The Brains of animals consist largely of a fatty matter containing cholesterin, and lecithin, the latter element being comparatively rich in phosphorus. Dr. Salmon (in 1696) directed that "a ram's Brain fried, and a cake made of it with sheep suet, cinnamon, and nutmeg, is good against the lethargie, and other drowsie diseases."But Dr. Yeo now admonishes that "the large percentage of fat contained in the Brains of animals renders them difficult of use as food by weak stomachs."Nevertheless, ordinarily, owing to its soft consistency, the Brain is more readily digested than any other animal part; but, unfortunately, it is very imperfectly absorbed. 43 per cent of it being voided in the excrement from the bowels. Therefore, in spite of its easy digestibility, it cannot be regarded as a valuable food for invalids. Neither, as he supposes, is it in any sense specially fitted for "making Brains." "Some persons do fancy," said Lemery (1674), as an ancient writer has told, "that rabbit's Brains weaken the memory, because this animal cannot for a moment after retain in mind the toils laid for her, and that she had just escaped; but this conjecture being founded on a weak foundation, I shall not stop here, and go about to confute it".

To blanch (calf's) Brains, put them into a basin, with some cold, well-salted water to wash them; then strain, and rinse them in two or three other waters; put them into a stewpan, with a sliced onion, a small bunch of herbs, a few black and white peppercorns, and a teaspoonful of lemon-juice; bring them to the boil, then leave them in the liquid until cold; remove the outside of the Brains, and cut up the inside white part into small dice, and use them for the table. The calf's Brain is tasteless of itself, but palatable with a white sauce, and absolutely tender; when fried it evolves a very fine osmazome flavour, superior to that of any meat, or game; but the least over-frying is destructive of this flavour. Ox Brain is not eatable. Brain substance, or its medicinal principle - "cerebrin "- got from the grey matter of calves', and sheeps' Brains, is used remedially by modern physicians against some forms of disease in the human brain. Concerning the dictum which has obtained a widespread belief as to the functions of the human brain, that "without phosphorus there is no thought,"this is only true in the sense that the brain contains phosphorus as one of its constituents; and, unless we use the brain, thought, it would seem, is unthinkable.

But the fact has never been shown that an increased supply of phosphorus in the food is especially favourable to mental effort. "It comes to this on the whole," says Dr. Hutchison, "that the digestibility of a food is of far greater concern to a brain-worker than its chemical composition".

Furthermore, mental work influences the amount, and nature of the food which thereby becomes needed, in a different way from muscular labour. Brain work does not appreciably increase bodily waste at all, a fact which should be realized, and acted upon as regards the daily diet. "Mark this," wrote Oliver Wendell Holmes, "that I am going to say, for it is as good as a working-man's professional advice, and costs you nothing: It is better to lose a pint of blood from your veins than to have your nerves tapped. Nobody measures your nerve-force as it runs away, nor bandages your brain and marrow after the operation."As to special Brain nutriments, they do not exist. Small, and rather frequent meals of easily-digested food make up the ideal to aim at, it being remembered that brain work is usually also sedentary work. The reduction in the diet for mental work should probably affect the starches, sweets, and fats, more than the animal foods, fish, fowl, meat, eggs, and milk.