Doctor's Note

If those citrus phytonutrients sounded familiar to you, it’s because I mentioned them before in videos like Keeping Your Hands Warm With Citrus and Reducing Muscle Fatigue With Citrus. It’s still better to eat the whole fruit though (See Best Fruit Juice and Apple Juice May Be Worse Than Sugar Water).

Digestion isn’t the only physiological source of free radicals—exercise is too. See Preventing Exercise-Induced Oxidative Stress With Watercress.

Background on the role free radicals play in aging and disease can be found in my video Mitochondrial Theory of Aging. Antioxidant-rich diets can even change gene expression: Plant-Based Diets and Cellular Stress Defenses.

Is there a refined sweetener that doesn’t cause free radical formation? Yes: Erythritol May Be a Sweet Antioxidant.

What’s the best way of reaching our daily minimum of 8-11,000 antioxidant units a day? So glad you asked! Covered in my next video, How to Reach the Antioxidant RDA.

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  • Annie L

    Can anyone please help moi understand why one might be having IBS issues while eating foods high in sucrose: sweet potatoes, bananas, apples, corn chips, brown rice and much more. Some of these foods don’t have a lot of “sugar” in them but when you look up the “sucrose” content it is very high. Fructose does not seem to bother me near as much. Is there some kind of chemical in sucrose that can cause issues? 1/2 cup of artichokes has more sucrose than a cup of red grapes. One cup of carrots has 4,600 mg of sucrose and one cup of raspberries has 264 mg. Makes no sense but these are the numbers and I don’t do well on high-sucrose foods.

    Maybe someone here that understands sugar chemicals can make sense of this for me. It has been a struggle on plant-based, because of this, and I have been vegan for many years.

    • Betty

      I had problems with IBS until I got rid of processed foods. Perhaps you should dump the corn chips and what ever else you’re eating that comes in a package.

      • Alan

        Yes, get rid of the corn chips. I used to drink a fair amount of alcohol and i also ate a lot of corn chips and potato chips. My stomach was bothering me and getting worse.Not wanting to give up the alcohol i gave up the chips first and my stomach problems went away. Just for the record i have given up alcohol since then. Praise the Lord !!!

      • Annie L

        Ironically, it is mostly the raw, fresh, and “healthy” fruits and vegetables that cause me the most issues. Mangoes, apples, carrots, artichokes, pineapple – the ones highest in sucrose. I only eat corn chips once every 2 weeks or so. Sucrose metabolism might be an issue for some people, even with fresh unprocessed foods.

        • Coacervate

          I have a close friend with the same problem. We just could not understand why but the determination was there. He was successful by very slowly adding fruits and veg to his eating pattern. I can tell you it took some months but he is now eating whole foods, plant based. Good luck.

          • Annie L

            Thank you for sharing this. There are fruits and veggies low in “sucrose” that do not cause me as much issue. Oh well, so it is.

          • Veganrunner

            Have you looked into how much fiber you are eating? I find on the days with 80 grams or more I have an issue. And until I put my foods into a app I had no idea I was eating that much.

          • Coacervate

            Yes, same for me too. Good point.

          • Annie L

            I find it difficult to be a vegan and not get tons of fiber, yet still get enough calories. How can one get enough plant based calories yet limit fiber? Drinking fruit juice is not the answer for me, nor is high-fat plant foods.

          • Veganrunner

            I try and not go crazy with my morning smoothy and keep it a reasonable size. 30-40 oz causes a bad couple of days. If I keep to below 20 I am ok. Also I don’t do them daily anymore. My stomach just works better that way. I rotate oatmeal. I played with the FODMAPs but it didn’t make a difference. I don’t drink juice. I also do better with starchy veggies.

          • Anthony Gonsalves

            So wait, you don’t want the fiber? Let me answer the calories first because i’m not sure what you meant by that. Nuts, seeds, cooked beans, vegetable oils, rice (wild rice (techincally a seed), japonica, brown rice and sushi rice are only ones I eat) will all give you good caloric content. It’s really easy to get enough calories, just not as concentrated like tissue (meat).

