'No surprise' studies: In healthy people, resveratrol maintains rather than improves health

The newest study investigating the dietary supplement resveratrol (the second within a month) found no physiological improvement in overweight but otherwise healthy people. Investigators from Denmark studied 26 obese men in their early 40s who were otherwise healthy. They gave them resveratrol supplements daily for one month and at the end of the study, again found this same group remained healthy. In a prior study from the University of St. Louis, healthy, normal-weight older women were given resveratrol for three months and also remained healthy at the end of the study.

Both studies were reported as indictments to resveratrol supplementation. I have come to a different conclusion. Because resveratrol failed to improve already normal blood glucose, blood pressure and cholesterol levels, the obvious conclusion is that taking resveratrol supplements keeps you healthy during clinical trials.

As you can surmise, these studies require a tremendous amount of effort, time and money and their results generally could have been predicted. Even the Denmark researchers concluded:

“In future studies, before making any definitive conclusions, the therapeutic potential of resveratrol should be tested in patients with more morbidity such as (actually having) type 2 diabetes, nonalcoholic fatty liver disease and hypertension.”

As with any supplement, resveratrol does not have the capacity to make you better if you are already at a normal level of health. In these recent studies perhaps the investigators believed that obesity in men or being a woman in your 50s were, in fact, medical conditions. But if this is true, why did the most recent study use only marginally obese men whose average BMI was just 32.5 (obesity is BMI > 30) and an average weight of 235 pounds? They also targeted a relatively young age group by eliminating two much older subjects in the resveratrol group (60 and 68 years old). Their average age was only 40 years old. These were healthy men in early middle age, not your typical research subjects.

Resveratrol acts as a powerful antioxidant and also interacts with numerous epigenetic pathways to influence cellular DNA to improve function and enhance a number of metabolic systems in the human body. This is why it is so intriguing to investigators and why many more human studies with resveratrol are being done. In the areas of heart health, diabetes, insulin sensitivity and control of inflammation, to name a few, resveratrol research has been built on numerous positive animal studies, and soon a wave of studies will be reporting on human benefits for these conditions.

When investigating resveratrol or any other dietary supplements in already healthy groups, researchers should be focused not on improving the health of people who are at normal levels. Studies should investigate disease prevention and maintaining health over the long term. Equally important, studies that last a month, three months or even three years may be too short to show the long-term benefits of daily resveratrol supplementation in slowing or stopping the development of health conditions.

A great example of long-term supplementation goes back to one of the first discoveries about the health benefits of resveratrol, not as a supplement, but as found in red wine. Referred to as the “French Paradox,” in the late 1980s, scientists began to notice that despite a high-fat diet, as a whole, the French population had a significantly lower risk of heart disease compared to people in countries like the United States who ate even fewer saturated fats. They concluded that in addition to the fatty foods, the French also consumed the most red wine, per capita, and that something in the red wine was providing this benefit.

Of course we know today that “something” was resveratrol and the other healthy polyphenol molecules that are found in the skins of red grapes. Now studied throughout the world as a dietary supplement, resveratrol has been shown to offer a wide variety of health benefits for humans. Despite the expense and commitment required, it is time for researchers to consider long-term studies using dietary supplements to track human health over decades to determine their true preventive benefits. 

Morten M. Poulsen, Poul F. Vestergaard, Berthil F. Clasen, et al, High-Dose Resveratrol Supplementation in Obese Men An Investigator-Initiated, Randomized, Placebo-Controlled Clinical Trial of Substrate Metabolism, Insulin Sensitivity, and Body Composition, Diabetes November 28, 2012

Jun Yoshino, Caterina Conte, Luigi Fontana, Bettina Mittendorfer, Shin-ichiro Ima, Kenneth B. Schechtman, Charles Gu, et al, Resveratrol Supplementation Does Not Improve Metabolic Function in Nonobese Women with Normal Glucose Tolerance,  Cell Metabolism 16, 1–7, November 7, 2012

Joseph C. Maroon, MD, FACS, is a neurosurgeon, health and fitness expert, and Ironman triathlete. He is chairman of GNC’s Medical Advisor Board and senior Vice-President of the American Academy of Anti-Aging Medicine. He is the author of The Longevity Factor: How Resveratrol and Red Wine Activate Genes for a Longer and Healthier Life. He is the author or co-author of 40 book chapters, and author of six books in addition to more than 250 published scientific papers. He has edited three additional books, has given more than 140 national and international presentations, often as a visiting professor, and has served on the editorial boards of five medical journals and three neurological journals. He has been the team neurosurgeon for the Pittsburgh Steelers since 1981, and is consistently listed in “America’s Best Doctors.”