A phytochemical believed to be responsible for the life-extending benefits of red wine may improve quality of life for the elderly, according to a study conducted by researchers from the National Institute on Aging and Harvard Medical School, and published in Cell Metabolism.

Prior studies have demonstrated that the phytochemical resveratrol lengthens the lives of yeast, flies, worms and fish. Research has also demonstrated that it improves the health and lengthens the lives of obese mice on a high-fat diet.

In the current study, researchers gave a daily resveratrol supplement to middle-aged mice that were on either a normal or calorie-restricted diet.

Scientists have discovered that animals consuming 30 to 50 percent less calories than normal live significantly longer, show less age-related cognitive and physical decline, and have less risk of age-related diseases and stress than animals eating a normal diet.

"But we can't have half of America going permanently on a diet," said researcher Rafael de Cabo. "It's not practical, and it's not going to happen."

Mice that were given resveratrol experienced the same improvements in heart, bone, muscle and liver health as mice on a calorie-restricted diet. All the resveratrol-supplemented mice also exhibited improved health and vigor over the long-term, but they did not actually live longer. The chemical only appeared to increase the lifespan for animals on a high-fat diet.

Resveratrol is found in high levels in grape skins and red wine, and smaller quantities in the crusts of peanuts and walnuts. But researchers are not yet sure if drinking red wine would produce the same effects as resveratrol alone.

"It's very hard to extrapolate from this finding to comment on the benefits of red wine directly, because red wine has many other compounds besides resveratrol, including ethanol [alcohol], which has very active biological effects," de Cabo said. "But red wine is a good source of resveratrol … if these effects translate into humans, it will have a very good impact on the standard of human health."

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