In the natural BB-ing world this is pretty common knowledge. I know Skip Lacour recommended eating redwine vinegar with every meal to help digest food and starve off the effects of metabolic slowdown from hard dieting. I also have seen the effects help females tremendously.
Good stuff, it does seem to have positive effects on insulin sensitivity and of course blood sugar/ kidney function. I used to take a bit everyday, might have to try it again. 15ml chased with some oj isn't to bad.