Doctor's Note

So here’s where we are in the five-part smoothie series: In the first video Are Green Smoothies Good for You? I talked about the enhanced nutrient availability absorption. Then in Are Green Smoothies Bad for You? I raised the questions about teary-eyed gut flora and intact grains, beans, and nuts. Next comes Liquid Calories: Do Smoothies Lead to Weight Gain? and finally, The Downside of Green Smoothies.

The berry experiment I start out discussing is detailed in this video: If Fructose is Bad, What About Fruit? Is there any limit to whole fruit, though? See How Much Fruit is Too Much?

Fructose bad? See:

Since just digesting food creates free radicals, we'd better be sure the food we eat is packed with antioxidants:

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  • durianmangosteen

    What about those big 5+ bananas smoothies, excessive ? What if you add berries and greens to it, acceptable then ?

    • MikeOnRaw

      I would check out the How Much Fruit is Too Much video he linked in his notes.

    • Joseph Gonzales R.D.

      I would have also recommended the video Mike posted. Bananas are higher in the glycemic index, as well as watermelon and pineapple, however that doesn’t mean they are necessarily harmful in excess. As Dr. Greger points out, “bananas in general though may actually improve blood sugars over time.” I don’t think 5 bananas is excessive, as I have heard of folks eating way more than that! However, diabetics may not want to go “bananas” with bananas, as lower glycemic choices may be more beneficial. So yes, more berries and greens added to your smoothies will make it more acceptable and balance out the bananas a bit.

      • Laurie Masters

        What??? What glycemic index chart are you looking at? I’ve always seen bananas at 52 on the GI (where LOW is below 55) … so they’re not even MEDIUM, and certainly now HIGH on the GI. I personally know diabetics who easily eat a dozen or more bananas a day … because they know, as Dr. Greger confirms (, that FAT (not sugar) causes blood-sugar metabolic disorders, by paralyzing insulin.
        See here – Healing Diabetes with Fruit:

        • MikeOnRaw

          People with diabetic type 2 already have a problem. And while that problem is due to the fat they have been taking in, they still will need to stay on top of the sugars they take in because a diabetics system isn’t working correctly anymore. So the Doctors comment to be careful with bananas really could be expanded to be careful with all fruits other then berries. Because it will take time to reverse diabetic type 2 and until that happens, you need to be careful about your diet in general.

          • Laurie Masters

            Mike, that’s actually not what diabetics report … I don’t have diabetes, but i have friends who do. If they don’t eat more fat than we need (which is very little, around 10% of calories OR LESS) then their blood sugars are fine, even if they eat dozens of pieces of fruit per day, and even if they eat table sugar (which is definitely not healthy … but it will not cause sustained, elevated blood sugar spikes). Here is a video where Dr. John McDougall explains exactly what I just said:

            DESCRIPTION: “Published on Feb 23, 2015 – Fat is the cause of Type 2 diabetes, the cure is a low-fat plant-based diet. Here Dr. McDougall discusses the considerable research showing even a diet of table sugar, white rice and fruit juice can cure Type 2 diabetes. And yet a lot of people misguidedly believe sugar is the culprit in this disease. Incredible!”

        • Joseph Gonzales R.D.

          Maybe this GI chart is off? Harvard’s list of foods with their glycemic index scores has bananas at 62. Did you read my whole comment I only said they were high, but that doesn’t really matter or tell the whole story. Plus the glycemic load is more practical. Anyway, sorry I got confused thanks for that link I agree fruit is fine for diabetics but if sugars are thru the roof I would advise more greens and beans, less fruit and grains. In the Marshall Islands this approach worked very well.

          • Laurie Masters

            Hmmm, the numbers in that Havard table do seem to differ from the tables I have used as reference. At first I wondered whether Harvard was using the alternate definition of glycemic index (both pure glucose and white bread continue to be used as reference foods), but that isn’t the case – both Harvard and my sources use the former. (For those who don’t know, glycemic index ranges approximately 50 to 100, where 100 represents the standard, which can either be defined as pure glucose or white bread.)

            When I first did this research for a talk I gave back in 2011, I used this table: Foster-Powell, K. et al., “International Tables of Glycemic Index and Glycemic Load Values: 2002.” Am J Clin Nutr 2002;76:5–56. ( There, you will see on page 30: “Banana, ripe, all yellow (USA)=51.” And on page 31: “Mean of 10 studies = 52 +/- 4.

            A quick web search yielded three other websites that also put bananas at 51 on the GI:
            1. Glycemic Edge:

            To further dispel the “fruit is high glycemic” mythology, I’ll include the data from the chart I created in 2011 (using the AJCN table referenced above). As is common in this carbophobic culture, my audience was surprised to see that, out of twelve common fruits, only watermelon is rated “high” on the glycemic index. (And notably, it’s only BARELY high at that … watermelon ranks 72 out of 100, and high begins at 70.).

            Here are the numbers (for reference, MEDIUM = 56-69; above that is HIGH and below that is LOW):
            – 22 = Cherry (LOW)
            – 38 = Apple (LOW)
            – 40 = Strawberry (LOW)
            – 42 = Orange (LOW)
            – 42 = Peach (LOW)
            – 46 = Grape (LOW)
            – 51 = Mango (LOW)
            – 52 = Banana (LOW)
            – 59 = Pineapple (MEDIUM)
            – 65 = Cantaloupe (MEDIUM)
            – 72 = Watermelon (HIGH)

            Laurie Masters, freelance editor, Precision Revision ~

          • Constantin

            Regarding bananas it’s another story . Poeople with insulin resistance should eat them when they’re still green and mixed/juiced with their favourite fruits ( could be high g/i as well ) cause of the resistant starch that have wonderful effects against type 2 diabetes and little to no fructose, and not yellow ish to brown when they’re very high in fructose and no resistant starch present .

      • Matthew Smith

        Could you please explain hypoglycemia in the context of the Whole Foods Plant Based diet? Evidently blood sugars are intimately related to many aspects of health and blood sugar crashes can create stress in any life. Even people who test as having normal blood sugars can have hypoglycemia. Thank you very much.

        • DiabetesIsCured

          Very interesting conversation here. One thing the study misses is the diet prior to those tests. Someone who ate pizza and hamburgers the night before may have insulin resistance and respond differently to fruit than a low fat raw vegan with zero insulin resistance. I personally overcame diabetes with a high fruit diet. The animal products and oils keep insulin from working properly, so my insulin response to foods was way different back when I had type 2 diabetes and A1C of 9.0. Now, I have A1C of 4.7 with no medication and my blood sugar stays around 80 fasting and stays under 100 even after eating a 500-800+ calorie fruit smoothie. So I believe GI (glycemic index) to be irrelevant, with the true importance being placed on preventing insulin resistance.

          • Willard

            That’s one heck of an amazing story. Will you please share details on how you accomplished this?

          • Joseph Gonzales R.D.

            Thanks for mentioning! The glycemic index is NOT as important as a quality diet full of whole plant foods.

