(flickr, Ani Od Chai)

The ‘don’t worry, it’s good for you’ quip is often used to justify an indulgence that may have limited health benefits, if any. (Yes, French fries are technically a vegetable, but is the nutrition contained the fried potato worth the hefty helping of calories?) 

With red wine and dark chocolate, however, a steady stream of research has given health-conscious people reason to consider stocking their wine cellars with Pinot Noir. 

But exactly how are these commodities ‘good for you’ and how much would you need to consume to see any health benefits?

The ‘miracle molecule’

The molecule that does most of the healthy heavy lifting in red wine and dark chocolate is called resveratrol.  Resveratrol is a molecule that is found naturally in drinks and foods, such as red wine, dark chocolate, peanuts and grapes.  Resveratrol entered the medical and scientific lexicon in a 1939 Japanese study on the poisonous plant veratrum album, when scientist Michio Takaoka was able to isolate the beneficial effects of resveratrol from its deadly host.

Since its discovery, many studies on resveratrol find that this naturally occurring molecule carries with it a multitude of highly coveted health benefits that doctors and patients would love to harness.

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For example, one 2008 study found that resveratrol has protective effects against obesity.  It was shown to protect mice that were fed high-calorie diets from the health consequences related to obesity-- though perhaps not obesity itself--by mimicking the effects of calorie restrictions.  In the same study, resveratrol was also found to prevent pre-fat cells from converting into mature fat cells and to hinder fat storage.

The catch

Resveratrol has two serious limitations that keep wine and dark chocolate from becoming the gold standards of health foods.

First, only trace amounts of resveratrol are found in foods such as red wine and dark chocolate.  Second, the human body does not efficiently absorb even those trace amounts of resveratrol from both food and drink.

So, only extremely large quantities red wine or dark chocolate would need to be consumed to gain any noticeable health benefits. 

What resveratrol can do now

Still, resveratrol itself continues to show great promise. 

For example, in one study from American and Italian scientists, it was found to halt the growth of breast cancer cells. 

According to the findings, resveratrol can block the effects of estrogen by reducing the number of estrogen receptors in breast cancer cells themselves.  This counteracts the malignant progression of breast cancer cells that depend on estrogen to grow and thrive.

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Another study found that resveratrol could help older adults maintain their balance and avoid potentially life-threatening falls as they age.