cheeky with you Carolyn, but hasn't it proven that H2S is the major gas in flatus? Which would mean that ANY sulfur containing molecule has, as is it's final metabolite, either hydrogen sulfide or methane sulfide. So that the sulfur containing amino acids like cysteine, and all the sulfur containg molecules in onions, shallots, leeks, etc, Should provide the same health benefits that garlic does.
I have read a lot about garlic over the years and the chemistry has been fairly well elucidated. Early work suggested that garlic had significant health benefits, especially in the cardiovascular area, but a few later reports (sorry, i can't find references here) seemed to nullify earlier work.
I for one don't care though, my annual consumption of garlic alone is measured in kilograms. YOu could say, i stink