          • Constantin

            That number is hard to achieve especially on fasting for a large number of people without controlled doses of vitamin c every 3 hours 8 hours of sleep plus high quality melatonin before sleep , no heavy meals for at least 2 hours before sleep maybe a slice of pineapple for the maximum hgh release in the first 2 hours of sleep and maybe capsaicin before and after sleep to bulletproof testosterone .

          • Congratulations. The GI is interesting but not really relevant for patients interested in “curing” their type 2 diabetes. Three factors and one caution are important to keep in mind… 1. fat in diet is absorbed and creates insulin resistance both in the blood and intracellularly 2. overfat individuals spill fat into their blood constantly 3. saturated fat has been shown to harm beta cells in vitro. The take home message… whole food plant based nutrition avoiding added oils especially saturated fats (i.e. present in all refined oils especially tropical oils) and to obtain a healthy body fat. After changing the diet most patients see pretty dramatic improvement in glucose values. More long term in fat loss which relates to eating low energy dense foods. Jeff Novick does an outstanding presentation on Calorie Density. The interesting thing about the GI index is that some foods that are relatively high are fine for diabetics whereas one of the lowest glycemic food… fructose in concentrated form is not helpful due to the metabolic products formed by the liver… uric acid, inflammatory aldehydes, lipids and some glycogen. Fruit intake is fine although some patients need to be concerned if they have difficulty digesting fructose, respond with elevated triglycerides or have allergies to fruit. Since there is individual variation and patients can have difficulty with certain plant foods they need to work with a knowledgable clinician. This is especially true if a person is on hypoglycemic and/or anti-hypertension medications. They need to appropriately monitor their values and adjust medications to avoid complications of too low sugar or blood pressure. Other medications may need to be adjusted as well. Congrats again on your success and taking the time to share your story. Remember to keep tuned to as the science keeps changing.

          • Thea

            Dr. Forrester: Your post mentions Jeff Novick’s Calorie Density DVD/talk. I agree that it is fabulous. I learned so much from it! I like to refer people to that talk, but according to the Jeff’s site (and Amazon), they DVD is “sold out” and they do not appear to making any more:

            If you have an “in” there, could you tell them that people would like that talk made available again? Dr. Lisle’s free youtube talk is a great accompaniment, but I feel strongly that both talks are needed for the subject to be really absorbed. I would love to be able to refer people to Jeff’s talk again.

        • Wegan

          So why is my A1C 5.6 when I already eat this way?

        • Joseph Gonzales R.D.

          I think Dr. Greger is just mentioning about a hypoglycemic dip, not full blown hypoglycemia. The key to diagnosing low blood sugar is to test it when a person is having symptoms. I am not certain people who test normal have hypoglycemia, I mean that is why doctors test for it. Does that make sense? Thanks for all your questions sorry I cannot answer this one better.

      • Constantin

        Watermelon it does have fructose “BUT” citruline blunts it :)

  • Dominik

    Apples and all grains shouldn’t be blended, but it is ok to blend vegetables, beans, berries, bananas and mangos?

    And which fruits besides apples shouldn’t be blended?

    • Tobias Brown

      What’s wrong with grain blends? Aren’t all flours essentially grain blend?

      • Julot

        Flour is never a whole food so even foods based on whole flour~

    • Joseph Gonzales R.D.

      We only know what you know about the research studies, as other fruits have not been tested to my knowledge. Apples can still be blended with other fruits, but apparently not solo. I think a wide variety of fruits (especially the berry family) ought to be included in the diet.

      • Neil

        Wouldn’t it be advisable to include amla in smoothies to help control spiking blood sugar?

      • Dominik

        Thanks, this helps alot! I usually drink a fruit smoothie (bananas, blueberries, strawberries, apples, a tsp of cinnamon and a tsp of curcuma) for breakfast. But I stopped adding dates.

  • Atom

    What about carrots? How does juicing and blending compare to eating them?

    • Doctor Dave

      I think carrots were covered in part a few weeks ago. Turns out that carrots have small crystals of carotenoids in the cells that are released with 1 min or so of blending. So, raw carrots are better blended compared to chewing. Not sure how the juicing works. I guess it depends on what kind of juicer. There are high speed juicers that oxygenate the juice and there are low speed juicers that are more like chewing called masticating juicers.

    • Joseph Gonzales R.D.

      Hi Atom. Dr. Dave is right! From this video Dr. Greger point out, “…even just regular chewing can release about ten times more, but not as much as blended. Intense cooking, boiling for 25 minutes, so damages the cell walls, that even gulping down large particles can result in significant absorption, but even then, blending may double carotenoid availability, explaining why we may be able to absorb three times the alpha and beta carotene from pureed cooked carrots compared to mashed cooked carrots. So, blending vegetables—raw or cooked—into soups, sauces or smoothies can maximize nutrient absorption.”

      Let me know if this helps?

  • Tom Zdrojewski

    What about smoothies that are just greens, no fruit? Like,for example, spinach with soy or almond milk and some cacao and ground flax?

    • disqus_t7eaNBw4l1

      check out videos 1 and 2 for that

  • Noe Marcial

    WOW.. So interesting.. i imagine that the size of the portion matters in this case, when is too much glucose in the blood that the body can not deal with it and then Hipoglucemia cames into…and the fats came to the belly too..
    so what about the big meals, when they are not wfpb? i mean it should be terrible . for example i eat a lot of salads and do pretty well with the wfpbd.. but I eat with white bread (quite alot) immediately after the meal i have a strong feeling for siesta.. it may be not an spanish gene but a hypoglycemic state? may be i can add a blueberry dessert .( mmm ) or… in place don’t eat the white bread with the meal..

    • Noe Marcial

      i wonder also how many meals a day it will be the best for the glycemic index? because if one does 3 meals the size of them are going to be bigger that if you eat smaller portion 5 o 6 times a days…

      • MikeOnRaw

        I bet such would be great questions to pose to Robbie Barbaro on one of his youtube videos or his website or snapchat (mindfuldiabetic). He is a type 1 diabetic who eats mostly raw fruits and vegetables and monitors his gluclose regularly. I’m sure he has a good feel for how much of anything he eats affects his metabolism.

        • Laurie Masters

          Robby (my longtime friend) eats ONLY raw, and at least 90% of his calories come from fruit. He teaches people how to reverse type 2 diabetes and manage type 1 diabetes very effectively, using either an all-raw program (fruit based) or a cooked program (starch based). Both work fantastically well, as long as you don’t eat what CAUSES insulin resistance (more than 10% of calories from fat).

  • HaltheVegan

    I’m still wondering about the storage of blended Fruits and Vegetables. Does the refrigerated storage of blended F & V for a few days decrease their nutrient content significantly? How about frozen? Does the frozen storage of blended F & V for a few weeks decrease their nutrient content significantly? Are there any research studies showing graphs with nutrient content vs storage time? Or just an educated opinion of an expert at this point would be a help.

    • MikeOnRaw

      I’ve been pondering this myself as job change has me away from a blender at lunch times. Fresh fruit is pretty easy to bring in to work for lunch but when winter comes fresh is tougher, so I generally was doing lunch smoothies. My gut is telling me that due to the metal blades in blenders that oxidation will be taking place and the longer it is sitting the more oxidation takes place.
      Like you I don’t know at what point the oxidation becomes a problem for the nutritional content of the food. My guess is freezing would be best for long storage.

