Abstract
Lard when added to synthetic rachitogenic diets in amounts varying from 5 to 25% had definite antirachitic properties which were not associated with the non-saponifiable fraction. The lard increased calcification on diets containing excessive (1.1%) or moderate (0.38%) amounts of calcium. The lard was effective when added on either a weight or calorie basis. The effect of the lard was less pronounced on diets very low in phosphorus (0.02%) than on diets higher in phosphorus (0.09%). Oleic acid also increased calcification but sodium oleate and the calcium soaps of lard showed no antirachitic action. These data are discussed in relation to the various theories advanced to explain the action of fats in favorably influencing calcium and phosphorus utilization. With the exception of the effect on the acidity of the intestinal tract these theories are apparently disproved by the data here reported.