Doctor's Note

Here’s that kale video: Smoking Versus Kale Juice. You can also get DNA Protection from Broccoli.

What do antioxidants have to do with heart disease? See The Power of NO.

I strive to eat berries every day and so should everyone else. See Best Berries for the best fresh and Better Than Goji Berries for the best dried. If you’re still not convinced check out the amazing findings in Strawberries versus Esophageal Cancer and Black Raspberries versus Oral Cancer. Are organic berries preferable? See Cancer Fighting Berries.

Instead of hibiscus you can sip whole cranberries. See Pink Juice with Green Foam. If you are going to do wine, red is preferable (Breast Cancer Risk: Red Wine vs. White Wine).

This is the third of a 3-part video series on practical tips to achieve optimum “redox” (free radical versus antioxidant) balance. In Minimum Recommended Daily Allowance of Antioxidants I tried to explain the why and how much and in How to Reach the Antioxidant RDA I got into the nitty gritty of meal planning and described how just reaching the minimum may not be sufficient.

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  • DH

    Off-topic, Dr Greger, but is there any data to suggest that what we feed our children can cause malignancy later on in their adult lives? I understand that childhood is the critical time for pro vs anti-cancer nutrition, but I have been unable to find the evidence…..
    Thanks for your help.

    • Merio

      i think that you got to look out in the field of nutrigenomics/epigenetics… IMHO probably the maternal environment could play a key role to avoid possible genotoxic effect on the baby… want to write more, but out of time… best regards…

    • Darryl

      Some diets may prevent malignancy later in life. The benefit of soy phytoestrogens in breast cancer prevention may be limited to consumption during puberty and just before. There’s a brief discussion in “5. Timing is Everything” of this Nature editorial and in this Cornell brief.

      • DH

        That’s very helpful. Thank you very much.

        • Christo Okulian

          True to Merio and Darryl. DH: in some aspect of health, we learn from study video within this website that cancer/tumor is one of the disease that accumulative within our aging. if someone gets cancer detection now it means the cancer have been growing “rapidly” (because of bad life style and diet so the body failed to fight back effectively the cancer) started from 5-10 years ago.

    • Rachel

      Dr. Fuhrman talks a lot about this and has an entire book that draws together the evidence linking childhood diet to cancer and other health problems in adulthood. http://www.drfuhrman.com/ask/archives/2005_10.aspx

  • John S

    It seems like many of us should be growing berries and leafy greens, because they are expensive in stores and they last longer on the bush than when picked. Many leafy greens are weeds that were originally brought here as nutritious vegetables, such as dandelion, garlic mustard, sow thistle, plantain leaf, shot weed (cress) and burnet salad. Nutritionists when checking them almost always find them more nutritious than store bought vegetables. Easy to grow? They are weeds! People are trying to kill them.
    John S
    PDX OR

  • marge

    I recently saw your video on milk negating the antioxidant value of berries down to zero. Does your research still validate this view? If so, how much time must pass between drinking milk or soy milk and eating berries to get the full benefit of both? Is it also true for the other milks such as almond milk?

    • Darryl

      See pages S78-80 (“Matrix effects”) of this review of berry flavonoids and phenolics. Some studies have shown reduced absorption with milk, others no effect. Its suggested that milk has a greater impact with moderate flavonoid food than with high flavonoid extracts used in research. Not mentioned is this paper, which found addition of cream delayed, but did not reduce, absorption of strawberry flavonoids.

      It appears no research has been done with non-almond polyphenols and almond milk.

  • Catherine J Frompovich

    Great information, except I would add that the strawberries be organically grown since most commercial strawberry growers in the USA can spray with methyl bromide, chloropicrin, and Telone (1,3-D), which have their own pro-oxidative consequences metabolically, especially in the liver and the immune system.

    One other aspect that ought to be considered with regard to this information is the effect(s) of genetically modified crops in the diet, even though they are plants, have on the human organism, since GMO crops are sprayed with inordinate amounts of the chemical glyphosate. Please see this http://www.enveurope.com/content/24/1/24 Shouldn’t we be eating LESS chemically-laden plant foods than more, if we want to maintain optimum health, longer-lasting telomeres, and less pro-oxidative stress?

    • Broccoli

      Thanks for the info….

    • Darryl

      Actually, it seems we’re far more likely to develop cancer from micronutrient deficiencies in vitamins niacin, B6, B12, C, E and especially folate, and minerals iron, zinc, and selenium, than from dietary pesticide exposure (synthetic, organic or the 99.9% intrinsic to plants).

