Resveratrol is strongly associated with red grapes and red wine made from grapes. Wines such as Malbec, Petite Sirah, St. Laurent, and Pinot Noir have the highest resveratrol content. Malbec grapes have the thickest skin and, therefore, the highest content of resveratrol.
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How the wine preparation process determines resveratrol content
The concentration of resveratrol in any given red wine depends on the region it comes from. Dark red and purple grapes have a higher concentration of this polyphenol. The concentration in wine varies, however, mostly with the wine-making process used, rather than the type of grape that goes into the wine.
Traditional wine-making techniques produce the highest concentration of resveratrol in red wine as compared to carbonic maceration. For full extraction of various plant pigments and antioxidants from the grape skins and seeds, the wine needs to be in contact with them until the fermentation process is complete.
The skins floating on the top should be pushed down repeatedly when the wine is stirred so that they and the seeds are in increased contact with the wine. Red wine that is prepared through this method has the highest resveratrol concentration.
Health benefits of wine
Red wines have a resveratrol content (per 5-oz glass) of 0.03-1.07 milligrams (mg), which is comparable to the resveratrol content in white wines, which is typically in the range of 0.01-0.27 mg. Red grape juice contains 0.017-1.30 mg per 5 oz.
There is a considerable amount of debate surrounding the question of whether the known heart-healthy actions of a moderate glass of red wine every day are due to the resveratrol or the alcohol content of the wine. This is fuelled by the fact that resveratrol has not yet been shown to increase the lifespan or reduce mortality in a healthy older population.
Yet, alcohol has the following independent effects that contribute to reduced atherosclerosis risk and a 20-30% reduction in coronary heart disease:
- Increases high-density lipoprotein (HDL)
- Lowers low-density lipoprotein (LDL)
- Reduces blood pressure
- Prevents blood clot formation
The truth about red wine
Wine consumption and health considerations
Would grape juice produce the same effects as red wine? Apparently, despite the high resveratrol concentrations in the latter, their results in terms of actual health are comparable.
What does a healthy glass of red wine mean? It could be translated into 1-2 5-oz glasses of red wine, or just one for women. This is because the female body has lower water content, leading to a higher alcohol concentration.
Knowing the all-too-familiar side effects of too much alcohol, including alcoholism, liver damage, brain damage, mental problems, diabetes, high blood pressure, stroke, and heart disease, as well as cancer, the unclear correlation between resveratrol and heart health should not be interpreted as a license to imbibe red wine freely.
An after-dinner glass of red wine makes for an enjoyable sip; however, the consumption of more alcohol than this is not a healthy practice in view of the evidence gathered so far. Those who abstain from alcohol can still enjoy the health benefits of resveratrol from non-alcoholic red wine and red grape juice.
Alcohol is more likely to be responsible for the heart-healthy effects of red wine than resveratrol, in humans, according to our present state of knowledge. Yet, red wine can turn into an enemy if too much of it is consumed as a result of the adverse health effects of the alcohol in it.