          • desertpooch

            How much soy are you eating? I find it is the worst of the bunch in foods and it is in almost everything you buy at the store. Do some research on Soy and I think that you will find it is the culprit.

          • Annie L

            I never eat soy. Not a GI issue for me, the soy, but soy is not something I would put on my plate.

        • Steve S


        • David

          If you know that certain foods give you issues, then why do you continue to put them in your mouth?
          And, if you’ve been vegan for many years, why haven’t you noticed sugar issues sooner?
          There is Dr Rhonda Patrick who’s does research on human longevity. She has a YouTube channel as FoundMyFitness
          She has a video where she interviews two other doctors who are doing research on the microbiome in the gut.
          Search: How the gut microbiota affects our health with dr erica and dr justin sonnenburg
          It’s been noted that the microbes in the lower intestinal track use fiber as their food staple.
          If your diet is lacking in fiber, then as these microbes die they do not protect the lining of the intestine as well, which eventually leads to leaky gut. Before leaky gut happens there is much inflammation and immune system issues, which has symptoms diagnosed as IBS or Chron’s.
          I personally don’t eat much fruit because of the digestive issues fruit causes me.
          I’ve been understanding IBS from an inflammation/immune system response rather than a disease.
          So I’ve modified my diet in a way which better supports my immune system and the microbiome in my gut.

          • Annie L

            I eat too much fiber, plant fiber, that is. At least this is what i think one of the issues might be. Beans, raw veggies, cooked veggies, nothing processed or junk. Nuts and seeds, organic, no oils. Fresh raw fruit. Clean water. No gluten. I eat some brown rice, corn.

            FODMAPS and fruit digestion, i think, is the issue. Or, a issue. It is difficult to give up fruit (tastes good).

            B12 also messes up my body, all forms of B12 in supplement, even the purest ones.

            May try fermented foods, your thoughts?

          • Rich

            Can you eat too much fibre?

    • Steve Billig

      Annie, your data on sucrose is correct, but your interpretation of what it means is off. Yes, 1/2 cup of artichokes has more sucrose than one cup of grapes, but both have minuscule amounts, less than 1/4 teaspoon, as does 1 cup of raspberries. And a cup of raw carrots has about 1 teaspoon of sugar, as does a cup of sweet potatoes. In general, you should not worry about sucrose,or sugars in general in whole foods, including fruit.

    • JoAnn Downey

      I’m not exactly replying, because I too have a sucrose question. Sucrose is a disaccharide made up of glucose and fructose. So for complete digestion, that sucrose molecule would have to be broken down into two monosaccharides: glucose and fructose. I’m confused how we would know if it was the glucose or the fructose causing a problem? Re the IBS: ditch any processed food including corn chips and see what happens.

      • Annie L

        JoAnn, thanks for the question. I go to and type in the various foods that seem to cause me a bit of problems. What these foods have in common is a high sucrose content. You can click on the “carbs” tab for each food item, and the section will open up to reveal each sugar content : fructose, glucose, sucrose, etc.

        Is this just a random thing for me? I don’t know. But my experience is fairly consistent and interesting.

    • Nate Porter

      I thought it was sugars at first with my stomach issues, even going vegan didn’t eliminate problems. Eventually I pinned it to fat intake. If there’s oils in things I eat or something is too fatty like chips I have stomach problems. I can’t tolerate nuts either, they cause me bad stomach pain, but seeds are fine. Try going low fat, if thats an factor. Just my experience but I offer it in case it helps.

    • Jeanne

      It doesn’t exactly answer the question you are asking, but kiwi fruit is supposed to be good for IBS. You might consider doing a little research and then including them in your diet. I like to peel them, slice and then freeze to include a few slices in my smoothies. Buy organic when possible.

    • IBS is a nonspecific description of GI symptoms that can have many causes. Sucrose is a disaccharide composed of one molecule of glucose and one molecule of fructose. Sucrose is broken down by an enzyme, sucrase, in the small intestine. Brown rice is very low in “sugar” but high in starches which are essentially long chains of glucose molecules. Sweet potatoes are somewhat higher in sugars but still have 4X as much starch. You can use the website, Cronometer, to check the various contents. Since it is complex and difficult to understand you have to go with what works. I would avoid high sucrose foods but check the foods so you have accurate information and aren’t “throwing out the baby with the bath water”.