    • Joseph Gonzales R.D.

      Look for discoloration (browning), like when an apple sits after one bite and gets brown. Any time vitamin C is in the mix foods are better preserved, hence why we see ascorbic acid/citric acid/vitamin C added to many products. I would expect the same for smoothies, that adding a source of citrus or vitamin C may prolong the oxidation process. I see lots of information about only keeping them for 24 hours but there is nothing in stone. Let’s see if others can find research on this.

      I see no problem keeping the fridge for a few days or freezing. I would not expect a significant loss in nutrients, even with freezing. Of course if it become odorous and unappealing throw it out like you would any food.

      • HaltheVegan

        Thank you for the reply. For convenience, I like to make several blender containers at a time for use later, but wasn’t sure how much nutrition was being lost by doing that. It stands to reason that freezing would be best. And I hadn’t previously thought about the citrus addition for vitamin C, but sounds like a good idea. I do use citrus in fruit smoothies (as well as plenty of berries), and tomatoes in vegetable smoothies/soups.

    • mbglife

      I’m not an expert, but I did lots of research years ago when I used to juice F&Vs. Frozen hold nutrients the best. It degrades “rapidly” in the fridge (however fast that is). Don’t freeze in glass as it tends to break. In fact, and closed container should have an air gap until frozen, then sealed. I used to pour juice into food grade silicon ice cube trays and pop a few out when I wanted them.

  • MikeOnRaw

    It appears that what the science is saying, is something that all good technology people say, it depends. I took to heart the original video I saw when starting this lifestyle on January 1 2015. The If Fructose is Bad, What About Fruit and the studies behind it clearly indicated that “berries” can have a significant positive affect on insulin response. As such nearly every single smoothie I eat (all 64oz) includes some frozen or fresh berries (strawberry, raspberry, blueberry). Sounds like the mangos and bananas don’t hurt either.

    • Steven

      Have you checked your blood sugar to confirm the berries are ok? I hate to be a spoiler, but berries spike my blood sugar just like any other fruit.

      • Noe Marcial

        but how it is the hypoglycemic 120 minutes after berries it is as bad as when you eat sugar?

      • MikeOnRaw

        Why yes, yes I did. I had a group of friends that saw what I was eating and felt i was killing myself. Turns out I’m doing just fine and I videoed the results of my tests

  • Brent

    Wow, now that was helpful information! Thanks!

  • disqus_t7eaNBw4l1

    Are frozen berries okay? fresh are quiet expensive to blend such large quantities to mask the greens’ taste and mango I cant find all year round. Also I am not quiet clear here as berries were emphasized, so green smoothies with bananas are okay i always assumed blended bananas did the whole burst of fat, high/low BCG??

    • MikeOnRaw

      I use a 1/2-1 cup of frozen mango, 1/2 – 1 cup of frozen strawberries (or raspberries or blueberries or some combination). Then 30-60 grams of baby spinach or kale. And then as many bananas as can fit in the blender (5-8) after that stuff is there.
      Seems to work perfectly fine.

    • Joseph Gonzales R.D.

      Berries are good to eat, fresh or frozen. When berries and greens are added to smoothies it just boosts the quality. Some of these studies looked at just apples or just bananas, so the idea is that whole leafy greens, mango, pear, etc (any whole fruit–especially berries) is preferred.

      • Charzie

        I’m gonna guess (hope?) that this might apply to food in general…mix it up for best results. I don’t eat processed foods or animal products and when my grandkids visit they know there won’t be any meat or junkfood on the menu, but I also don’t want to totally buck their familiar “food” items, so I came up with a kind of acceptable compromise…when met with resistance. For example, the tasty but totally disgusting ramen soup request was dismaying, but instead of refusing, I used it as a base for lots of beans and veggies, and because it was a known entity, it was acceptable yet a way to get them to eat things they would normally disdain. Not that I was thrilled about it, but hey, it has got to be an improvement. It tickled me that by the time they left (after 3 weeks of gramma education), they actually ate meatless soup without the ramen part, and came to prefer their ramen soup with a couple grated carrots and chick-peas! At least while they were here…I’m a realist, LOL, but still hoping it plants the seed!

      • disqus_t7eaNBw4l1

        thank you! but didn’t the first two videos say blended greens increased absorption??! so better?? i def understand the whole fruit thing but i just thought vid 1 n 22 concluded that blended greens were better? i will still eat whole in salads but i havent found a way to cook bitter greens that make them tasty so wanted to eat them as smoothie

    • mbglife

      My understand is that frozen fruits and veggies, including berries, usually have higher nutritional content than fresh, which declines more due to early harvests and travel time and conditions. F&Vs are usually packed at or near the harvest site. So they can grow longer in the field, then be frozen within hours of being harvested. Fresh F&Vs are more likely to be picked early to allow for shipping time. Their rate of nutrient content depends on if they are picked early or ripe and how much heat they are exposed to in transit and to the store shelf and then how long it takes and the consumer buy it. Then it sits in the person’s fridge until used. I try to buy all my berries frozen.

      And I only organic berries. Google “dirty dozen, clean 15” to see which produce has the most and least pesticide expose. Berries are always heavy with pesticides.

  • nirmitlamed

    Didn’t understand if the apple smothie that mention was with some kind of leafs or only apples.

    • disqus_t7eaNBw4l1

      for the greens check out parts 1 and 2. basically as no one consumes just green smoothies, adding apple to them wont help as u will get the burst of fat and high/low spikes and dips in blood sugar levels that are not good, but if u combine with berries then it works. whole fruits are always the best but when making green smoothies only certain type work.

      • nirmitlamed

        “if you stuck those four and a half cups of sliced apples in a blender with some water and pureed them into an apple smoothie”

        Except the word smoothie i didn’t find any other word mentioning green leafs. It only mentioning apples and water. Should i understand that it was with green leafs. I am asking that because i remember reading long time ago that adding green leafs supposed to help prevent hypoglycemic and sugar spikes.


      • Charzie

        Hey, sure some of us enjoy “just” green smoothies! lol At this tomato time of year in fact, my fave green smoothie is a tomato or two, basil, dill, parsley, whatever is ready to pick, a bunch of asst greens, a cuke, celery, a spoonful of miso for salt, flavor and probiotics, and TBS of flax or chia or oats to keep it all in suspension, a few almonds or any nuts, sometimes a dash of Tabasco, and whatever else I have on hand…peppers, radishes, avocado, carrots, etc. Almost instant summer soup, eat it with a spoon! Despite the blending controversy, I feel it is still better occasionally than cooking it, because I can almost feel the buzz it gives me. Maybe imagination, but the placebo effect works too!

        When my sweet tooth speaks up, my fave is to buzz a 1/2 cup or so of oats and a few nuts, raisins and/or dates in the blender, add water or plant milk and soak for a bit…Throw in a a small carrot or even a chunk of squash, pumpkin or sweet tater, a few (usually frozen) berries and a frozen banana, cocoa, (or PB2…a de-oiled PB and cocoa powder) ground flax, cinnamon, or what ever spices I’m in the mood for (ginger, coriander, cardamom, nutmeg, etc), ice and a small handful of mild greens.

