Vitamin D isn’t just for bones. Many cell types have vitamin D receptors, and a new study from McGill University shows that vitamin D can act at the molecular level to inhibit cancer cell proliferation. This study looked at the effect of vitamin D on production of a protein called cMYC, which controls cell division. cMYC activity is especially high in cancer cells. Vitamin D can help stifle cMYC activity, which may slow development of malignant cells. Other studies have linked vitamin D status to lower risk for many cancers, but a metabolic explanation has been lacking. The effect of vitamin D on cell growth factors like cMYC offers a clue.
Evidence for a health benefit from resveratrol is lacking, and a new study doesn’t change that. Resveratrol is the antioxidant found in wine that’s been hyped for supposed health benefits. People who drink red wine in moderation have lower risk for heart disease, cancer, diabetes and aging. Simplistic conclusion: something about red wine is healthy, and that must be the resveratrol. However, resveratrol claims are based on test tube studies, not on actual health outcomes in humans. Resveratrol may not be absorbed very well, and once absorbed appears to be quickly metabolized and excreted. In this study, obese men were given daily supplements of resveratrol or a placebo. Insulin sensitivity and markers for heart health did not improve in the resveratrol group. So why do moderate red wine drinkers seem to have better health? Most likely they have an overall healthier lifestyle.
Omega-3 studies published recently seem to question whether these unique fatty acids provide much health benefit after all. One study claimed no benefit, since omega-3 consumption didn’t cure heart disease or lower cholesterol. It seems medical researchers are making the big mistake of confusing a nutrient with a drug. A new review from the renowned Linus Pauling Institute concludes that omega-3 fats are valuable for prevention of disease, but are less useful as a cure-all. One complication of current studies is that many of the study subjects with existing heart disease are already on several prescription drugs, which will obviously complicate results. Another problem: omega-3 intake is never standardized in most of these surveys. Since there are so many different omega-3 supplements, made from so many different sources using different techniques, it’s impossible to compare results. Take home message: omega-3 fats are a critically important nutrient, necessary for health. They are not drugs.