      • Annie L

        Thank you. And I’ll check out cronometer.

  • Mike

    I read in “The McDougall Program for a Healthy Heart,” published in 1996, that too much sugar can raise cholesterol, and so, Dr. McDougall recommends only two servings of fruit a day, or three at most. Is this a good idea, or do the antioxidants and fiber prevent damage from the sugars, allowing us to eat more servings than that?

    • Andy

      Too much fruit intake can indeed raise cholesterol. I believe that it raises your triglycerides. Vegetables have antioxidants too so you can get them there too…

      • I have the privilege of working with Dr. McDougall at the McDougall Whole Foods program which is an 8 day program similar to the McDougall 10-day program. Most patients in my experience can tolerate up to 4 servings of fruit/day. Most participants in the McDougall program see drops in cholesterol in the order of 30% by eating what they want consistent with the whole food plant based diet with no oils. If they still have problems with their cholesterol or triglyceride targets while on the correct diet then limiting fruit intake would be the next step. It is the fructose in fruit and sugar (e.g.50% fructose) that causes the elevation. It is also appears, based on limited scientific studies, to be less of a problem if the intake of fruit is spread out over time. Eating a variety of vegetables and some fruits should give you adequate antioxidants. You will need to work with your physician to come up with the best path for you. Good luck.

  • SillySallySue

    Excellent information, as usual. Thanks! But am I the only one seeing a fuzzy, low quality video? Could someone have uploaded this incorrectly? I can’t read the charts, etc. Thanks in advance.

    • brec

      Looks fine here. The only fuzziness occurs for a few seconds after switching to full-screen, but that’s typical on all sites.

    • I think that’s just a function of the poor quality of the original source material. Some of the old literature is scanned in fuzzy.

  • Bill Misner PhD

    Brilliant and so true…to the point….Dang wish I had said this! Well done Dr. Greger.

  • Kjell Ottesen

    This video is absolutely awesome! I have followed recommendations from Dr. Greger and also from Forks over Knives and it have changed my life to the better. Blood pressure is 112/72 and I am off Statins which totally surprised my GP (Most GPs unfortunately have limited knowledge of antioxidants and free radical damage) My antioxidant levels are scanned every four weeks and as long as I can maintain my high AO score, I am less likely to get any illnesses and diseases as Dr. Greger mention in this video! Thanks for this wonderful web page and videos!!

    • Carlyle070

      Can you share what kind of test is it that checks for antioxidant content? Is it a standard test? How do you get it done?
      Thank you

      • Kjell Ottesen

        I will be happy to see if there is a scanner operator in your area. Please email me your zip code to, and I will let you know what I can find!

  • thanks, very clear information

  • fstfingers

    Thank you for this video and transcript that informs us how antioxidants work and how many millimoles we need to eat each day, but how does that translate into servings of food? I think I missed that part or didn’t understand. How many oranges do I need to eat? Or cups of strawberries? Is there a table or graph somewhere that has this information? If I need to eat 8,000 millimoles to break even, how do I get it?

  • Steve Weinberg

    Can a person get too many antioxidants and would it be harmful?

  • Brandon Klinedinst

    I got a “404 Page not found” when trying to view “How to Reach the Antioxidant RDA”

  • Darryl

    The mechanism of dietary “antioxidants” is a bit more complicated. Absorption of dietary antioxidants is too low (excepting vitamin E in lipid membranes), and their reaction rates are too slow, to account for any quenching of reactive species in vivo. See How do nutritional antioxidants really work: Nucleophilic tone and para-hormesis versus free radical scavenging in vivo, or the presentation by author Fulvio Ursini, who has worked in free radical and oxidation research for 35 years.

    Dietary compounds that act as test-tube “antioxidants” generally have labile structures that act as redox cyclers in vivo. For example, cancer cells in culture can be killed by reactive oxygen species generated by green tea polyphenols. So how do low doses of these compounds reduce oxidative stress? There’s a large body of evidence that they act via pro-oxidant modifications of proteins that regulate stress responses, for example the Keap1/Nrf2 regulated endogenous antioxidants, or NF-κB regulated inflammatory responses.

