Having now considered the general principles involved in vitamine testing we may justly ask what information they have yielded us in regard to the distribution of the vitamines in nature. If we must include vitamines in our diets it is important to know how to select foods on this basis, hence a classification of them on the ground of vitamine distribution becomes essential. The newness of the subject and the limited tests that have been made as well as the uncertainty residing in the test results make any classifications presented more or less approximations but we present such attempts as have been made, with the understanding that these tabulations are merely guides and not quantitative measurements in the sense that tables giving calorie values of protein, fat and carbohydrate content are. The following table (1) has been freely copied from a report of the British Medical Research Committee to which acknowledgment is hereby given. TABLE 1 _Pages 50 and 61 of the British Medical Research Committee's report_ __________________________________________________________________________ | | | CLASSES OF FOODSTUFFS |VITAMINE "A"|VITAMINE "B"|VITAMINE "C" ___________________________________|____________|____________|____________ | | | _Fats and oils:_ | | | Butter . . . . . . . . . . . . | +++ | 0 | Cream . . . . . . . . . . . . . | ++ | 0 | Cod-liver oil . . . . . . . . . | +++ | 0 | Mutton and beef fat or suet . . | ++ | | Lard . . . . . . . . . . . . . | 0 | | Olive oil . . . . . . . . . . . | 0 | | Cotton seed oil . . . . . . . . | 0 | | Cocoanut oil . . . . . . . . . | 0 | | Cocoa-butter . . . . . . . . . | 0 | | Linseed oil . . . . . . . . . . | 0 | | Fish oil, whale oil, herring | | | oil, etc. . . . . . . . . . . | ++ | | Hardened fats (hydrogenated) | | | of animal or vegetable origin | 0 | | Margarine from animal fat . . . | In propor- | | | tion to | | | animal | | | fat used | | Margarine from vegetable fat | | | or lard . . . . . . . . . . . | 0 | | Nut butters . . . . . . . . . . | + | | _Meat, fish, etc.:_ | | | Lean meat (beef, mutton, etc.) | + | + | + Liver . . . . . . . . . . . . . | ++ | ++ | + Kidneys . . . . . . . . . .