Alpha-Carotene, Beta's not-so-little sister?

Just before Thanksgiving, I came across this article published in the Archives of Internal Medicine. In short, the authors analyzed data from 15,318  adults who participated in NHANES, and followed them over a 14-year period.  Carotenes are antioxidants, and it has been hypothesized that they may lower risk for cancer and cardiovascular disease. In this case, the authors discovered that those adults with the highest blood concentration of alpha-carotene had the lowest risk of death from all causes - yes, this includes cancer and CVD.

Now, while this is quite intriguing, please note that it is an association, which does not establish cause and effect. Still, this article highlights something I often explain: that nutrients cannot replace food.

Most people know that beta-carotene is nearly synonymous with vitamin A (it into the active form of vitamin A within the body). The source of vitamin A in most multi-vitamins is beta-carotene. Most people can easily identify food sources of beta-carotene: carrots, sweet potatoes, kale, etc. But beta-carotene is just one of many carotenoids found within these foods. If you are not eating food - if you are relying on vitamin supplements or fortified products - you are truly denying yourself of the full benefits of a healthy diet. There is so much we don't know about antioxidants. I wouldn't trust a supplement company to know which ones are the best for you - I'd trust food.

This reminds me of a lecture I attended at FNCE (Food and Nutrition Conference and Expo) in early November. The speaker, Dr. David Nieman, discussed his extensive research on quercetin, a flavanol, and immune function in athletes. Dr. Nieman is the director of the human performance lab at Appalachian State University. It is well known that athletes suffer from suppressed immunity after an intense exertion, leading to increased rates of illness and inflammation. One of the main findings of years of research is that quercetin produces greater beneficial effects in combination with other flavanols. Alone, quercetin did reduce illness rates, but had no effect on immune response,  inflammation or oxidative stress. Dr. Nieman's research was primarily sponsored by the Department of Defense (Peak Soldier Performance program to examine the effectiveness of quercetin in protecting immune systems of warfighters during missions) and Coca-Cola, owner of Powerade.

While the levels of quercetin tested would be impossible to receive from food alone, I still found it striking that Dr. Nieman's research shows that flavanols act synergistically. In other words, they are more than than the sum of their nutrient parts.