THE TOLERANCE OF MAN TO COLD AS AFFECTED BY DIETARY MODIFICATIONS: HIGH VERSUS LOW INTAKE OF CERTAIN WATER-SOLUBLE VITAMINS

Abstract

The effect of a diet containing borderline concns. of certain water-soluble vits. was compared to the same diet supplemented with these vits. on the ability of 12 young healthy [male] [male] to withstand repeated exposures of 8 hrs. duration either to intense cold ([long dash]20[degree]F.) with considerable protective clothing or to a cool environment (60[degree]F) with little protective clothing was studied. The imposed differences in vit. intake had no demonstrated effect on the tolerance to cold as measured by changes in rectal and mean skin temp., and in the performance of a series of psychomotor, perceptual, and intellective tests. A definite acclimatization to cold was demonstrated after exposure to [long dash]20[degree]F., for subsequent exposure to 60[degree]F. with little clothing induced a smaller decrement in rectal temp. than otherwise would have occurred. No significant increase of the excitability of the retino-eortical system as measured by the Critical Fusion Frequency of Flicker was observed as a result of a surplus of the water-soluble vitamins, although these vitamins very probably minimized the fatiguing effect of cold on the retino-cortical system. The authors concluded that the ability of [male] [male] to withstand repeated exposures to cooling environments cannot be appreciably enhanced by giving excessive amts. of certain water-soluble vitamins, and they suggest that the requirements of some of these vits. are considerably less than the recommended allowances of the Food and Nutrition Board of the National Research Council.