How to Get Enough Antioxidants Each Day

Image Credit: Mr.TinDC / Flickr. This image has been modified.

How to Get Enough Antioxidants Each Day

We need to get a daily minimum of 8-11,000 antioxidant units a day in our food just to stay out of oxidative debt (see my video on How to Reach the Antioxidant “RDA”). To reach that minimum, all we have to do is eat lots of fruits and vegetables, right? Not exactly. Let’s say I ate a whole banana during breakfast (in addition to whatever else). For lunch I eat a typical American salad— iceberg lettuce, half cup of cucumber slices, and canned peaches for dessert. Supper included a side serving of peas and carrots and half a cup of snap peas along with yet another salad. And, finally, let’s say I had a cup of watermelon for dessert. I just ate nine servings of fruits and vegetables and am feeling all good about myself. However, I only made it up to 2700 units, less than a quarter of the way to my minimum daily recommended intake. What am I supposed to do, eat 36 servings a day? (For a cool visual of this, check out my video, How to Reach the Antioxidant “RDA”).

What if instead of that banana, I had a single serving of blueberries? And instead of iceberg lettuce for that afternoon salad, I ate four leaves of red leaf lettuce, maybe some kidney beans on top, and a teaspoon of dried oregano as a bonus? For a snack, I had an apple and some dates. It’s not even suppertime, only had five servings, yet I’ve left the minimum recommended daily intake of antioxidants in the dust (topping 28,000 units!). That’s why it’s not just quantity of fruits and veggies that matters, but also the quality. All fruits and veggies aren’t the same. I make this point in different ways in videos like Which Fruit Fights Cancer Better? and Anti-Inflammatory Antioxidants. If possible, we should try to choose the healthiest options out there.

Now that it’s midday and I’ve reached my daily minimum of antioxidants with those five super servings, can I just eat whatever I want for dinner? That’s probably not a good idea. The estimated minimum antioxidant need of 8,000-11,000 units does not take into account the added amounts needed if other oxidant stressors—”such as illness, cigarette smoke, meat consumption, air pollution, sleep deprivation”—are present. If we had to deal with these stressors we’d need to consume more fruits and veggies just to stay out of the red.

In my video Antioxidant Level Dynamics, I profiled a study that used an argon laser to measure human antioxidant levels in real time. The study’s most important finding was that antioxidant levels can plummet within two hours of a stressful event, but it may take up to three days to get our levels back to normal. The take-home message is that, especially when we’re sick, stressed, or tired, we should try to go above and beyond the antioxidant food minimum. Ideally, we need to be constantly soaking our bloodstream with antioxidants, meaning that we should consume high-powered fruits and vegetables—like berries, beans, and green tea or hibiscus—all day long.

Unsure of which foods have the most antioxidants? I have a series of videos on this very topic. See Antioxidant Content of 3,139 Foods and Antioxidant Power of Plant Foods Versus Animal Foods. (Note these are measured based on test tube tests. There are more sophisticated ways to measure antioxidant activity. See Anti Up on the Veggies). Spices in particular present a powerful source of antioxidants. See Antioxidants in a Pinch.

What’s the cheapest common source of whole food antioxidants? See Superfood Bargains for a dollar per dollar comparison. What’s the cheapest uncommon source? See Dragon’s Blood.

Are there diminishing returns to getting too many antioxidants? See Maxing Out on Antioxidants. So if we have that bowl of berries in the morning to meet our minimum daily antioxidant needs can we just call it a day? See: Antioxidant Rich Foods With Every Meal.

-Michael Greger, M.D.

PS: If you haven’t yet, you can subscribe to my videos for free by clicking here and watch my full 2012 – 2015 presentations Uprooting the Leading Causes of Death, More than an Apple a Day, From Table to Able, and Food as Medicine.


Michael Greger M.D., FACLM

Michael Greger, M.D. FACLM, is a physician, New York Times bestselling author, and internationally recognized professional speaker on a number of important public health issues. Dr. Greger has lectured at the Conference on World Affairs, the National Institutes of Health, and the International Bird Flu Summit, testified before Congress, appeared on The Dr. Oz Show and The Colbert Report, and was invited as an expert witness in defense of Oprah Winfrey at the infamous "meat defamation" trial.

19 responses to “How to Get Enough Antioxidants Each Day

Comment Etiquette

On, you'll find a vibrant community of nutrition enthusiasts, health professionals, and many knowledgeable users seeking to discover the healthiest diet to eat for themselves and their families. As always, our goal is to foster conversations that are insightful, engaging, and most of all, helpful – from the nutrition beginners to the experts in our community.

To do this we need your help, so here are some basic guidelines to get you started.

