like other M.D., PhD’s and RD’s follow the crowd without researching protein values. The original government protein research done in the 1970’s showed that 37 grams were needed and outside research showed that 36 grams were needed. But the government has to submit these findings to the public and before they did they decided to bump the protein values up to make sure everyone had enough, so they bumped it up to 45 grams. The public got involved in the debate and the meat and dairy’s influence bumped it up to 54 grams for the average 150 lb male. Research done on the Humza’s and other research groups in Germany showed it was around 28 to 30 grams. Later research done by the USDA and the Registered Dietetic group showed it was 36 grams for vegans (who only need 1,600 calories), 45 grams for vegetarians (who only need 1,800 calories) and 54 grams for meat-eaters (who need 2,000 cal.) this was published in a peer review journal study. I have these journals and more in my books on plant-based diets; which are on Amazon. Please inform Dr. Greger on these facts. Peace Jim Tibbetts

    1. So vegans only need 1600 kcal/day !!! Wonderful, since I need far less actually, and fell great. Height 1.7m Weight 48/49 kg. So is my plant-based protein (grains, beans and green veggies including the high-protein green tea leaves) target 37g/day? Am I getting it right?

      1. Hi, Rita. At 1.7m and 49 kg, your BMI would be 17, which is underweight. If you are consuming less than 1600 kcal/day, you are may not be getting enough nutrients, and may be at increased risk for osteoporosis. You did not say how old you are, nor how active you are, which are factors in determining nutrient needs. Given the limited information you have provided about yourself, I think you might be wise to increase your caloric intake, and to shoot for at least 1700 kcal/d, and at least 39 g/d of protein from whole plant food sources. I would be interested in more information about the high-protein green tea leaves you mention, as I am not familiar with this. I hope that helps!

        1. I am 58 years old. Eating 1700kcal is way too much.I would not feel good after so much food. I tried in the past and definitely I feel bolated and stiff with more than 1200/1300 kcal/day. Activity is moderate: 90 minutes Iyengar yoga in the morning and 30 minutes daily walk wih the dog (slow walk !!) I am checking nutrients with USDA database and it seems I am overall fine. I only was just wondering how much plant protein intake was needed since all of the videos only mention meat protein, which is kind of ridiculous in a site like nutritionfacts.org which is advocating WFPB diet!!! Whereis the logic to advise 37g of animal proteins and at the same time saying you shoud not eat animals ?!!

    2. I’m interested in learning more about this. I’ve been WFPB for about three years, happily ignoring protein amounts. Recently, for reasons I won’t get into, I’ve been warned that I should be getting much more protein. When I analyze my current eating habits, I usually get 70+ g/day, mostly from beans. But I’ve been told that at my age (66) my ability to use dietary protein is reduced, and I should be consuming at least 100 g/day. That’s a lot of beans. I’m certainly not aware of anything in my health that would indicate lack of protein, but maybe I don’t know what to look for.

  3. I love all your material!
    My question regards protein requirements for athletes; how much additional protein does a triathlete need, assuming a 5-7 day workout schedule including running, swimming, biking and weight lifting, an hour per day on average?
    Many Thanks!

    1. Hi, Wiglef. As an athlete, you need more calories, but the proportion of protein does not necessarily need to increase. You have not given me enough information about you to fully answer your question. Use this free online tool https://www.nal.usda.gov/fnic/interactiveDRI/ to calculate your nutrient needs based on your age, gender, height, weight, status with regard to pregnancy and lactation, if female, and activity level. If you are eating a whole food, plant-based diet, and eating enough calories for your activity level, then you are highly unlikely to be deficient in protein. Adapt the Daily Dozen https://nutritionfacts.org/app/themes/sage/dist/images/book/daily-dozen_6c40d3eb.jpg to meet your caloric needs, and you should be good to go. I hope that helps! There are many vegan athletes who are making this work for them. You might want to check out: http://www.veganbodybuilding.com/, http://www.brendanbrazier.com/, http://www.veganmuscleandfitness.com/, http://www.richroll.com/, http://www.nomeatathlete.com/, http://vegcoach.com/, just to name a few. I hope that helps!

    1. Hi, Marisa. Please see my answer to the related question above for more details. The gist of it is that athletes need more calories. If, for example, a person is eating roughly 80% of calories as carbohydrate, 10% as fat, and 10% as protein, then increasing calories would increase protein in the same proportion. Calculate your caloric needs for your activity level, and adapt the Daily Dozen to meet them. I hope that helps!

  4. Dr. Greger, I too, would really love for you to talk about plant-based athletes as well. Especially those of us who strength train and want to add muscle mass. I know what a lot of other sources say, but I’m interested in your viewpoint.

