A number of years ago, a group of French doctors tested for intolerance to milk fat. They found that 9 of the 100 people in their test group suffered symptoms when exposed to milk fat but not when exposed to milk sugar (lactose). They did the experiment in the first place because, they said, the French, as well as the Spanish and Italians, find skimmed milk more "digestible" than regular milk. Unfortunately, I do not know of a single follow up experiment in all the years since. Steve Carper