Spaceflight has a number of deleterious effects on health, but recent evidence suggests that resveratrol – a polyphenol antioxidant from red wine – might help to offset some of these effects. If you ask me, not having access to wine with dinner is bad enough, but there is a long list of physical deteriorations that occur with prolonged zero gravity. These include muscle wasting and decrease in bone density, but there are also physiologic alterations such as insulin resistance and a shift from fat metabolism to carbohydrate utilization. These are issues with a months-long stay in the international space station, but extrapolating to the time required for planetary exploration they become serious problems.
A study on rats suggests how resveratrol may help protect against these changes. While the animals were not launched into space, there is an experimental model that mimics the effects to some degree by “unloading” the hind leg. This results in loss of muscle mass, decrease in bone density, and the associated metabolic changes. With resveratrol added to the diet, these changes were completely prevented, including insulin sensitivity and dietary fat processing.
What this means for us terrestrials may be the more intriguing question. Is wine a subsitute for exercise? Previous studies have suggested that resveratrol enhances athletic performance, and slows age-related muscle loss (again in mice only.) There is some evidence that muscle wasting from cancer may also be slowed with resveratrol supplementation. However, several studies support the use of another wine polyphenol, quercetin, for boosting athletic performance and endurance, and the optimal combinations and dosages remain to be determined.
It is of course important to recognize that people are not rats (at least metabolically if not behaviorally) and this notion is completely untested in humans. Absorption and the biological availability of resveratrol in people is different than in rats and so we can’t read too much into this. What we do know is that wine drinkers are healthier and live longer on average, and it appears to be related to a number of things besides resveratrol. The real trick of course will be stocking the space cellar.