Please raise your left hand if you believe consuming antioxidants is beneficial. Raise your right hand if you believe taking antioxidant supplements, self-prescribed, is an equally good idea.
My left hand is reaching for the ceiling, waving wildly as it did when I was in Grade 3 and really needed quick permission to hit the washroom. There isn’t a day that goes by without breakfast including a quarter cup of blueberries, half a Kiwi, 10 frozen cherries, a small beet, half a banana, and 10 raspberries or six strawberries — boring for sure, but good for at least 120 mgs of Vitamin C.
My right hand?
It’s hidden behind my back, ashamed to admit that prior to doing the research for this column, I also took one 500 mg Vitamin C supplement with breakfast every day. That would be 620 mg of Vitamin C total, while the Canadian Recommended Dietary Allowance is 75 mg for women and 90 mg for men. I’m dosing seven times what’s recommended for a whole day before 9:00 a.m.
A week ago a friend shared a link to a 2013 Scientific American article by Melinda Wenner Moyer, “The Myth of Antioxidants.” In it she writes that in 1954 Denham Harman, a research assistant at University of California, Berkeley, devised a study from which he concluded that “aging must be driven by free radicals,” and that consuming large quantities of antioxidants, known free-radical fighters, would slow the aging process in humans.
Moyer noted that in the decades afterward Harman’s theory became ubiquitous, even though no one was able to replicate his study’s results. Her article asserted that these results were now (2013) in doubt—that antioxidants did not slow the aging process and may, in fact, be bad for our health.
Reading Moyer’s article was simultaneously calamitous and cautionary. I desperately needed a verifiable “Yes, Virginia, there is a Santa Claus,” type of reassurance that my years of slavish antioxidant over-consumption hadn’t been in vain, or I needed proof that I was misinformed.
Very briefly, here are the main players—free radicals and antioxidants—and their roles
Free radicals are molecules within our body that are unstable because they don’t contain a complete set of electrons. Consequently, they attempt to steal electrons from other molecules. While doing so they damage our cell membranes, DNA, and other cell components.
Free radicals occur naturally in our bodies, created by our immune system to defend against infection, assist cells to communicate, including communication between muscles and insulin during exercise, and to aid with other biological processes.
Current science is proving that Harman’s 1954 hypothesis is a gross oversimplification
When we have too many free radicals they overwhelm our naturally produced antioxidants, causing a condition called oxidative stress, which has been linked to aging, heart disease, diabetes, cancer and other diseases.
Antioxidants fight, or neutralize, free radicals by surrendering some of their own electrons to shut down the free radicals’ activity. Our bodies manufacture antioxidants, including alpha lipoic acid for converting glucose to energy and glutathione, a multi-beneficial compound. However, most of what we need comes from fruit, vegetables and other plant-based whole foods high in Vitamins C and E, beta-carotene, carotenoid and flavonoids.
So far, so good. Our body creates free radicals and antioxidants, they both perform essential roles, and our antioxidants control our free radical population to avoid oxidative stress. What’s the problem?
The problem is that many of us may be overindulging in antioxidant supplements without understanding the consequences.
Current science is proving that Harman’s 1954 hypothesis—which was inspired, by the way, from his reading an article in Ladies Home Journal— is a gross oversimplification which doesn’t take into account that most food compounds and their nutrients work in balanced synergy, and sometimes antioxidant supplements can produce too much of a good thing.
Remember the 500 mg Vitamin C (antioxidant) supplement I consume every morning? I double it when I feel a cold or any sort of potential ailment coming on.
Here’s what Katherine Zeratsky, a certified dietician with the Mayo Clinic, has to say about this type of behaviour: “For most people, a healthy diet provides enough vitamin C. Although too much dietary Vitamin C is unlikely to be harmful, large doses of Vitamin C supplements might cause nausea, diarrhea, vomiting, heartburn, abdominal cramps and headache.”
Then there’s beta-carotene, the antioxidant derived from yellow and orange coloured fruits and vegetables, which our bodies convert to retinol, an A vitamin.
A multi-authored meta study by Mount Sinai Institute confirmed Vitamin A fights age-related macular degeneration, strengthens our immune system and aids in maintaining healthy skin and mucous membranes. Our body only converts as much beta-carotene into Vitamin A as it needs, so the study concludes that although “big doses of Vitamin A can be toxic, getting high amounts of either Vitamin A or beta-carotene from food is safe.”
Yet it goes on to say, “However, too much beta-carotene can be dangerous for people who smoke. Beta-carotene supplements may increase the risk of heart disease and lung cancer in those who smoke or drink heavily.”
The benefits of using antioxidant supplements gets even cloudier because there are, “probably thousands of different substances that can act as antioxidants,” according to a Harvard University study. Antioxidants perform a chemical rather than nutritional reaction with free radicals—they donate electrons, and in this capacity antioxidants are not interchangeable.
The Harvard study elaborates further: “Some substances that act as antioxidants in one situation may be pro-oxidants, electron grabbers, in a different situation. This means that no single substance can do the work of the whole crowd.”
Last one.
The United States Department of Health’s National Centre for Complementary and Integrative Health states, “As research has progressed, it has become evident that antioxidants, especially in larger-than-usual amounts, may not always be beneficial. Large amounts of antioxidants may interfere with important functions in the cell, including defense mechanisms and normal signaling.”
What does this all mean?
As someone who has no formal education or training in the fields of diet or nutrition, but just wants to keep riding his bicycle forever, I can only speak for me. In that context, this information is but one more proof of how important a natural, whole food diet is to our health, of the need to educate ourselves with current, scientifically verifiable health and product information, and that balance and moderation have once more won the day.
Anyone want half a bottle of Vitamin C tablets cheap?
Please do your own research—there is no shortage of cautionary articles online, from reputable institutional sources—and consult your doctor as required.
(John Swart, of Fonthill, has been a cycling enthusiast since the 80s)
