The supplementary value of the banana in institution diets: II. Capillary resistance and reduced ascorbic acid in the blood plasma

Abstract

<h2>Summary</h2> This study, as reported in this and Part I, affords a small contribution to the problem of optimum versus adequate nutrition. It reports the results of supplementing the diet of approximately 100 boys living in an institution with two to three bananas daily over the period of a school year. The usual diet of the institution would be considered adequate in that it measured up to all minimum dietary standards which have been proposed. Nevertheless, it appeared to be susceptible of improvement, for the boys receiving the supplement showed consistently better growth and development by every measure of physical status which was applied than did the control boys who did not receive it. This was evidenced for growth in height, weight, arm girth, and subcutaneous tissue, for ossification of the carpal bones, and for the two measures of vitamin C stores used, namely, capillary resistance and reduced ascorbic acid in the blood plasma. The most significant differences were those for blood ascorbic acid. The experimental boys averaged 0.20 mg. per 100 c.c. of plasma higher than the control boys; this difference is six times its probable error and therefore significant. These results indicate that the allowances for the various dietary essentials for boys of the ages here studied should approach the higher rather than the minimum standards which have heretofore been proposed, in particular for vitamin C. Taking into consideration the findings of this study, previously proposedstandards, and the small amount of experimental data available on food requirements, tentative allowances are proposed as reasonable ones to use for boys 10 to 12 years of age until more precise data on the needs for these years are obtained.