    In light of the latter and this video, another recent paper of considerable interest was There is no evidence that mitochondria are the main source of reactive oxygen species in mammalian cells, which reviews evidence that our energy-converting organelles, contrary to decades of widespread assumption, are not the major source of reactive species. It appears that two enzymes in inflammatory responses, NADPH oxidase and xanthine oxidase, found in macrophage phagosomes, activated microglia peroxisomes, and serum, may be the major sources of oxidative stress. Many dietary phytochemicals inhibit NF-κB and hence inflammatory responses, some, like our friend phytate, inhibit oxidases directly.

    The scientific consensus on how dietary antioxidants function in vivo has changed markedly in the past decade, Turns out that its far more complicated than quenching trolox in a test tube.

    • VegAtHeart

      I just went through your post and Ursin’s presentation with great interest. I wish I could say I understand what is being said, but I unfortunately am no chemist.

      I probably misunderstood, but I came away with the impression that that polyphenols produce their beneficial health effects by mimicking pro-oxidants and that this stimulates an endogenous anti-oxidant response that is helpful. Terms like nucleophilic displacement reactions were confusing to me. But I must be misunderstanding, because I don’t get why this is hormetic (or para-hormetic, to use Ursin’s term); where does the J shaped curve come from?
      Time permitting, it would be useful if someone could provide us with a simple example to illustrate the typical process whereby antioxidants produce their effects — without too much jargon (i.e. kitchen table explanation) please! Say one consumes one specific polyphenol from green tea. How will it produce a beneficial effect?
      Anyway, thank you for a very thought-provoking post.

      • Darryl

        I’ll probably oversimplify, but chemical potential energy is lower when every atom has complete outer electron shell. An oxidant is a compound that can achieve a lower energy state, and hence “wants”, to take an electron or hydrogen from others. Hence the term electrophile. Singlet oxygen wants two hydrogens to become water, and that reaction releases enough energy to launch rockets. Free radicals, which have an unpaired electrons, have very low activation energies to overcome, and are hence extremely reactive oxidants.

        An antioxidant is simply a compound that can easily give up a electron or hydrogen. Polyphenols have their electron charge distributed over an aromatic ring, and hence their potential energy doesn’t rise so much after loss of a hydrogen from one of their hydroxyl groups. In donating a hydrogen to a free radicals, the energy of the polyphenol increases a little, but that of the oxidant decreases dramatically, which means the net effect is much lower net energy.

        Endogenous antioxidants like glutathione use cellular energy to contantly recycle into their reduced (antioxidant) state. Some dietary antioxidants like vitamin C are recycled as well (though levels are restricted to limit reduction of redox active Fe & Cu). But what happens to a polyphenol like tea EGCG after its given up a couple hydrogens? It becomes a quinone, with a couple doubly bonded oxygens in place of its hydroxyl groups, which is itself an electrophile. Here’s where it gets interesting. Quinones are reactive with sulfhydryl groups, like those of cysteines that cells use to detect electrophiles (in signalling, and redox homeostasis). One of these is Keap1, a protein that holds the transcription factor Nrf2 in the cytoplasm.

        The disrupted cysteines change the conformation of Keap1, releasing Nrf2 to enter the nucleus and initiate transcription of hundreds of cytoprotective genes, including those for glutathione synthesis & recycling and other endogenous antioxidant enzymes.

        This explains how small concentrations of EGCG and other dietary “antioxidants”, once oxidized, react in prooxidant fashion to induce endogenous antioxidant responses. The endogenous antioxidants are orders of magnitude more potent than EGCGs own contribution. Moreover, it also accounts for why high, non-physiological concentrations of EGCG and other polyphenols have a prooxidant effect. It cycles between reduced (phenol, nucleophile) and oxidized (quinone, electrophile) forms, overwhelming the capacity of endogeneous glutathione to keep it in a reduced state.