        Last but not least, my “disgusting” current answer to my coffee with non dairy creamer addiction option. A half cup of strong coffee into the blender with heated plant milk, a TBS of ground oats, some flax and nuts, cocoa powder, a paste made of dates, turmeric, and sometimes spices or an extract like hazelnut, almond, vanilla, etc.. Drinking “thick” coffee is interesting, but I am loving this creamy, healthier option more and more!

        • Thea

          Charzie: Wow, that’s hard core. And very cool.

          • Charzie

            I am kind of a weirdo Thea, but I get a kick out of challenging my preconceptions and “limits”… it can be either enlightening…or scary! LOL!

        • Johanna

          Charzie, very interesting post. Thanks for sharing what you do! Also, I agree that one can get a “buzz” from green smoothies. I have experienced that, too. I’d like to know why that happens. Dr. G, is it the effect of the plants opening up our arteries or something?

    • Joseph Gonzales R.D.

      I think it was only apples.

      • nirmitlamed

        Thanks, thats what i thought!

  • Roman Firnkranz

    I am a little bit disappointed and maybe i don’t get the point, but the title is “Green Smoothies: What Does the Science Say?” right, so i expected some science information about green smoothies, fruits + green leafy vegetables and not information about fruit juice and fruit smoothies.

    What do you guys think?

    • MikeOnRaw

      The entire series has the information I think you were looking for here. I don’t think anyone has been saying that blended vegetables are a problem. Nearly all the concern is about blended fruits due to the sugar content and the current “sugar” fear going on in the nutrition world. The science in this video showed that just having “fiber” is not enough to fully blunt the over active glucose response. But some fruits have things in them (shown in this video to Bananas, Mangos and Berries) that benefit glucose response even when blended up. So blended apples? Not your best choice. Blended bananas, mangos, and berries? A winning combination. So if you are going to make a green smoothie with a bunch of apples, maybe throw a hand full of berries in with it.

      • Roman Firnkranz

        Thanks Mike for your helpful response. What i meant is studies directly about green smoothies. Fruits in combination with green leafy vegetables. So far (the first 3 videos) we have only been talking about blending single ingredients and making conclusions to green smoothies. Is that really science about green smoothies?

        But maybe there are some effects, which occur, when when we blend both together, fruits and green leafy vegetables, which we are not thinking about now. Because that’s what critics always mention about green smoothies, there’s no science directly about green smoothies. We are just arguing on the higher fruit and green leafy vegetable consumption!

        • MikeOnRaw

          So far it appears that science is sticking to limited ingredients in their test. It is like they are looking to isolate a single actor in the behaviors they see. Dr. Greger can only show us what is available in the literature. My gut, and reading of many of the studies referenced in videos here seem to indicate that there isn’t any one signal food that will fix us all. It seems to remain what we’ve heard for ever, eat a variety of foods. The only real change that seems key is that our variety of foods should come from whole plant foods. Not processed, not animal. You can get a real sense of that from Dr. Greger when you watch some of the various interviews he has done with people, either video or podcast. His responses to various questions all along the lines asked her show that idea of eating a variety of plants is important.

    • nirmitlamed

      Exactly what i was thinking. the article is not talking about what happens when combine fruits and vegetables.

  • Eric

    I know when I tested this with 5 bananas and 2 cups of spinach (eating them whole over an hour versus sipping them blended over an hour), eating them whole only brought my blood sugar to 94. Sipping them blended skyrocketed my blood sugar to 189!

    • Noe Marcial

      and 120 minutes after? how it was your sugar? are you diabetic?

  • Agness

    This information is really helpful – but I am wandering about juices: are cold pressed juices better than centrifuge juices? I read that it is but I have not seen any study that supports it.

  • Plantstrongdoc M.D.

    Don’t underestimate the power of the smoothie!!

    • largelytrue

      Do, at least for the purposes of rational scientific investigation. Most of these studies were in obese, hyperlipidemic, or diabetic individuals, and some used ‘placebo’ smoothies or sugar loading as the relevant control. The dietary background matters when evaluating the health of a particular food and the way it is consumed.

  • Astrid

    Drinking your smoothie in 6 minutes, 4 cups is that about 1 liter? is way too fast. You still need to chew on your smoothie, keep it in your mouth, move it around, make a chewing movement and then swallow. That’s the reason why I’m not done with a liter in 6 minutes, I take about half an hour at least to get it down

  • Carola

    what if you ad vegetables like spinach to the smoothie

    • Carola

      haha i will watch video 1and 2

  • Neil

    There was no (not yet anyway) discussion of nuts or seeds in smoothies. I almost always include a Brazil nut and two tbsp of ground flax seed in my smoothies, along with 1/2 tsp turmeric, 1/4 tsp black pepper and 1tsp of amla to my fruit and greens morning smoothies. I am curious to see if there is any blunting of insulin spike associated specifically with nuts/seeds. I know there is with amla and turmeric.

    • Joseph Gonzales R.D.

      Great point, as a few nuts and seeds can be added into a quality smoothie. This study observed the acute effect of nut consumption

      on plasma total polyphenols, antioxidant capacity and lipid peroxidation, finding almonds and walnuts to increased plasma polyphenol concentrations, increased the total antioxidant capacity and reduced plasma lipid peroxidation. The study didn’t look at insulin spikes but other videos and blogs on nuts show improved insulin control.

    • mbglife

      I wonder about the affects too. On the one hand Dr Greger has explained the benefits of a small amount of fat to help increase the uptake of nutrients from veggies (and I presume fruit too). On the other, Dr Robert Lustig (MD, UCSF medical school of pediatrics) who has been researching obesity for many years, believes that fat and sugar taken together overwhelm the liver because it can’t process both at the same time. However, he is normally discussing fast food & junk food sources which contain no fiber. He concludes this lack of fiber in junk/fast food (colas & fries) swamps the liver, as does excess oil from burgers & fries. But he specifically had stated that one never finds in nature foods which contain both fat and sugar together, only protein and sugar or protein and fat. That being said, I always have some nuts or seeds with my fruit to ensure nutrient uptake. But I still would like to understand it better.

      • Neil

        For some time, I felt for Lustig, who treats childhood diabetes in San Francisco. No more. I believe he now is intentionally offering lots of misinformation to sell books to low carbers. Dr Greger advocates a whole foods, plant based diet with the fats intact – in the plant foods – and not in free oil or animal fat form.

        • mbglife

          Well, as a strict WFPB vegan I get all my fats, oils and sugars from whole food sources and I do not follow Dr Lustig’s overall diet advice. But what he says about fats and sugars together makes some sense on the face of it. Which is why I’d be interested in knowing more. Plus, whole fruits, seeds and nuts all have their fiber. And that might make a difference in how much time the liver has to process them. But still, I’d like to know if simultaneous processing of fats and glucose by the liver is a concern.

