INVESTIGATIONS OF ZINC IN TASTE PERCEPTION, ADOLESCENT GROWTH AND ZINC/FAT INTERRELATIONSHIPS

A three-part project investigated the role of zinc in taste perception, zinc/fat interrelationships and adolescent growth. Two twenty-five day paired feeding animal studies were conducted to investigate the response of zinc-deficient rats to a choice of quinine sulfate solution and deionized distilled water or sodium chloride and distilled water. The disappearance of zinc from liver, kidney, brain, tongue and salivary glands was also investigated under zinc-deficient and zinc-adequate conditions in one of the studies. No difference was found between zinc-deficient and zinc-adequate rats in taste preference for quinine sulfate, but an increase in taste preference for sodium chloride in zinc-deficient animals was found. Significantly higher tissue zinc contents of kidney, brain and parotid salivary glands were seen in zinc-adequate compared to zinc-deficient rats at the end of the study. Diets containing two levels of fat and zinc were fed to twelve adolescents during a two week controlled feeding study. Results suggested that higher levels of dietary fat may impair zinc absorption and therefore affect zinc nutritional status over time. Zinc intakes of twenty-two adolescent males and females were compared with anthropometric measurements and selected biochemical parameters in a longitudinal study. Mean zinc intakes for males and females were well below the current recommended daily intake but there was no evidence that either growth or biochemical parameters were affected by the low zinc intakes in these adolescent subjects