    1. Hi, Josh. This seems to be the big question right now. I gave a comprehensive answer above, and a list of resources. I will certainly let Dr. Greger know that interest is growing in this topic, and request that he do a video focusing on it. Meanwhile, please read my responses to earlier related questions on this page. I hope that helps!

  5. Dr. Greger, I’ve been directed to this NIH study at https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1262767/ which I’m sure you’ve read. It’s being used by some to state the exact opposite of what you’re saying in this podcast. Is it possible to give a short reply as to whether they are misusing this study, or why this study actually backs up what you’re saying in your podcast? Perhaps there is a difference in getting the protein from eating meat and getting it from protein powder (which wouldn’t have the negative effects of the animal fat)???

    1. Hi Mike,
      You ask some good questions. The research review that you cite is over 10 years old and focuses on the effects of dietary protein and kidney function. Dr. Greger has address this topic in multiple posts about protein and kidneys: https://nutritionfacts.org/?fwp_search=protein+and+kidney&fwp_content_type=video His posts cover research that is much more recent that what was reviewed in the paper you cited.

      There are many factors to consider when determining whether ‘protein’ is damaging to the kidneys, and not only is the state of the kidney’s health one of them, but also the amount and the source of the protein.

      The paper you cited does not really distinguish between animal and plant protein and this appears to have an important effect, because the animal protein is likely to create a more acidic and inflammatory state in the body, whereas the plant sources of protein are not. So any study that looks at simply OVERALL protein without differentiating between the source, is very likely to miss an effect. If study participants consumed a large amount of mostly plant-based protein, and no adverse effects on kidney function were seen, it’s likely because the plant proteins do not elicit the same effects and a study using high amounts of animal-based proteins might find a different outcome.

      In the podcast, Dr. Greger notes: “That’s why restricting protein intake is recommended for preventing kidney function decline, though it may be animal protein in particular, not just protein in general; so, the source of the protein, plant versus animal, may be more important than the amount regarding adverse health consequences. Animal protein intake has a profound effect on normal human kidney function, inducing what’s called hyperfiltration, increasing the workload of the kidney.“

      Another thing to consider is the definition of ‘high’ protein. This can vary greatly. It appears that the RDA amount is sufficient for most people, but there are some people who get more and need more.The paper you cited noted that “Poortsmans and Dellalieux [93] found that protein intakes in the range of ~1.4–1.9 g/kg/day or 170–243% of the recommended dietary allowance did not impair renal function in a group of 37 athletes. We found no data in the scientific literature to link high protein intakes to increased risk for impaired kidney function in healthy, physically active men and women.”

      So the researchers are pointing out (without distinguishing between source of protein) that people seem to be able to safely consume 50% or up to 100% (double) the RDA for protein. And that’s true, and some people, especially endurance athletes and novice weight lifter, may need that much.

      BUT be careful in assuming that this is evidence that a ‘high protein diet’ is safe. Because what constitutes a high protein diet today—for example a Paleo plan, may in fact give someone 400 to 600% of the RDA—and coming mostly from animal sources. From what I have seen of the literature there is not sufficient evidence to say at all that this is safe—or easy on the kidneys. And this review that you cite, does not recommend this amount nor cite evidence that it’s harm-free. If you read The China Study, you will also note that Dr. Campbell found that higher amounts of plant protein did not appear to trigger or promote cancer growth like even small amounts of animal protein did.

      There are certainly many more studies that need to be done to ascertain the differences and effects of differing amounts, but it appears that plant protein sources are healthful, while there are areas of concern regarding consuming animal proteins.

      – nutrition professor and volunteer moderator, ‪ Martica Heaner, PhD‬‬‬‬‬‬‬‬‬‬‬‬‬

  6. Dr. Greger, You state that milk has hormones which is cancer promoting. Doesn’t soy have hormones as well? Dr. Gundry has soy as one of his DO NOT EAT foods because supposedly the hormones in soy makes you retain fat. How can two doctors have opposite opinions of soy? I would like to be reassured about adding soy to my diet.

    1. Hi Karla: Thanks for your question! You can find all the evidence Dr. Greger has pulled on soy here. It’s important for you to be comfortable with your food choices. I’ll let you review the info and make a decision that’s best for you and your body!

  7. Dr Greger, I am a medical student and I was thought that animal proteins are of the highest quality and that plant proteins are of lower quality. My question is: if this statement is actually true and if the body can regenerate and create new healthy cells (given the fact that functions are made by the proteins in the organism) if the protein is not of the best quality? Is the plant protein intake enough? Thank you very much!

  8. Teodora, the idea that animal proteins are better or more complete than plant protein is very clearly explained by a dietitian we respect here at NutritionFacts.org Jeff Novak. I think he does a great job of explaining some myths about protein and how they originated. I hope you find this helpful and it gives you confidence in knowing plant protein is not only just as good but in so many ways preferable for human nutrition.

