Although researchers haven't come up with a foolproof way to avoid the gas they produce, they have found a reason why you might want to consider using them. In addition to their high fiber and protein content, a new study finds that beans, particularly black ones, are a rich but overlooked source of antioxidants and may provide health benefits similar to some common fruits, including grapes, apples and cranberries. All beans have the beneficial antioxidants, but black beans came out on top, having more antioxidant activity than other beans, followed by red, brown, yellow and white beans, in that order. In general, darker colored seed coats were associated with higher levels of flavonoids, and therefore higher antioxidant activity.
I fully believe that the flavonoid antioxidant are one of the most exciting areas of nutritional research with supplements. I am a major fan of the flavanoid in grape skin, resveratrol, which can be used to triple the shelf life of fruits and vegetables.
The researchers tested the antioxidant activity of flavonoids ? plant pigments ? found in the skin of 12 common varieties of dry beans. Antioxidants destroy free radicals, which are highly active chemicals whose excess has been linked to heart disease, cancer and aging. The study found that one class of compounds in particular, anthocyanins, were the most active antioxidants in the beans. The levels of anthocyanins of black beans was about 10 times the amount of overall antioxidants in an equivalent serving size of oranges and similar to the amount found in an equivalent serving size of grapes, apples and cranberries.
Some of the healthy antioxidants in beans will be lost in water upon cooking, but antioxidant levels will still remain high after cooking. One does need to be careful though about using large amounts of beans as they are relatively high in carbohydrates and will tend to increase insulin levels. So, if you are struggling with weight, high cholesterol, diabetes or high blood pressure, you will want to use them cautiously.
Journal of Agricultural and Food Chemistry December 31, 2003 (not yet published)