          It also surprises me that Dr McDougall doesn’t agree with fats to uptake nutrients. So I wonder how he absorbs them. We seem to need more research.

          • Neil

            Dr. McDougall advocates pretty much the same dietary macronutrient ratios as Dr Greger (to the extent that Dr greger advocates a ratio!), which is to say low fat. The only significant differences might be that Dr Greger might advocate more for green leafy vegetables more than McDougall, who would suggest more starchy vegetables. The other difference would be on the topic of smoothies – where McDougall eschews them – or did – he might change his mind after this series of videos! ;)

            Keep in mind that there is some fat in spinach and kale and corn and rice. Plenty enough to help with nutrient absorption. I’ve seen Mary McDougall make dishes with tahini and whole nuts, so I think you might have a less than full impression of McDougall’s recommendations. I would suggest looking at Jeff Novick’s video on fats. It is entitled something like, “From Oil To Nuts”. If you want to understand fats better – look there!
            N.B. It is a DVD and can be found on Amazon or McDougall’s website.

          • mbglife

            Thanks for that suggestion. I followed Dr McDougall for years on his website, radio show (gone now) and books. He is a macro based, starch eater and recommends against nuts and seeds. for example, he still says to only take flax whole, not ground. I’ve read much of what Jeff says. I respect them both, but Greger is my main man. I’ve no need to go back. But that doesn’t mean I don’t still have questions about the data.

          • Charzie

            I don’t think he actually recommends against nuts and seeds per se, as much as they way we tend to consume them. He makes note of the fact that naturally, they are seasonal and come in a hard shell that takes efforts to get into, so consumption is effectively limited, which is how he said he enjoys them. In the grocery store you can get them shelled and processed any old time at all now, and because a lot of us love them, massive consumption is too easy. Even a handful of pistachios in the shell vs shelled can be a deterrent to eating too many, which is where the problem lies.

          • Charzie

            Probably another inane comment, but I was just wondering why no other animals have issues with what food to eat or how much, than us supposedly smart humans? LOL What would happen to modern humanity if the grocery stores and restaurants somehow ceased to function? Scary!

          • Jim Felder

            All whole foods contain some fat since fats are a key part of every cell wall. My understanding is that you really don’t need much fat to help transport nutrients through the gut wall. Spinach gets 15% of its calories from fat. Granted there is only 0.12 grams of fat in a cup of spinach. Even blueberries have fat with 9.5% of its calories coming from fat. Thus even if you don’t add obviously fatty food like avocado or nuts or seeds, you still get some fat when eating (or as in this case blending) whole plant foods. So you might be getting all the fat you need in a blueberry/spinach green smoothie with just the fruit and greens to aid nutrient absorbtion. Still there is lots of other reasons other than the 4 grams of fat to put a tablespoon of ground flax seeds in your morning smoothie.

          • mbglife

            Hi Jim
            Thanks for the note. I checked out your profile page. You’ve got some great posts. You’re obviously very knowledgeable. I’m with you on the fast stuff, especially since I followed Dr McDougall for so many years. My only point is that I still am unclear on the amount needed because Dr Greger states it’s differently (as does Dr Joel Fuhrman). So I’d just like some clarity. Interruption by followers is one thing. Recommendations by the good doctors is another. Perhaps this is one of the personal diet pints that Greger says he covers in his new book.

            There was a radio discussion yesterday on my local PBS station’s (, SF) “Forum” program. That was all about diabetes. They had in two health experts, one from Stanford, the other someone who is a doctor and suffers from diabetes and struggles with his weight. Both mentioned in passing that diet and lifestyle play a big part . But neither talked about proven diet treatments and just lamented the problem. When a listener called in and bad mouthed carbs both doctors and the host (who is a low carb devotee) all dumped on carbs a problem. No distinction between types of carbs or junk food. I posted a protest on the page’s disqus page and got a nice reply from someone who has been a low carb/no grains easter for 8 years and feels it’s been great for him. See:

            I referred him to you page and you posts a month ago to Wjgood and the I’d right after that, re: Barnard’s book.

            Thanks again.

  • Tiago Cartageno

    You Dr are the best!

  • Jesse

    Does juicing or blending disrupt or oxidize certain enzymes vs. eating? How does enzyme fit into the picture?

  • We love this series. We typically make huge smoothies that last 1-3 days in the fridge without any discoloration or change of taste. Smoothies catapulted us into WFPB with nary a regret for what we left out of our diets over night after we watched two year-in-reivew videos. I am sure we have company on this site who have done the same or similar. Thank you! And thank you Thea and Dr. Gonzales for your contributions. Now I can’t resist complimenting Dr. Greger on his new, clean-shaven look. VERY handsome!

  • Pressing threat to our health

    Just as concerning to me as the smoothie plant fruit dilemma, how about the fact that
    good old american citizens of ours are smoking synthetic crack, heroin, meth, pot….synthetic
    drugs from China, in the e-cig devices, and we, as their fellow citizens, our breathing in their
    second-hand vapor. They are smoking these devices in restaurants, cafes, airplanes, trains,
    public bathrooms, and their is no way to tell if it is just nicotine in them or whether it is
    synthetic meth. Kind of scary, folks. Ban these electronic smoking devices in your communities,
    this is far worse a problem than a piece of meat,fish, egg or cheese every once in a while.

    • Charzie

      I never go out in public when vaping my crack, heroin, meth, pot and synthetic drugs from China, in my e-cig devices! :P Seriously though, as an ex-smoker who was THRILLED to find a bridge to quitting that actually worked, I find it infuriating that what started off as an ingenious invention by a son to finally end a persistent addiction in his dad, is being abused as yet another way for people to harm themselves, and others by association. We are such a strange species!

  • dogulas

    What is so bad about a brief blood sugar spike? If it only lasts for a couple minutes, does that brief moment of high blood sugar really cause any problems? Those eating low fat, having good insulin sensitivity, shouldn’t have any issue dropping the blood sugar quickly.

    • disqus_t7eaNBw4l1

      its the rapid hypoglycemic drop after the spike ( both in conjunction) are not good. if u notice there is still a spike (not as high though) but it tapers off with whole fruits…if this happens on a regular basis not v good at all

      • dogulas

        Thanks! So there is no problem with a big sugar spike as long as there isn’t a hypoglycemic drop afterward (it just settles back to normal rather than going to low)?

      • dogulas

        For example, supposedly, getting spikes all the time supposedly raises your A1C level (which is associated with heart trouble).

  • Lawrence

    OFF TOPIC: American Egg Board ‘Egg-regious’ (and Possibly Criminal) Behavior

    Dr. Greger has previously informed us of the USDA’s American Egg Board malfeasance:
    But, the alleged anti-competitive and possibly criminal activity of the American Egg Board reported by Michele Simon on 9/2/2015 is beyond the pale, and her call for Congressional hearings, criminal investigations and lawsuits appear to be entirely justified. This is an absolutely jaw-dropping story:
    A summary by Hampton Creek of alleged American Egg Board criminal behavior may be found here:

    My response to this information is to suggest that any egg-eater who is not on a first-name basis with either their farmer or their hen, consider boycotting eggs. And, for all of us, consider supporting Hampton Creek by trying their products, if that is an option.