The Short List

To help maintain and foster a welcoming atmosphere in our comments, please refrain from rude comments, name-calling, and responding to posts that break the rules (see our full Community Guidelines for more details). We will remove any posts in violation of our rules when we see it, which will, unfortunately, include any nicer comments that may have been made in response.

Be respectful and help out our staff and volunteer health supporters by actively not replying to comments that are breaking the rules. Instead, please flag or report them by submitting a ticket to our help desk. is made up of an incredible staff and many dedicated volunteers that work hard to ensure that the comments section runs smoothly and we spend a great deal of time reading comments from our community members.

Have a correction or suggestion for video or blog? Please contact us to let us know. Submitting a correction this way will result in a quicker fix than commenting on a thread with a suggestion or correction.

View the Full Community Guidelines

  1. Another reader of NutritionFacts posted a sobering link to a recent blog post. This link contains a statement published by the USDA in which the USDA casts doubt on the efficacy or importance of antioxidants. The link can be found here:

    If I remember correctly, Dr. Greger has said that the USDA took down its antioxidant database merely because the data was being used unscrupulously by supplement manufacturers to bolster the questionable health claims they generated to market their supplements. However, this USDA statement seems to say something very different. Here are some direct quotations:

    “Recently the USDA’s Nutrient Data Laboratory (NDL) removed the [Antioxidant] Database 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 is no evidence that the beneficial effects of polyphenol-rich foods can be attributed to the antioxidant properties of these foods.”

    (Note that the second statement in particular doesn’t seem to differentiate between the various ways that a food’s antioxidant capacity can be tested.)

    This raises a couple of important questions:

    If we’re not using the USDA’s measure of antioxidant capacity, then what are we using? Where, for instance, do the numbers used in today’s blog post, the antioxidant units of various foods, come from?

    How do we know that the antioxidants in healthy foods are what make those foods healthy in the first place?

    I remember asking myself just this question after watching a video Dr. Greger posted about a study, conducted in Italy I think, in which participants were divided into a high-antioxidant group and a low-antioxidant group. In the study, the high-antioxidant group fared better than the low, and this was presented as strong evidence for the health benefits of high-antioxidant foods. But how do we know it was the antioxidants that did anything? How can we be sure that some other component of the high-antioxidant foods wasn’t responsible for the participants’ increase in health?

    1. Does over reliance and daily consumption of food antioxidants suppress the human body’s own “strength” and abilities? Does the easy access to all this “healthy food” make us actually weaker in the long run, thus making us dependent on fueling our defenses? People have gone long stretch just eating fish, insects,….or fasting…..or whatever to survive. Maybe in the abscence of antioxidants they actually become/became stronger? Have humans ever had this much access to such high antioxidant food, and every single day of the year?

    2. Great read!
      I wanted to provide some research that I use to inform Health Care Professionals about antioxidants and how they can be increased in your body and be scientifically measured. I have a BioPhotonic scanner that can measure the density of the Carotenoid molecules in your skin. When our clients make changes by diet and supplementation, and we measure the increased levels, the clients typically have less colds, infections and inflammations. We have had great success in relieving pain and discomfort with clients with Lyme disease and also other patients with MS, fibromyalgia, arthritis, even periodontal disease. But I just wanted to provide you with a list of research from scientists and universities that might be of interest to you!!scanner-studies/cuns
      (The research references will be on the last, few pages of the PDF)

      Make it a great day!

    3. The concept of ‘antioxidants’ as we have known it has been shown in recent years to be WRONG and was based on flawed arguments which go right back to the 1950s. The current science surrounding the way human cells defend themselves is being completely rewritten. What has emerged is that human cells produce their antioxidant and other protective compounds which are literally capable of dealing with millions of reactive oxygen ans nitrogen species (free radicals) per second. Compare this with one vitamin C molecule which can quench just one free radical – period!

      The clinical trials which have been done in hundreds of thousands of humans to investigate a protective effect have failed – spectacularly! Six decades ago we assumed that vitamin C was the reason for the better health in populations who consumed high levels of fruits and vegetables – wrong assumption. So then we turned to phytochemicals such as those found in berries, olives, curcumin, grapes, pomegranates and so on as the reason for the benefit. This is where the ORAC concept emerged. The USDA rightly removed their ORAC database in 2010 because it was misleading. As it turned out, the ORAC values were determined by lab bench studies. However, when humans consumed these same compounds, so little of the bioactive compound is absorbed that virtually no antioxidant effect registers in the cells. This is because these polyphenol compounds are such large bulky molecules that they dont get absorbed in sufficient quantity to have an antioxidant effect.