        My last chemistry class was 20 years ago, and covered none of this, so I’d very much appreciate it if any experts could critique my understanding.

    • Darryl,

      If I could be so bold as to attempt to really simplify what you’re saying here, is the following paraphrase correct? And if it’s not, would you be so kind as to edit it?

      “Anti-oxidant activity may be too simple a description of how compounds in plants exert beneficial health effects. The ability of plant nutrients to inhibit a compound called nuclear factor-kappa B (NF- kB) may be more important than their ability simply to scavenge free radicals. NF-kB helps cancer cells hide from the immune system and promotes the expression of cancer-promoting genes.”

      Darryl, do free radicals of oxygen trigger our bodies to produce NF-kB? Could you explain that? I may be totally misunderstanding you.

      • Darryl

        Not quite.

        NF-kB is a “information integrator”, a signalling hub between inflammatory stimuli and responses. Its absolutely necessary for immune response to infection and wound healing. For example, the redness around a wound is due to inflammatory action (vasodilation, angiogenesis, white blood cells engulfing pathogens).

        Cancer cells can benefit from chronic inflammation as it encourages angiogenesis of new blood vessels throughout the tumor. Here is a small collection of papers on the roles of NF-kB in cancer.

        Inflammation, incidentally, is the major source of free radicals in multiple disease states. The very same enzymes responsible for digesting pathogens in inflammatory response (like NADPH oxidase/NOX and xanthine oxidase) can become overactive in chronic inflammation. Overactive NOX, for example, is suspect in:

        Atherosclerosis / Hypertension / Cardiac Hypertrophy / Congestive Heart Failure / Aortic Aneurysms / Sleep Apnea / Tissue Damage stemming from Heart Attack or Stroke / Insulin Resistance Syndrome / Major Complications of Diabetes, including Kidney Failure, Blindness, and Heart Disease / Erectile Dysfunction / Cartilage Loss in Osteoarthritis and Rheumatoid Arthritis / Osteoporosis / Inflammatory Carcinogenesis / Alzheimer’s Disease / Parkinson’s Disease / Liver Cirrhosis associated with Hepatitis or Alcoholism / Sun-Induced Skin Damage and Sunburn / Pulmonary Fibrosis / Periodontal Disease / Pre-eclampsia / Asthma / Allergies / Septic Shock / Scleroderma / Glaucoma-induced Blindness / Sickle Cell Anemia

        The overwhelming majority of free radicals our bodies are exposed to are produced endogenously, primarily by inflammatory superoxide generating enzymes like NOX and in normal mitochondrial metabolism. Environmental exposures are small by comparison. As we grow older, more of our cells become senescent through the actions of p53 and other tumor suppressors, and for reasons not entirely understood, senescent cells produce more inflammatory cytokines (IL-1, IL-6 etc) upstream of NF-kB, resulting in chronic inflammation, overactive NOX, etc.

        Many, many plant phytochemicals inhibit NF-kB activity, but not necessarily because they are functioning as direct antioxidants. There are other “information hubs” that respond to different kind of stress (Nrf2=oxidative stress, AMPK=energy shortages), that when activated, also happen to suppress NF-kB activity, often through complex negative feedback mechanisms.

        Its a really fascinating tangle of wires down there on the switchboards. No person well ever have a complete knowledge of the network, but the regulatory hubs are fewer and more comprehensible. Less than a dozen, including NF-kB, Nrf2, AMPK, mTOR, Sirt1, PPAR etc. pop up repeatedly in the past decade’s literature on nutrition and disease prevention at the cellular level. In a few decades, some of these will be as familiar as “spleen” or “pancreas”, at least to those who want to know why some diets prevent disease…

        • Are you referring to the 12 or so signalling pathways that regulate cell fate, cell survival and maintenance of the genome?

          • Darryl

            Neat paper, which I plan to read. From skimming the 12 proteins listed in that paper deal more specifically with carcinogenesis, but some of those 12 oncogenes, like PI3K (upstream of mTOR) or STAT (downstream of NF-kB and mTOR) are closely related to the hubs I’ve been reading about. Various scientific communities can talk about much the same nexus or pathways with different labels. In the tiny (by comparison) gerontology community mTOR reigns, but oncologists may prefer to talk about PI3K.