    (Disclaimer: Absolutely no vested interest of any parties in this matter, other than being a U. S. taxpayer.)

    Sorry for the interruption. And, now back to Dr. Greger’s current, excellent video.

    • Wade Patton

      My mom and her hens provided me with all the eggs I could ever eat for years-in consideration of your “first name” relationships test. And I did eat a lot of eggs from the farm (which make factory-produced eggs look like a lump of colored spit, haven’t eaten those in decades).

      Problems I found with that are 2 (dos):

      Although the birds free-range, they are also fed commercially produced feeds and I cannot trust commercially produced feeds. See video on contaminants in fish feed and how utterly pathetic the USDA can be.

      This still does not change the nature of the product to such where the nutritional benefits (and culinary delights) outweigh the nutritionally negative impacts on health. A “wonderfully produced” egg is yet an egg.

      Everyone should make this choice on his/her own, but also be provided good information, not the garbage spewed forth by the Egg Board. Problem boils back down to how much money supports the garbage, and how little supports truth and health.

  • Linda N

    I never use fruit or juices in my smoothies. Only veggies, water and a little walnut oil. Fruit smoothies would be way too much sugar for me, not to mention ridiculously high in histamine.

  • Joe Caner

    When I do get onto a smoothie kick, I always include greens, carrots, berries, mangos, and bananas with ice. It’s very tasty and I feel fantastic afterwards.

  • Wade Patton

    My old smoothie maker is now mostly employed making whole flaxseed into ground flaxseed. It also assists with frijoles refritos sometimes…need ear protection to use it.

    • georgeT

      I’m very much like you Wade. My old smoothie maker makes smoothies only during the summer. The rest of the year, it grinds flax seeds for me. I don’t enjoy drinking/eating cold or cool things when it’s cold outside – I even sometimes get sick if I do.

  • Charzie

    No science here, just a comment. I fail to see how adding lots of
    beneficial stuff together and even pulverizing it to smithereens
    wouldn’t be better for one than avoiding whatever in that mix you would
    probably omit by itself. Green smoothies are doable and a way better option for me as a lunch replacement than
    either extreme of not eating at all or eating something horrible. I
    know this group wants more specific info, and of course I’m curious too,
    but other than adding too many calories, having a regular smoothie if
    you enjoy them seems like a decent way to push the good stuff…even if
    it is processed to a degree. Personally, I find making them thicker and
    enjoying them with a spoon is a lot more satisfying than drinking them.
    (…unless they don’t come out well and I don’t want to waste them!)

    • Wade Patton

      Eating smoothies daily is a fast track to higher metabolism in my case. So I wound up skinnier than I am now and was always chasing hunger. There’s just no way to get “too many calories” in smoothies as I ate them-a quart at a time.

      I’m with you though. Eating a some smoothies in combination with WFPB (un-pulverized) eating isn’t going to “complicate” any condition or be any cause for concern. I’m sure i pitched some apples into some smoothies BITD, but was never a mainstay and with so much greens and berries along with zero oils or animal products. Simply not a concern.

      Also, I’ve since learned not to peel any bananas that go into the blender (could have been a huge time/waste saver, especially when frozen)…not going to find any studies on that (eating banana peels) are we? Nor 99% of all the forage and such that I drag in to consume and flavor things.

      • Charzie

        I NEED a higher metabolism, mine is slug-like, I am so jealous…maybe I should experiment! Did you replace meals with them, or did you add them to what you were already eating? And I heard about others consuming banana peels, it doesn’t seem to be problematic I guess? I am all for getting more food bang for the buck since I have so bucks to work with. Though bananas aren’t a favorite I do use them, and in fact I’m waiting for my own bananas to mature. Learning to grow a lot of my own food here in S. Florida, sure is different than up north in New England where I originally learned (I recently got into permaculture…food forests), but love to forage too! It expands my mind instead of my backside and gets me out into nature walking, observing, and feeling great! A whole food plant based lifestyle!

        • Wade Patton

          I was loosely (how I do it-not a “follower” type) following the 80/10/10 high-carb way of eating. Five days per week I’d eat green smoothies for breakfast, fruit snack, all fruit lunch, fruit snack, and a “light” supper which was often tortilla chips and greens/veggies/salsa. No cheese, no meat all week. I started with 2 weeks pretty much 80/10/10, then I shifted to 5/2 and it worked like crazy to drop weight. I was raking in the calories, and also working out pretty hard (which i’m not doing now, but aim to get back to.)

          I could do that over and add nuts and seeds and more starches and get more mileage out of it. I did that for year and a half or so. Fell off the wagon to quit nicotine.

          Are you working out at all? My weight started dropping so dramatically without working out when I went WFPB, that I was curious to see how far it would go without working out. It will go all the way to a healthy weight, of that I am now sure.

          I am active, averaging 1-3 miles per day on my feet-but that’s not the same as aerobic exercise. (which i get by bike nearly exclusively. yoga is good too, but for other reasons.)

          Now I’m back and doing great big thanks to NF.O!

          • Charzie

            Yep Wade, I quit the evil smoking addiction too… “cheated” with an e-cig, but it worked like no other method could. It was still easier to quit the pain meds I’d been on for years than to quit smoking! I know there are a lot of issues surrounding e-cigs, but I was a hard core failure at quitting for so long, they were a life saver for me, probably literally.
            I don’t actually “work out” but love to ride my recumbent, do a lot of digging and gardening, take long walks to forage and just enjoy nature, but because of the damage of health issues like severe arthritis, compressed disks, spinal stenosis, blah blah blah, (which I probably could have eliminated or lessened if I had access to this dietary info), I am kind of limited physically, but do what I can and enjoy it! NF rocks!

      • Charzie

        Ha, I am so jealous, I have a slug metabolism, maybe I should experiment! I’ve heard of others eating the banana peel too, not an issue I guess? I’m not a huge banana fan, but I love them in smoothies and I’m all for getting the most bang from the grocery buck, since there are so few, lol. I grow a lot of my own stuff (really into permaculture since learning about it!) I am actually waiting for my own bananas to mature here in S Florida. I’m from CT so learning gardening here is waaaay different. We had gorgeous soil that could grow about anything, here it is anemic sand so fine it won’t even soak up the water! But there are amazing plants adapted to it, gotta respect those plants! I love to forage too, it expands my mind instead of my backside! Hey, free food, awesome nutritional benefits, exercise, fresh air, entertainment, and peace, what more can I ask for! A whole foods plant based LIFESTYLE works for me!

      • Johanna

        Our (black lab) dog thinks the whole banana, including the peel, is the cat’s meow; we regretfully discovered this yesterday. Our dog also thinks butternut squash and watermelon rind are tasty–eats watermelon rind like a kind of “bone,” and half of a squash I’d left out was demolished. However, you actually eat/include banana peels in your smoothies?

        • Wade Patton

          Yep. Dang little stickers have to come off and I nip the stem completely, but no more peeling (also I only eat speckled or riper). Someone told me of a great daiquiri made with banana and peel, so I thought it must be worth trying. Can taste no difference, but speed up the process, eliminate waste and add fiber.

