Are those extra antioxidants good for you? [Credit: Photo by Daniel Sanbec. Compiled by Karina Hamalainen]
“Now with Lycopene!” “Full of cancer-fighting antioxidants!” “Pomegranate juice?!” These are all thoughts that might have crossed your mind the last time you went grocery shopping. It seems like every food product, especially those considered bad for you, is being advertised as packed with antioxidants. But are antioxidants a miracle cure that ensures a diet of gin, chocolate and coffee will keep you free of cancer? Unfortunately, these dietary antioxidants aren’t all they’re cracked up to be.
The crux of the matter is the difference between the antioxidants you get from food and the ones your body makes naturally. Not only does your body already make all the antioxidants it needs, but also none of the studies that investigated the effects of dietary antioxidants have shown any significant benefit.
All plant and animal cells naturally produce antioxidants to mitigate the danger of free radical oxygen molecules. These molecules are highly chemically reactive and cut through DNA like a chainsaw through marshmallow. Once that DNA is damaged, a cell can die or start down the road toward cancer.
To prevent DNA damage, cells produce antioxidants, chemicals that bond to oxygen before it has a chance to cause any trouble. Thus, the reasoning went, if our natural antioxidants could be bolstered by antioxidants from food, even more oxygen could be captured and our risk for cancer should be reduced even further.
In the late 1970s, researchers began to look for ways to supplement the antioxidants naturally produced by the body through a diet heavy in plant antioxidants. Immediately, newspapers began to report that these foods could prevent cancer.
Since then, research into antioxidants has followed two tracks. One examined the effects of antioxidants in a test tube, while the other looked at the effects of dietary antioxidants in live human subjects. The results of the test tube experiments led to claims that diet-supplemented antioxidants can prevent cancer or treat pulmonary fibrosis, while the live studies reported that antioxidants have no health value or may even be dangerous.
The discrepancy results from the differing methodology of the tests. The test tube studies just involve submitting a chemical or food product to the “oxygen radical absorbance capacity,” the Food and Drug Administration standard for testing the antioxidant property of a chemical. The test involves measuring fluorescent dye decay after the target food or chemical has been exposed to oxygen.
By contrast, the live experiments have been case studies. These tests involve feeding subjects the antioxidants, monitoring them over a long period of time and comparing the results to a group that had been given a placebo.
The optimism over the potential for dietary antioxidants to prevent cancer or aging results from the test tube studies failing to consider how antioxidants are metabolized or how they act within a cell. Conversely, the live studies test all of the variables.
The test tube studies are overrepresented in antioxidant news coverage. That is because they make up the bulk of antioxidant research (as it is far cheaper and easier to conduct an experiment on a chemical than on a human) and are often well suited to mass media coverage. By presenting claims that desirable but formerly maligned foods like chocolate, wine, coffee and even martinis might be healthy, these studies tend to garner a lot of attention.
As a result of the failure of any live study to show any health benefits from antioxidant supplements, neither the National Cancer Institute nor the American Heart Association endorse antioxidant dietary supplements as an inhibitor of heart disease or cancer.
So, despite what the label might tell you, there’s still no evidence that fancy juices, fattening sweets or any kind of booze will prevent cancer. However, eating chocolate and drinking bourbon will, in my experience, cure sadness.