By Alisha Mehta
For many years red wine has been touted as the “heart-healthy” drink and recent discoveries have popularized several additional health benefits. The most prominently studied compound in red wine is resveratrol, the antioxidant present in grape skins. Unlike white wine, red wine uses the skins, seeds, and stems during the fermentation process, which preserves the resveratrol, accounting for many of these proposed health benefits. However, white wine also contains compounds presumed to have some benefits as well. Other food sources of resveratrol include peanuts, blueberries, bilberries, and cocoa beans.
Resveratrol, or the “compound du jour”, as Stephen Taylor, a researcher from the University of Queensland called it, offers many potential health benefits. Studies have shown that resveratrol may be able to prolong life due to its beneficial effects on cholesterol, heart disease, cancer, obesity, diabetes, and even other diseases. The latest study, which received a lot of media attention, touts resveratrol for its ability to decrease the metabolic effects of obesity and thus helps prevent the onset of age-related disease.
What’s the latest hype on resveratrol? A small Dutch study published in the November issue of Cell Metabolism shows that resveratrol may mimic the effects of diet and exercise on the metabolism of obese men. Previous findings have shown improved metabolic effects in rats fed high calorie diets, as well as with isolated human fat cells. However, this is the first study to show promising results in a clinical trial.
In this study, a small group of eleven obese, but otherwise healthy men were given 150 mg/day resveratrol supplements for thirty days. Twenty-nine bottles of the richest red wine would have to be consumed to obtain an equivalent dose. The findings showed improvements in blood pressure, blood glucose levels, decreased liver fat, and increased insulin sensitivity. In addition, sleeping and resting metabolic rates were lowered, indicating improved metabolic efficiency. The researchers found resveratrol supplements mimicked the effects of calorie restriction or endurance training. Thus, resveratrol supplementation may have the potential to improve metabolic health in individuals and delay the onset of obesity-related disease, including, cardiovascular disease and diabetes.
For years, we have been hearing that red wine, when consumed in moderation, may play a role in lowering cholesterol and preventing heart disease. Resveratrol has been studied for its role in a number of cardiovascular problems, such as myocardial infarction, hypertension, and atherosclerosis. A 2009 review of animal and cell studies in Alcoholism: Clinical and Experimental Research showed that resveratrol activates SIRT1, an enzyme important for several aspects of lifespan regulation, cellular response to stress, glucose homeostasis, insulin secretion and homeostasis, vascular tone and endothelial dysfunction. The effect of resveratrol on SIRT1 seems to be the mechanism responsible for many of the cardioprotective outcomes. Through its roles in reducing LDL cholesterol, preventing damage done to blood vessels by LDL cholesterol, preventing blood clots, and reducing inflammation that can lead to heart disease, resveratrol has won a lot of attention.
As an antioxidant, resveratrol plays several roles in reducing oxidative stress, possibly preventing the onset or further development of cancer. By increasing nitric oxide bioavailability, resveratrol may reduce oxidative stress to protect against exposure to UV radiation, free radicals, and damage to DNA. Resveratrol has been said to be effective against both precancerous and cancerous cells because of its potential role in attacking free radicals before they become harmful. The protective effects of resveratrol have been studied in vitro (outside the body in a petri dish) as well as in mice. To date, studies in humans have not shown the same results but resveratrol has the potential to work as a cancer chemoprevention treatment. Resveratrol may also benefit the immune system by aiding the production of cytokines, white blood cells essential for the response to infections in their role in reproduction, growth, immunity, and tolerance. Researchers are still perplexed by the apparent contradiction of resveratrol both serving as a cardioprotective and neuroprotective agent, yet killing cancer cells. It is thought that there are dose-dependent effects and low-dose resveratrol is protective, while high doses initiate cell death signals. However, clinical trial data to support this is not yet available.
Though these findings are exciting, research studies such as these always need to be regarded with caution. Can a resveratrol supplement replace diet and regular exercise? Of course not. Most previous studies have been based on animal studies or cells in culture, while the actual effects could vary in humans. Furthermore, the effects of long-term supplementation are yet unknown. However as the first human study demonstrating the use of resveratrol in alleviating the problems associated with age-related diseases, the results are promising.
- Brown et al. The Biological Responses to Resveratrol and Other Polyphenols From Alcoholic Beverages. Alcoholism Clinical and Experimental Research, 2009; DOI: 10.1111/j.1530-0277.2009.00989.x
- Timmers, et al. Calorie Restriction-like Effects of 30 Days of Resveratrol Supplementation on Energy Metabolism and Metabolic Profile in Obese Humans. Cell Metabolism, 2011; DOI 10.1016/j.cmet.2011.10.002
Alisha is in her second year at the Friedman School as a dual Nutrition Communications/DPD student and is excited to soon become a Double Jumbo. She is a true California girl, enjoys traveling, trying different types of fitness classes, and attempting to create healthier versions of recipes. Alisha records her recipes she finds blog-worthy at SavortheFlavour.