Resveratrol for a Healthy Heart

In recent years, the media has been buzzing about a phenomenon called the French paradox: the people in France reportedly have a lower incidence of heart disease despite a high-fat diet. This paradox has been associated with wine consumption, and resveratrol, a potent polyphenol in the grapes that wine is made from, has been widely touted as the reason for this effect. Studies have confirmed that resveratrol does exhibit effects that can be beneficial to the cardiovascular (and other) physiological systems. Even those that question whether resveratrol could be the sole explanation of the French paradox—since it would seem to take 52 bottles of wine a day to replicate the amount of resveratrol in certain positive studies—acknowledge that resveratrol appears to be beneficial to cardiovascular health.⁷⁴ Additionally, in some animal studies high doses of resveratrol only exerted a minimally greater positive effect on certain cardiovascular functions than the much lower doses—suggesting that the 52 bottles of wine figure does not reflect the true benefits of much lower amounts of resveratrol once ingested.⁷⁵

Research has consistently shown that chronic inflammation can cause a number of health conditions, including cardiovascular disease (and others that contribute to it). Reports suggest that some of resveratrol’s preventive and therapeutic effects may be due to its antioxidant and anti-inflammatory properties.⁷⁵

For example, resveratrol has been shown to inhibit the dysfunctional production or activity of pro-inflammatory proteins associated with the development of heart disease, such as the COX and tumor necrosis factor-alpha enzymes. In animal studies, resveratrol appears to help the heart develop resistance to damage due to reduced blood flow, probably by promoting the production of nitrous oxide (commonly abbreviated as NO) and antioxidant proteins which protect cardiovascular cells.⁷⁵

Although resveratrol did not seem to have any effect on hypertension in some rat studies,⁷⁵ other research indicates resveratrol is able to relax and dilate blood vessels, which could help lower blood pressure.⁴⁵ Numerous animal, laboratory, and human studies or clinical trials have demonstrated that resveratrol exerts multiple heart benefits:

Evidence of Benefit

The beneficial cardiovascular effects demonstrated by resveratrol matches those seen in a group of individuals who had engaged in long-term significant (25%) calorie restriction.⁷⁴ A recently published (2010) randomized, double-blind clinical trial involving healthy but overweight and obese men suggests that resveratrol, in combination with other anti-inflammatory substances naturally found in a variety of food, may offer some similar benefits—without changes in dietary intake or exercise.⁸²

The participants were randomly assigned into groups and given either a placebo or the supplemental dietary mix, which included resveratrol, fish oil, vitamins C and E, green tea extract, and lycopene from tomato extract. Although the supplements did not decrease C-reactive protein (CRP) concentrations, they did show a measurable effect on a number of other inflammatory, metabolic, and oxidative indicators. Potential participants were excluded if they took any pharmaceutical anti-inflammatory drugs on a regular basis, so the benefits could not be attributed to substances other than the supplements. All results were measured by blood tests and weekly biopsies of fat tissue from the abdomen during the 5-week study, which profiled genes in addition to proteins and metabolites. One unexpected result was a decrease in prolactin, a protein hormone produced by the brain that regulates metabolism, weight, and the development of pancreatic islets .⁸²

Another clinical trial conducted at a diabetes and endocrinology center in New York found that resveratrol supplementation suppressed a number of inflammatory factors, including CRP, in healthy people with normal weights.⁸³ Levels of CRP are indicative of acute and inflammatory conditions in the body, including atherosclerosis .⁸⁴ Research indicates that CRP levels are associated with greater cardiovascular risk levels than either cholesterol or blood pressure, and is recognized as an important indicator of heart health by both the Centers for Disease Control and Prevention (CDC) and the American Heart Association (AHA).⁸⁴

In this study, 20 people were randomly assigned to one of two groups of 10 subjects. One group was given an herbal supplement containing 40 mg of resveratrol as the active ingredient, while the control group was given a placebo. Each subject took either the supplement or the placebo once a day for six weeks, and had blood drawn to test for inflammatory markers and free radicals after one, three, and six weeks. Compared to baseline blood measurements, the resveratrol-treated group had significantly less free radicals and a number of inflammatory markers—both of which contribute to development of conditions such as diabetes, heart disease, and cancer.⁸³

So while resveratrol may not be the only explanation for the apparently good heart health of those with a reportedly high-fat diet, evidence indicates it may certainly play a beneficial role. This is not to suggest that resveratrol can replace a wholesome diet and regular exercise, but that it may synergistically improve the outcomes of these aspects of a healthy lifestyle.