            To get an idea of why NF-kB and similar transcriptional regulatory hubs are so interesting as dietary intervention targets, consider this depiction of cell signalling pathways leading through it. Its like Grand Central Station.

          • Have you read that paper? Any more enlightening comments? (All your comments are enlightening!) Speaking of which, I recall you speculated somewhere that vegans should perhaps aim for a certain amino acid profile–perhaps low methionine and something else? Could you repeat that thought please?

          • Darryl

            There’s speculation in the literature that some of the health benefits of vegan diets arise from their lower quanties of methionine and leucine.
            Cancer cell proliferation is methionine-dependant, and excess methionine may contribute to both elevated homocysteine and mitochondrial oxidative stress. Excess leucine rather directly activates mTORC1, the intracellular anabolism/catabolism regulatory hub, increasing protein synthesis and reducing autophagy. As every successful anti-aging intervention in mammals (caloric / protein / methionine restriction, rapamycin, metformin, NGDA, aspirin(!), etc) inhibits mTORC1 and induces autophagy, it stands to reason that moderating leucine stimulation may also be a benefit of vegan diets.

            Methionine moderation in vegan diets is rather easy, as vegan proteins are on average about 1.4% methionine, while animal proteins are 2.6%, and many vegan proteins have high glycine / methionine ratios (which may reduce excess free methionine in cells). One can still tally up a high vegan methionine intake if soy protein isolates and some other higher protein foods represent a big part of one’s calories. Oats and peas are especially attractive as low methionine foods with higher glycine content. I’d guestimate most whole plant based diet would be around 150-250% of the ~0.7 g methionine requirement, whereas most omnivore diets are 3-600%.

            The difference in leucine content is not as great between plant (5-8%) and animal flesh (7-8%), but significantly lower than dairy (10%) or eggs (9%). Its very difficult to restrict leucine content in a varied whole plant based diet, but the more moderate protein intake and absence of dairy and eggs would result in intakes of 2-300% of the ~2.7 g requirement, vs. (again) 3-600 in omnivore diets.

            The main amino acid for most vegans to pay attention to is lysine, which many plant proteins are deficient in. A couple servings of legumes (in the context of an otherwise varied diet) can ensure lysine sufficiency, but a very high-legume diet would also raise methionine and leucine to omnivore intakes.

            Right now, determining an optimum protein intake is pretty speculative, as there are positives for leucine too: mTORC1 activation functions in the hypothalamus to satiety (and aid dieting), in muscles to increase muscular growth, etc. For longevity and chronic disease risk reduction, though, it looks like moderation in overall protein intake, at least till age 65-70, may be a winning strategy. For the elderly, more mTORC1 activation may be desired to keep weight up. See:

            Levine, Morgan E., et al. “Low protein intake is associated with a major reduction in IGF-1, cancer, and overall mortality in the 65 and younger but not older population.” Cell metabolism 19.3 (2014): 407-417.

          • Just wondering if you’ve read that paper and if you have any more insights re: the signalling pathways discussed therein? No rush.

  • GC

    Wow! Eat veggies or die!

    • Julot

      Eat fruits even more!

    • Loay

      I agree! no need for the scare tactics! let the data speak for itself.

  • ldm

    So I am trying to compare this video (which states 8 to 11K millimoles of Trolox equivalents is the needed minimum intake to keep up with the oxidation caused just by digestion) with the better breakfast video which shows Dr Greger’s smoothie having a total of 1558 total but am not able to clearly read the units of measurement (10 to the negative 1 millimoles? is that correct?). He says he gets more in his one smoothie than the average person gets in an entire week (which according to this video is less than 5K millimoles of Trolox equivalents). I want to calculate how much of the recommended 8 to 11K is the blueberry/alma powder smoothie supplying.
    Can someone shed light on the units of measurement so I can compare apples to oranges so to speak. Thanks!

  • BreAnna Waliser N.D.

    Michael Greger, you are my hero! hope to meet you someday!

