"There are at least thirty-seven individual substances essential for a complete diet. These consist of amino-acids (derived from proteins), linoleic acid, dextrose, minerals and vitamins. An adequate supply of all these substances is absolutely essential for life." The foregoing significant statement was made by Prof. E. V. McCollum of Johns Hopkins University at an interesting conference of nutritionists held in New York City, on April 16, 1932.
During the past ten years the world has become vitamin conscious. Much has been said and written in regard to vitamins, and perhaps no one vitamin has been singled out for such marked attention as has vitamin D.
At the meeting mentioned particular attention was given to a thorough discussion of present day knowledge regarding this vitamin. Among those participating in the discussion were Profs. Lafayette B. Mendel and Grover Powers of Yale University, Profs. E. A. Park and E. V. McCollum of