      The benefit from organic agriculture appears to be less from consumer safety than reduced energy inputs and improved soil quality.

      • DH

        So you’d recommend against organic for the time being, as minimization of “less toxic chemical applications” cannot be guaranteed? Or am I mistaking the overall implication? Certainly non-organic is far cheaper!

        • Darryl

          I just wanted to counter Catherine’s statement that non-organic vegetables are harmful. A lack of organic options (not everyone lives near a health food store) is not a good reason to avoid eating plenty of vegetables, as the health benefits of conventional produce still far outweigh any risks. I largely agree with Christie Wilcox on the comparative merits (1, 2). Sustainable, low-chemical input agriculture is possible and desirable, but the marketing category “organic” will never be as informative as meeting your local farmer..

  • moomoo

    Any thoughts on this recent study of heavy metals found in brewed tea?
    http://www.hindawi.com/journals/jt/2013/370460/

    I love the antioxidants, but I’ve been long-brewing (at both cold and hot temps) my tea for years. Now I wonder if I need to curb my tea habit (or at least change my brewing time). No info on how much metal leeches into cold-brewed tea.

    • Darryl

      The main concern would appear to be manganese (1, 2, 3, 4).

      • moomoo

        I am more concerned about the high levels of lead and aluminum.

      • DH

        I was asking more about the personal cost-benefit analysis of consuming organic produce – do you think the benefits of improved health actually exceed the steep costs of organic produce (in Canada, it seems the organic produce is incredibly expensive, perhaps because most of it is imported from down south). Looking forward to your comments…

        • Darryl

          Personally, no. Recognized nutrient content is similar, and antioxidant phenol content is increased through insect herbivory and abiotic stresses, which would make the produce unmarketable. The insect bitten leaf from a home garden may be the healthiest. As noted in links in my response above, its no longer so clear that higher applications of less effective/selective natural source pest and weed control compounds are safer than current “soft” (quickly degraded) synthetics. As for GMOs, I largely agree with former anti-GMO activist and current climate journalist Mark Lynas.

          • DH

            I was not at all aware that synthetic pesticides/herbicides/fungicides/insecticides were quickly biodegradable.

            I was however aware that there are many native carcinogens and pesticides found in plants; hence I have always been skeptical about organic agribusiness claims of “chemical-free” agriculture.

            On balance, from what you’ve written, it does not make much sense to purchase organic produce, even for vegans who consume an extremely large amount of produce.

          • Darryl

            Crop protection chemicals (whether synthetic or natural sourced) are all toxic, but ones in current use don’t persist in the environment and food chain like the the “Dirty Dozen” or “Nasty Nine”, now banned under the Stockholm Convention on Persistent Organic Pollutants. For example, imidan and glyphosate (Roundup) spontaneously degrade in water and soil. The harm that was done during the era of persistent organic pollutant pesticides is exemplified by their continued presence, even in organically grown crops (1, 2, 3)

          • Thea

            Darryl:

            Have you seen this NutritionFacts.org video?:

            http://nutritionfacts.org/video/can-pesticides-be-rinsed-off/

            During 2 weeks of eating organic, the pesticides in the kid’s urine dropped off dramatically. Of course, one could argue that the pesticides normally found in the kid’s urine are no problem. But I can’t imagine how it would be harmless.

          • Darryl

            The EPA decision on chlorpyrifos (the predominant organophosphate found in that study).
            • occupational exposure is a concern, with high doses overstimulating the nervous system causing nausea, dizziness and confusion
            • dietary exposures are lower than 0.01% of the lowest adverse effect chronic dose level seen in animal studies.
            And from this review
            • its not carcinogenic
            • it doesn’t bioaccumulate (note its disappearance from urine in the video)
            • human neurodevelopmental outcomes in agricultural areas did not correlate with urinary metabolite levels.

            Compare that to currently approved organic pesticides: pyrethins, which are carcinogens, or rotenone, which is linked to Parkinson’s in farm workers. We have to wash our organically grown veggies, too.

            Mind, I’m not saying use of organophosphates like chlorpyrifos or pesticides approved for organic agriculture is a good thing (I’d much rather see integrated pest management, companion planting, etc.). Only that (as with a lot of hazards), innumerate fear and marketing language (“all-natural”, “organic” etc) isn’t the best basis for making decisions.

          • Thea

            Darryl: All good points. I believe I understand what you are saying and agree to a point. I certainly “fear” eggs far more than I would fear a conventionally grown say mellon. However, I wouldn’t dismiss your first bullet. For me, that’s important too.

