Maybe you like me have bought in enthusiastically to the idea that a glass of red wine is good for you, we don't ask too many questions do we? Why look a gift horse in the mouth and all that.

In research, scientists reported that overweight, middle-aged mice whose high-calorie, high-fat diet was supplemented by resveratrol had better health and lived longer than chubby counterparts who did not receive it. Resveratrol is a compound found in common foods like grapes, red wine, and nuts.

The study, funded in part by the National Institute on Ageing (NIA) of the National Institutes of Health (NIH), concluded that resveratrol appeared to lower the rate of diabetes, liver problems, and other fat-related ill effects in obese mice.

But don’t rush out and buy red wine or resveratrol supplements just yet, because there is still plenty of room for discussion around this.

For starters, the mice were fed massive doses of resveratrol – 24 milligrammes per kilogramme of body weight. “Red wine has about 1.5 to 3 milligrammes of resveratrol per litre, so a 150-pound person would need to guzzle 750 to 1,500 bottles of red wine a day to replicate that dose and I suppose that if all that red wine did not extend your life, you’d be so drunk you would’t care!

Pills of resveratrol would require huge doses as well. Supplements typically have about 20 milligrammes. The amount used in the study was the equivalent of giving a 150-pound man 1,636 milligrammes, which would be about 80 pills a day.

Megadoses are a scary prospect because absolutely everything, even nutrients, are potentially toxic if given in a high enough dose. For example, beta carotene is a beneficial chemical naturally occurring (in small amounts) in many fruits and vegetables, but massive doses in supplement form increased the risk of lung cancer in smokers. Huge doses of vitamin E increased the risk of heart problems in heart patients.

Indeed, in an NIH press statement, the authors of the resveratrol study cautioned that there was still a lot to learn about resveratrol’s safety and effectiveness in humans.

Some negative side effects are already known. Animal studies have shown that high doses of resveratrol affect blood platelets, which could increase the risk of bleeding when taken with anticoagulant, anti-platelet, or non steroidal anti-inflammatory drugs.

So maybe before we reach for that bottle of red, we should have a little think about it, or at least a little less of it!