"The following table shows that cottage cheese is much cheaper than most meats in furnishing protein for the diet. "For supplying protein, one pound of cottage cheese equals: 1.27 pounds sirloin steak. 1.09 pounds round steak. 1.37 pounds chuck rib beef. 1.52 pounds fowl. 1.46 pounds fresh ham. 1.44 pounds smoked ham. 1.58 pounds loin pork chop. 1.31 pounds hind leg of lamb. 1.37 pounds breast of veal. "In addition to protein, energy for performing body work must be furnished by food. As a source of energy also, cottage cheese is cheaper than most meats at present prices. The following table shows the comparison when energy is considered. "On the basis of energy supplied, one pound of cottage cheese equals: 8-1/3 ounces sirloin steak. 11¼ ounces round steak. 11¼ ounces chuck rib beef. 10¾ ounces fowl. 5½ ounces fresh ham. 5 ounces smoked ham. 6 ounces loin pork chop. 7-1/3 ounces hind leg of lamb. 12¾ ounces breast of veal." +335. Digestibility of cheese.+--Although it has been a staple food with many races for uncounted years, there is a widespread belief that cheese is suitable for use chiefly in small quantities as an accessory to the diet, and that in large quantities it is likely to produce physiological disturbances. The question of digestibility was made the subject of a special investigation by the United States Department of Agriculture.[147] Calorimeter experiments[148] were made to test the digestibility of several varieties of cheese and some of these varieties at various stages of ripening. All forms of cheese were found to be digested as completely as most of the usual forms of food. Approximately 90 per cent of the nitrogenous portion (casein) was retained in the body. Unripe cheese in these experiments was apparently digested as completely as the ripened forms. These experiments make clear the possibility of making cheese a more prominent article in the regular dietary than is usual in America. They especially point to the desirability of the use of the skim and partially skim cheeses, which as cheap sources of protein when properly combined with other foods, may be made to replace meats as a less costly source of proteins. Cheese is then to be classed with meat and eggs, not with condiments. An ounce of Cheddar[149] cheese roughly is equivalent to one egg, to a glass of milk, or to two ounces of meat. It is properly to be combined with bread, potatoes and other starchy foods, lacking in the fat in which the cheese is rich. These experiments included Roquefort, fresh-made and ripe Cheddar, Swiss, Camembert and Cottage cheese.