      The way cells protect themselves is by registering stress signals and these signals activate the genes to enable the cell to produce around 2000 protective compounds – the list includes antioxidant enzymes, detoxification enzymes, glutathione, vitamin D receptor and many more. To activate these ‘switches’ in the cell the most effective food compound is the sulforaphane derived from a 100% whole broccoli sprout compound.

      The benefits of the berries and other polyphenols occur largely in the digestive tract, and not in the cells as is commonly thought. Food manufacturers have exploited this flawed theory in marketing so-called ‘super’ foods, Amazonian berries and such like.

      1. I’ve made similar comments (a, b, c, d, e, f). One element of this discussion worth examining more closely is the assumption that ordinary respiration generates the bulk of ROS, but this wonderful paper indicates that’s an artifact of experiments with non-physiological substrates like succinate. Glucose appears to burn relatively “cleanly”, and the major sources of ROS appear to be peroxisomes oxidizing long-chain fatty acids and superoxide generating enzymes like xanthine oxidase, or the NADPH oxidases involved in the oxidative bursts of inflammation. Reducing inflammation is a more attractive option than reducing respiration, and fortunately, many so-called “antioxidants” appear to do just that, though not via their ROS quenching potential.

        1. Darryl, Thanks so much for the link to this paper – this is ‘right up my alley’. You and I are singing from the same song sheet! However, our voices are drowned out by Big Health Food that continues to perpetrate the same sales hype for so-called antioxidant supplements, masquerading as science.

            1. I can’t speak for Annette, but I find the evidence indicates many plant compounds like polyphenols, which function as direct antioxidants in the test tube, do not meaningfully contribute in this way when ingested. Instead they’re doing more complicated things to alter gut microbiota, inhibit inflammatory response, and their oxidized forms may induce our own, more potent and better regulated, antioxidant responses.

        2. Thanks to our forebears–who believed that truth would emerge with freedom of expression. Glucose burns fairly cleanly? So you’re saying that oxidized fats are a more likely source of ROS? Where do those superoxide generating enzymes come from? From the body dealing with oxidized fats? I realize fats get oxidized when exposed to heat, air, light. So the body also oxidizes fats when it burns fats for energy? Could you explain that process?

  2. Dr. Greger, As a vegan who periodically fasts (every couple of weeks I fast for 2-3 days), is there some harm being done because antioxidants/phytochemicals are not consumed during these fasts?

  3. Looking at some of the antioxidant “superfoods” I note that many are very high in C… which leads me to ask if heavy doses of C rich foods meet the bill. Or do the various antioxidants tend to “specialize”, to protect in more specific ways?

    If the latter the USDA list is virtually useless.

    Is the answer simply to eat lots of various fruits and veggies, to seasoned up with a variety of spices… and hope you are getting a balance of antioxidants?

    Surely we can do better than that!

    1. Harvard is basically saying don’t depend on antioxidant supplements, but get antioxidants from whole foods, like fruits and veggies—pretty much what Dr. Greger is saying.

  4. Hello Dr. Greger. I love your videos! Question: You said the Amla Powder (Indian Gooseberry) is the #1 food most rich in antioxidant. How can we be confident that we are consuming enough antioxidants if it’s been processed into powder? Doesn’t powder oxidize quickly?

  5. How about a nutrition facts app that lets us figure antioxidant intake and net anti-inflammatory intake? Either a separate app based on this website alone or an add-on to Lose It or one of the other health apps? I’ve done really well tracking fiber intake with Lose It and would love to have an easy way to track other important nutrients.

  6. Dr. Greger’s site shows
    how important antioxidants are at battling the causes of disease: inflammation, oxidation, wear and tear, dilation, clogging, diffusion (congestive heart failure, more energy for less than peak), inconsistency, erratic changes, uneven pathways, stress (natural responses), damage (IGF-1) missing chunks, nerve movement (brain pattern asymmetry), pain (leaks or exacerbated pores). He suggests that drinking Chai tea, a single cup, has three days worth of antioxidants. Other great sources of antioxidants include oregano, cloves, dried apples, hibiscus tea, matcha or green tea, golden raisins, dried pomegrantes, walnuts, pecans, amla powder or tea, blueberries, rosehips or dog rose (in many hibiscus teas), dried flax seeds, beets, and purple cabbage. These foods are winners in their class and have numerous health benefits that have astounding cumulative benefits. Antioxidant rich foods can stop, delay, reverse, repair, and restore health damage.

  7. What are your thoughts on this scientific study by the BBC program ‘Trust me, I’m a Doctor’ on anti-oxidants? They suggest the daily recommended amount that you are suggesting of anti-oxidants consumption is BAD

Leave a Reply

Your email address will not be published. Required fields are marked *

Pin It on Pinterest

Share This