Problems in Human Nutrition

Abstract

IN the acquirement of knowledge by the experimental method, with the attention to minute detail which accurate and successful work demands, it is sometimes useful to pause a while and raise the eyes from the task in hand, and to take a general survey of the field—what has already been accomplished and what still remains to be done. Some reflections on problems in nutrition are suggested by perusal of the thirteenth annual report of the Medical Research Council, more especially as one chapter of our knowledge of the elusive, but extremely important, accessory food factors appears closed, even though the next may be already partly written. The discovery that ergosterol is the precursor of vitamin D, and is converted into it on irradiation by ultra-violet light or by exposure to sunlight, has already been referred to in these columns (NATURE, vol. 120, p. 955; 1927): it is now possible for the first time to produce a vitamin from a pure chemical compound in the laboratory or even in the factory, so that an ample supply should be readily available for all.