  9. So based on this study that was recently released, “meat proteins” are associated with increased risk of heart disease. No surprise.

    I’m still unclear though as to why? Could someone explain the mechanism by which animal protein increases one’s CVD risk?

    Also, I don’t see where they specify which “meat protein” they looked at in the study. Does this include Casein?

    Thanks fam!

  10. Hello,

    I belive that, sure, ~40g of protein per day for a smaller aldult male is probably enough, but I have a lingering question about protein requirement for muscle protein synthesis(MPS). Correct me if I’m wrong, but I’ve come to learn that in adulthood, with less hormones now than as a teenager, that MPS can be naturally triggered 2 ways: Exercise; or Diet, specifically, a bolus threshold of ~2.# grams of leucine at one meal, equating to maybe 30g animal, or 50g vegan protein, to trigger mTor, and in turn, leading to MPS.

    With this understanding: In theory, if we exercise regularly, then perhaps we shouldn’t need to trigger MPS via diet since it has already been triggered by the exercise. However, the consensus among bodybuilders is that we should be trying to use both exercise AND diet to stimulate MPS as often as possible. It seems that trying to trigger mTOR/MPS at almost every meal via diet means that we must consume so much protein (well above 100g) which may be unneccesay and could increase our risk of disease.

    So, my question is this: Should athletes looking to put on muscle be trying to trigger mTor via high bolus protein intake? or should we only rely on the exercise to trigger MPS, and forget about trying to trigger MPS via diet?
    I’m worried that solely relying on exercise to trigger MPS may build muscle too slowly.

  11. This has been evaluated extensively in many clinical studies. There is NO evidence that an endurance or resistance training athlete needs any more protein than anyone else (0.8-0.9gm/kg body weight per day.) Keep in mind that even a resistance training athlete is building VERY little muscle on a daily basis and this will absolutely cap/stop after a year or two of training regardless of intensity.

    Dr. Ben

    1. Hi Ben/Jeremy,

      It may well be that athletes don’t *require* more protein than anyone else, but e.g. for strength athletes, optimal gains in muscle mass and strength do require an increased protein intake. See for instance this article from Vegan Health (written by RDs): https://veganhealth.org/protein-part-2/#athletes. The books *Vegetarian Sports Nutrition* and *Becoming Vegan* talk about this as well in their respective sections on protein. The recommendations are anywhere from 1.3 to 1.9 g/kg body weight for vegan athletes.


  12. Hey,

    I recently have tried to switch to a plant based diet and even downloaded the nutrition facts daily dozen app to track my food.

    I find that the high carbs and fiber in the diet upset my stomach but I am training for a half marathon and need a ton of food and nutrients.

    I find it really hard to feel strong without a little cheese, fish or eggs. I am 100% a believer in Nutrition facts but am really struggling to follow the advice without feeling hungry or weak or extremely bloated.

    I am woman around 5’4” 122 pounds, 28 years old. I try to eat 1,400 calories on sedentary days and up to 2,000 calories on days when I run long distance.

    Any advice would be wonderful.

  13. Kat,

    Have you seen any of these video’s/links: https://www.youtube.com/watch?v=dgiPdwKaaig or perhaps https://www.businessinsider.com/vegan-athletes-and-why-they-changed-their-diet-11. Or consider Neal Bernard’s MD video: https://www.youtube.com/watch?v=WQQhxedw780 ?

    These are examples of some of the high functioning vegan athletes who clearly are ripped and in great shape.

    My I also suggest that while you’re making the transition you consider adding some digestive enzymes to your meals. See if the bloat resolves. As another consideration you might not be tolerant of some foods, so check if elimination of say, soy or another food group helps with your symptoms.

    In terms of density it’s can be a bit of a struggle at first and using higher levels of nuts and seed along with avocados and some extra oil on the veggies may cut the hunger significantly.

    Diets are about finding the right combination of foods that both give you the energy needed, along with great bodily function.

    Hope this helps to find the balance. Nice job on the exercise level !

    Dr. Alan Kadish moderator for Dr. Greger http://www.Centerofhealth.com

  14. Hi

    I have recently switched to a plant based vegan diet and am looking to achieve optimal gains in strength and muscle mass through resistance training. I have a question about plant based protein and its affect on IGF-1. It is clear that consuming high amounts of animal protein increases IGF-1 and potentially causes cancers and reduces longevity. Are there any studies based on vegans consuming high amounts of plant based protein and their IGF-1 levels?

  15. Here is a NFO video that will provide a reassuring answer for you with the studies to back it up: https://nutritionfacts.org/video/protein-intake-and-igf-1-production/ Good for you in learning about the healthiest way to make those gains in strength and muscle mass. Learning about vegan body builders might be reassuring as well.
    https://gamechangersmovie.com/benefits/maximizing-performance/gaining-muscle-and-strength/ (check out the movie too!)

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