I think "ad libitum" means "as much as you want", i.e. enough to satisfy your hunger. I was intrugued by that article because it seems to contradict the commonly accepted assumption that overweightness is caused by low-fat diets. The abstract says that the 27 subjects were "healthy", but doesn't say whether they are overweight or not. Perhaps (and I say *perhaps*, because I haven't read the article) the reason is there. Best wishes, Jean-Louis [log in to unmask]