  • dawn

    This information is only helpful if we’re given some clue about how many antioxidants there are in fruits/veggies. Last i checked, antioxidant levels are not listed on the ingredients labels so i imagine no one has a clue?

  • Zhalfrin

    Where do cooked wholegrains (brown rice, oats etc.) and beans/legumes lie on the antioxidant scale?

  • joep m

    Hi Mike, the link to the ‘how to get to the recommended RDA’ does not seem to be working, can you check the url?

    • Won’t go live until the video does tomorrow at 8am–sorry for the confusion!

  • Andy

    the How to Reach the Antioxidant RDA. link doesnt work!

  • Ross

    My wife works out 2 hours per day and has been doing wonderfully on the 100% Vegan for about a year and her health has improved along with her blood numbers. With my energy levels low would there be foods you might suggest I get back into to repair what you outlined as missing (heme iron, taurine, CoQ10, not to mention cholesterol, saturated fat, and protein generally) in your email? I would appreciate it. I’m thinking olive oil or fish(oil) fresh from the sea or sardines? Your book is very interesting so far and again thanks for sending it. FYI, just for interest sake this is what I eat each day:

    Everyday starts
    1 Quart of Lemon Water (this has appeared to be very helpful to me)

    6 various fruits per day
    Oatmeal(real oats) with Chia/Millett/Flax/raisins/drop of MS or Agave/ goji berries, hemp hearts(have this about 3-4X’s per week(weekends flax bread with PB&J)

    3 pounds of salad made up of broccoli, cauliflower, red cabbage, red pepper, snow peas, carrots, tomatoes, quinoa, red onion and a drop of homemade dressing(olive oil/lemon)
    or large homemade mushroom or other vege soup

    Cooked various vegan cookbook fair with lots of veges

    Homemade ginger cookies or banana bread or fruit

    I figure if you saw what I eat maybe you would have some quick suggestions about ‘what foods’ I’m missing. I sincerely appreciate your thoughts as this is becoming quite frustrating when I have ALWAYS been perfectly healthy and although I only workout 30 minutes per day, have always had stamina!

    PS: For the past 8 years our meals have been similar except we ate ‘fresh from the sea’ no processed varieties of NS fish 4 nites per week.

    Happy New Year. Ross

  • Kaleb Rogers

    Dr. Greger — The majority of your videos covering antioxidant research seem to focus on the quantity of antioxidants rather than the quality. Hibiscus has more antioxidants than matcha, amla has more antioxidants than blueberries, etc. However, I find myself wondering if all antioxidants are created equal. I would love to see a sort of ‘one stop’ video comparing the unique benefits of different antioxidants. I am assuming that a diet rich in a variety of antioxidants would be superior to one saturated with EGCG but lacking in others.

    • Thea

      Kaleb: I can’t answer for Dr. Greger, but I have a thought for you. Dr. Greger does seem to have several videos that argue against taking *any* single anti-oxidant. Even vitamin C by itself may do more harm than good. But foods like oranges and broccoli with not only vitamin C, but a bazillion other antioxidants consistently show themselves as being good for us.

      Thus, I would argue that Dr. Greger has already addressed your interest. In other words, based on my understanding, Dr. Greger wouldn’t want to have a video that argues for one particular antioxidant over others because that would go against the main message that focusing on whole plant foods provides the most and safest benefits — especially focusing on those whole plant foods that consistently show large benefits in studies (for example, berries and dark leafy greens).

      Rather than looking at specific antioxidants, a more interesting question to me would be looking at whether our bodies absorb or benefit from those antioxidants more or less with some whole foods vs others. I think he has addressed this in one or more videos, but I’m not able to think of a specific one just at this moment.

      Anyway, that’s just my thought on the topic. Good luck to you.

      • Kaleb Rogers

        I understand that whole foods are superior to isolated nutrients. However, one cannot argue that oranges provide a vast supply of vitamin C. Likewise, green tea provides a hefty supply of EGCG. I think it would be nice to show a comparison of different antioxidants from whole food sources, of course.