            Also, while I think I understand your point, I think that going organic is likely to give overall advantages. In other words, I would guess that stacking up a random sampling of organic produce against a random sampling of “conventional” produce would show the organic to be less toxic over all. I don’t know that. I just believe it.

            So for me, buying organic when I can does this: 1) sends a message to the capitalists that I care about food safety and the environment (regardless of whether they have actually made it safer by growing organic or not)–hopefully leading to better decisions by those people in the future, 2) helped the farmers who actually work with my food, 3) possibly helped my health.

            That’s really the best I can do at this point in my life. I’m not interested in being a farmer myself or lobbying or grilling local farmers, etc.

            Thanks for your thoughts.

    • Marie S

      I’m already concerned about tea because it’s high fluoride content may be slowly poisoning me and interfering with iodine absorption and utilization. Thanks for posting the final nail.

      • nc54

        white tea is low in flouride

  • jack

    Seems to me that much of this topic is still speculative. Most of the results come from measuring antioxidant effects in a piece of laboratory equipment, a machine rather then the effects in the human body. It could be that antioxidants have no real effect in the human body, or if they do, it’s because of other properties they have other than being antioxidant. Just the same, I find myself eating lots of berries, beans, greens, mushrooms, garlic, onions, broccoli, yams, apples and other vegetables and fruits.

  • Nancy

    All the conflicting dietary advicde from different people with different points of view can get very confusing! What is your reacttion to those who claim that fruits and vegetables should not be combined at the same meal beczause it imp[edes digestion and absorbtions

  • Petra

    Hello Dr. Greger, I love your videos, educational and funny!
    I am wondering about antioxidant rich foods, you mentioned berries like strawberries and blueberries are very high in antioxidants. But I was wondering about the pesticide load on them, from all I know strawberries are sprayed with hundreds of chemicals and I suppose the same goes for blueberries. Buying organic is out of the question for me, considering the price of the berries. I used to pick blackberries and freeze them for the winter, will do that again. Those are never sprayed on, they are actual a bad weed around here.
    Thanks again for all the info you are giving us!
    Petra

    • Thea

      Petra: I think I know where you live! Northwest America? That’s where I live and blackberries are considered a weed here. (And they are in the sense of how they grow and take over.)

      As for your question: Dr. Greger has a great blog post where he puts pesticide consumption into perspective. :
      “A new study calculated that if half the U.S. population ate just one more serving of conventional fruits and vegetables, 20,000 cases of cancer could be prevented. At the same time the added pesticide consumption could cause up to 10 extra cancer cases. So by eating conventional produce we may get a tiny bump in cancer risk, but that’s more than compensated by the dramatic drop in risk that accompanies whole food plant consumption. Even if all we had to eat was the most contaminated produce the benefits would far outweigh any risks.”

      from: http://nutritionfacts.org/2013/06/25/apple-peels-turn-on-anticancer-genes/

      I translate this bit of info into: Eat organic when you can, but don’t stress about it when you can’t.

      Happily, there is a way to take this advice a step further to minimize your risks without completely depleting the pocketbook. Every year, the Environmental Working Group actually measures pesticide levels in fruits and veggies–after those fruits and veggies have been prepared in the way people would normally eat them. (For example, peeling a banana or washing first.) If you scroll down on the following page, you will see a list for the “Dirty Dozen” and the “Clean Fifteen”.

      http://www.ewg.org/foodnews/summary.php

      I bring your attention to these lists because I think they are very helpful for people who can’t afford to eat organic for everything. You could use these lists to help you decide when it is worth putting down money for organic and when it might be safer to buy non-organic.

      One more thought for you: I would say that eating in the season is a good idea. So if you want to eat berries year-round (also a good idea), I personally would eat frozen berries rather than the fresh that is available in the middle of winter. Why? Because it is my understanding that frozen berries are picked when they are grown naturally and still have most of their nutrients and then are flash frozen, retaining those nutrients. Fresh this time of year I would think would have to travel long distances…

      I hope this helps!

  • ak017

    Grading food just by antioxidant content is reductionism and
    may be misleading. Onion, garlic and flax – not high on the charts, especially
    when accounted for their serving size, are nevertheless healthy.

  • Cyndy

    Red Tea. How does Rooibos tea stack up with the others for antioxidant benefit? It’s my favorite!

  • Tobias Brown

    What foods in an excellent plant-based whole foods diet delivery the highest oxidative stress load? And I mean for those of us who don’t use oils.