          My terrier loves brussels sprouts (steamed).

          • Johanna

            Thanks for your reply! I’ll have to think about the peels–seems an odd addition, but I’m thinking about it now!

        • Thea

          Johanna: So interesting! My dog loves banana, but spits out the peel. Hates it. But he loves watermelon rind. So, I eat the insides and cut up the rind into bite sized treats for training. He loves it and I get satisfaction out of not wasting anything and keeping him healthy.

  • gp65

    So is there a list of fruits which in smoothie form lead to hypoglycemia like apples as opposed to fruits like berties which are beneficial and others that are neutral?

  • gp65

    The links to Liquid calories…weight gain and The Downdide of Green Smoothies are not working

    • largelytrue

      That’s because they are being publicly released next, on a day in the future.

  • LG King

    What, no raw garlic…onion…or fresh chilies in your smoothies (with a few tablespoons of apple-cider vinaigre or lemon’ juice)…?


  • Need my smoothie to be rated. I have a 90 oz jar.

    12 oz unsweetened hemp milk
    1 banana
    1/3 bunch spinach
    4 Tuscan kale leaves
    4 Swiss chard leaves
    3 tablespoons flaxseeds
    1 teaspoon Amla powder
    Top off with frozen raspberry/blueberry/blackberry mix from Costco

    Also wondering if the flaxseed is safe for pregnant women there is some internet chatter that it might mimic estrogen but haven’t seen anything reliable.

    • Wade Patton

      Not much credible evidence is ever only internet chatter.

      I know nothing of the nutritive properties of hemp milk, but the rest looks great to my non-professional eyes.

    • Joseph Gonzales R.D.

      It’s correct, but only a precaution. Check out our info on pregnancy.
      Preformed omega 3s are preferred, and no flax in second and third trimester if you want to be extremely careful regarding preterm birth.

      • Are chia seeds while preggo are ok? With algae based DHA supplement for backup of course.

        • Joseph Gonzales R.D.

          I am not sure they’ve been tested? I Like the idea of DHA as a back up :-)

  • MIkeS

    I typically add kale or spinach to my smoothies however I am worried about the oxalates and the fact that they are goitrogenic. As a result I steam them and then use blend. Is my concern justified and will steaming them remove or neutralize the oxalates and the goitrogenic issues?

    • Wade Patton

      Do you have a history or other risk factor for kidney stones? I don’t and was fine eating spinached smoothies for nearly 2 years solid (save the weekends). I was early 40’s then. only 49 now!

      • MikeS

        No history of kidney stones but I recently tested as hypothyroid, and goitrogenic foods suppress the function of the thyroid gland by interfering with iodine uptake. I also microwaved sweet potato in my smoothies, which I found out is also goitrogenic. I’d like to know if the steaming of the kale and spinach, and the microwaving of the sweet potato will remove the goitrogens.

        • Wade Patton

          Oh I see. Hope that all works out for the best.

    • Wegan

      This is interesting about the thyroid

    • Charzie

      I have a long history of kidney stones, even consuming less animal products than anyone I knew…until I went WFPB years ago and subsequently ate a ton more oxalates…and shhhhh, no problem since! Ironic isn’t it?

  • Angelos Elarja

    If a smoothie is left in the fridge for a few hours will the vitamins and antioxidants still be there or do they get oxidized?

  • vegank

    Great information !
    The only thing with smoothies is that they make me feel sleepy.
    I only have a bout a glass full (250ml). Is this to do with the glycemic index?

  • Dasaniyum

    I was wondering, since blending increases the absorption of phytonutrients, would you run the risk of increasing heavy metal absorption as well?

  • nodelord
  • Jessie Speaks

    I was under the impression to always eat some protein with my fruits. So, in a smoothie if you add some almond butter or seed sprouts that was supposed to help balance out the sugar rush. Doctor? Thoughts?

    • Joseph Gonzales R.D.

      I would think the fiber helps slow spikes in glucose not protein, but surely you can eat protein with fruit :-) I add some flax and/or Brazil nuts (whatever I have in the fridge) to my smoothies. Here is one I like.

  • Sandra

    Would love to know about date smoothies… I have been doing dates (200 g) with blueberries (1/2 cup?) and kale (50g). I’m going to assume it’s the same as sugar water… probably I should switch the dates for bananas.

    • Thea

      Sandra: NutritionFacts has some videos that feature dates. If memory serves, the dates come off looking pretty good. I’m not sure there is a reason to shun them.

  • What I don’t like about his discussion is that he speaks about sugar INSTEAD of talking about the information about GREENS like bok choy, and greens like collards, turnips, kudzu, spinach, mint, kale. What he talks about is how the body is accepting nutrition at a faster/better rate than with chewing because the body digests juice better, Robert O Young, PhD, has found research that it digests better by 25%. So more nutrition is accepted with juicing. Joe Cross used chefs and nutritionists to help him make his documentary about juicing. No one told me that the elite juicer I bought did a terrible job with green LEAFY VEGETABLES. I bought the juicer for $300.00 and find that there are grass juicers that are only $30.00.

  • Deana Shuman

    A tad off topic, but speaking of liquid and nutrition: Dr. Greger, what’s your take on kefir? I make water kefir and enjoy it but don’t know if it’s really doing me any good!

    • Thea

      Deana: To my knowledge, Dr. Greger hasn’t specifically addressed water kefir. This same question does come up from time to time, though. So if any studies come out about water kefir, I would expect Dr. Greger to address it in the future.

      On a related note: Dr. Greger has addressed the topic of pro and pre-biotics quite a bit. The advertising for water kefir generally includes the benefits of consuming probiotics. So, there is the potential for good, though I don’t know how much of those probiotics from water kefir actually end up helping a human’s gut.

      Here’s my take: You enjoy the water kefir, and it seems *highly* unlikely (to me) that the water kefir is hurting you. So, I personally wouldn’t care if it actively helps or not as long as it doesn’t hurt. It helps you to get some water in you and has the potential to help feed or supplement your good gut bacteria.

      Hopefully Dr. Greger will be able to specifically address this question at some point in the future.

      • Deana Shuman

        Thanks for taking the time to respond!

  • Matt

    What about people with adrenal fatigue who have a hard time metabolizing sugars?

  • Geoff

    Hey Mike,

    Thanks for the videos. I’m trying to learn about healthy smoothie consumption. My girlfriend and I are really skinny people, we have been our whole lives. We eat from our local butcher and as many organic vegetables and fruits as possible, but we do start every day with a smoothie. It helps us wake up and I think it’s giving us a decent dose of vitamins and nutrients. We split this smoothie, and in it we put:

    – a cup of Spinach
    – almond milk
    – organic yogurt
    – teaspoon of flax seeds
    – teaspoon of chia seeda
    – teaspoon of hemp hearts
    – teaspoon of organic c.p. coconut oil
    – 2 tablespoons of protein powder
    – a banana
    – 1 cup of mixed berries

    Any insight would be greatly appreciated!