        • Joe

          I am also interested in this. I drink green tea and hibiscus regularly. Supposedly, Hibiscus has more antioxidants, but the antioxidants are different and must differ slightly. Strength would be one interesting comparison. Time active in the body would be another, as well as absorption.

          I guess it comes down to whether we see antioxidants as simply units of free radical neutralizers, or we look into their other functions too. For example, Vitamin C is not as strong as others, but it performs essential other tasks, like connective tissue formation.

  • I like the prepackaging of sugar which is why a whole food diet is very important.

  • Bruce

    Ok, so I need 11,000 units of phyto nutrients. How does that translate into the food I eat? How many apples or blueberries do I nee to eat?

  • lma44

    Recently the USDA’s Nutrient Data Laboratory (NDL) removed the USDA ORAC Database for Selected Foods from the NDL website due to mounting evidence that the values indicating antioxidant capacity have no relevance to the effects of specific bioactive compounds, including polyphenols on human health.

    There are a number of bioactive compounds which are theorized to have a role in preventing or ameliorating various chronic diseases such as cancer, coronary vascular disease, Alzheimer’s, and diabetes. However, the associated metabolic pathways are not completely understood and non-antioxidant mechanisms, still undefined, may be responsible. ORAC values are routinely misused by food and dietary supplement manufacturing companies to promote their products and by consumers to guide their food and dietary supplement choices.

    A number of chemical techniques, of which Oxygen Radical Absorbance Capacity (ORAC) is, one, were developed in an attempt to measure the antioxidant capacity of foods. The ORAC assay measures the degree of inhibition of peroxy-radical-induced oxidation by the compounds of interest in a chemical milieu. It measures the value as Trolox equivalents and includes both inhibition time and the extent of inhibition of oxidation. Some newer versions of the ORAC assay use other substrates and results among the various ORAC assays are not comparable. In addition to the ORAC assay, other measures of antioxidant capacity include ferric ion reducing antioxidant power (FRAP) and trolox equivalence antioxidant capacity (TEAC) assays. These assays are based on discrete underlying mechanisms that use different radical or oxidant sources and therefore generate distinct values and cannot be compared directly.

    There is no evidence that the beneficial effects of polyphenol-rich foods can be attributed to the antioxidant properties of these foods. The data for antioxidant capacity of foods generated by in vitro (test-tube) methods cannot be extrapolated to in vivo (human) effects and the clinical trials to test benefits of dietary antioxidants have produced mixed results. We know now that antioxidant molecules in food have a wide range of functions, many of which are unrelated to the ability to absorb free radicals.

  • Ben Pearson

    Hiya – is there any evidence that shows that an anti-oxidant rich diet has a marked increase in health/average lifespan. If so, what is the best quality of evidence available at the moment. I.e. is there a systematic review of randomised double blind trials? Or is the best available evidence still found in in vitro studies?
    Many thanks

  • Hi, I’ve recently decided to go vegan after watching your videos – thank you for such a great website! I’ve also seen the research on vitamin supplements, but I would like to know if the same applies to powder-based superfoods? I try to eat as varied diet as possible but noticed after I stopped taking Nutrilite’s Double X (a highly concentrated multivitamin, multimineral, phytonutrient supplement supposedly from plant based material) – that my mood and energy slipped back. I was hoping to get this energy lift back by adding something like Vital Greens Phytonutrient Superfood – but not sure if that’s essentially the same as taking harmful vitamin pills? Thanks..

  • Cess

    Hello, what’s the basis of 8-11,000 antioxidant units a day?

  • Is this minimum requirement for everybody as a baseline? Or would it be different for plant based eaters without dairy, meat, or milk in their diet? Wouldn’t we have a lower oxidative debt?

  • gr

    Any way we can log how many antioxidants we are getting each day? I think in coming up short in calories and antioxidants.

    • Joan E, RD-NF Volunteer

      There is an ORAC score that foods have, it is the Oxygen Radical Absorbance Capacity that looks at the overall antioxidant effect of food. You can get a comprehensive list here Otherwise, to keep it simple, I would direct you to Dr. Gregers Daily Dozen app. If you include the servings of the foods he recommends, you are very likely to be consuming abundant amounts of antioxidants.