    • Thea

      Geoff: I noticed your recipe calls for yogurt. If you are using dairy yogurt, I would address your attention to the following’s topic page for dairy:
      and/or this view of a basic search might be helpful:

      You also mention getting food from a butcher, which I presume means that you eat meat. So, you may also want to check out: (Note that both of these topic pages were just updated!)

      With the flax and chia seeds, you don’t need any extra fat. And there are some potential issues with coconut oil that you might as well avoid:

      On the plus side, Dr. Greger would definitely endorse those berries, flax seeds and spinach.

      Finally, you mention putting in some protein powder. Depending on what that protein powder is made of and how old you are, that protein powder has the potential to have a bad effect on your health. (or it may have a neutral impact. I don’t see that you need it though.) I highly recommend the following site for a great protein 101 course:

      Hope that helps.

  • BrandonB

    I just finished reading How Not to Die. Wow, talk about evidence based! Great Read and very motivating! (get the Audio version, its read by Michael and is just like his videos… You will not be dissappointed).
    Does anyone know if powdered greens can be considered a serving of greens on Dr. Gregers Daily Dozen. They are primarily just organic greens of sevral sorts then freeze dried and grinded to a powder that you then mix in your water and drink. They seem to be the whole food as far as I can tell; not an extract. What are your thoughts?

    • Thea

      BrandonB: I’m enjoying the book too, though I’m not finished yet. But I had flipped around a little and thought I had seen some mention of freeze dried berries as retaining most the antioxidants. But I can’t find that part now and I may be mixing up a post from Joseph with the book. But my guess is that powdered greens are as good as fresh in some areas and probably lacking in others.
      My guess is that if your choice is between eating powered greens or not greens, then the advice would be to eat the powdered. Or if the powdered greens supplement your green intake, that would be a good thing. What do you think?

      • BrandonB

        I think you are right. Anything is better than nothing. I like when he mentions the concept of “what –cruciferous veggies, berries, beans– are the healthiest? The ones you will actually eat.”
        I’m just so inspired to incorporate the daily dozen, I’m curious if a doc like him would put a check mark for powdered greens.

        • Thea

          BrandonB: Great reply and I totally agree with you. And I’m curious too. What Would Dr. Greger Do? (Someone once posted on this site that when it comes to nutrition, they try to follow the WWDGD principle. ;-) )

  • Tim Wilbur

    Guys my name is Tim I am a Naturopathic Nutritionist, Homeopath, Herbalist, Social Scientist to name a few. My training in the 70’s taught me that a holistic approach was best in that taking any food, herb, ingredient from its totality will cause a chain reaction in the organism it is introduced into. Also a very little know fact these days is in FOOD COMBINATIONS: That is food families do not necessarily combine easily this comes down to compounds and mix’s, digestion problems etc. A not so good combination is fruits and vegetables. Also all melons should be eaten on there own. We could at this point get into Oxidative Stress caused by foods and hard exercise. but that is another story.

  • mark

    hi. i have a very basic question. should i drink a smoothie every morning? it seems that some fruits behave just fine when blended, but others don’t. also, dr. greger mentions that whole grains that are blended/powdered are not as healthy as eating the whole grain. i do like to throw grains, seeds and nuts into my smoothies. am i just safer eating the fruits, veggies, grains, etc, as opposed to blending them?

  • ron

    Dr. C. Esselstyn on his website under FAQ say’s this: “Avoid smoothies. When the fiber is pureed, it is not chewed and does not have the opportunity to mix with the facultative anaerobic bacteria which reside in the crypts and grooves or our tongue. These bacteria are capable of reducing the nitrates in green leafy vegetables to nitrites in the mouth. When the nitrites are swallowed, they are further reduced by gastric acid to nitric oxide which may now enter the nitric oxide pool. Furthermore, when chewing fruit the fructose is bound to fiber and absorption is safe and slow. On the other hand, when fruit is blenderized, the fructose is separated from the fiber and the absorption is very rapid through the stomach. This rapid absorption tends to injure the liver, glycates protein and injures the endothelial cells.”

    This is beyond me and my understanding. I am shocked as I have been having a breakfast smoothies every morning for 3 years and I never felt better. I lost 20 pounds the first year and I am 82, 155 Lb. and 5ft 7in. I had a triple bypass 15 years ago. My activity is limited as I also have osteo arthritis. I had 2 hip replacements 13+14 years ago .My attention to nutrition is important and about 90% plant based now. I’m sad about Dr. Esselstyns comment.

  • nmarsha11


    I would firstly like to thank you for the incredible knowledge base you and your team have created and shared with the world through It is a life changing resource!

    A few years ago I had a number of health problems, which lead me down a long path that ended with a committment to consuming a 100% plant-based diet. Because of my busy schedule I have been taking a green plant-based supplement in powder form. Obviously the modern ‘fast food’ diet is (generally speaking) highly processed and laden with toxic chemicals so any plant-based supplement is going likely to have some benefit. I certainly feel great, have a ton of energy and basically haven’t been sick since I started taking it. I have attached the ingredients panel below.

    From a scientific perspective and not disregarding the fact that there is no single ‘best’ diet for everyone – what is the general bioavailability of something like this and would you recommend consuming it? It boasts having over 70 vital ingredients.

    Any feedback you might have is very much appreciated.

    • Glad to hear that you’ve improved so much!

      Can you provide any further details and are these supplements?

  • Nick Marshall

    Also, what in your opinion is the best form of plant based protein isolate? There are many on the market including protein from golden peas, rice, etc. I have been trying to put on weight at the gym but find it difficult to consume the required calories to do so.

  • No worries Nick, I think you’ve answer the question yourself! Whole foods the 1st choice as always (except in the case of B12 and perhaps microalgae oil & Vitamin D). From a personal perspective, I’m always careful about the megadoses of vitamins and minerals companies add as you might know, when consumed in excess in the long term, they can potentially have an adverse effect on health (eg. Vitamin A). The other point is, if you are eating a healthy plant based diet, you shouldn’t require these types of supplements as you are covered for all nutrients.

    A typical example of how it works is shown in the video below:

    Broccoli: Sprouts vs. Supplements

    Hope this answer helps.

  • chefmegantucker

    Hi Dr Greger,
    I’ve been vegan or the last four years, have read your book and eat a mostly whole foods. I avoid oil, processed sugar and flour, and very rarely drink alcohol. I love vegetables, fruit and legumes and cook a lot at home, but also travel a lot for work. I’ve been seeing a hormone specialist for the last year. Six months ago I was diagnosed with adrenal fatigue, vitamin D and B12 deficiencies, and borderline anemia. All of my hormones were out of balance: estrogen high, testosterone high, progesterone low and cortisol high (and high at the wrong times of day). I was told to reduce my stress, eat more vegetables, legumes, fat, probiotic foods, and omit grains and all processed foods, caffeine and alcohol, in addition to taking a bunch of supplements. I recently had a follow up after retesting and there is some improvement. The D is in normal range, the hormones are better but still need to improve. I am going to have some testing to see if I have a gut infection. I am having symptoms of hypoglycemia and she is suggesting many small meals throughout the day. Any recommendations and specifically, should I avoid grains?