若年成人女子における潜在的亜鉛欠乏と塩味に対する味覚

抄録

Forty healthy female college students underwent gustatory function tests for salt (discrimination of salt concentration, salt taste threshold), biochemical parameter measurements (plasma Zn, plasma Na, plasma retinol, plasma retinol-binding protein (RBP)) and a five-day dietary consumption survey. In the tests, performed six times, individuals, rate of correct discrimination (RCD) between 0.6% and 0.7% NaCl concentration was 51.2+28.7%. Only eleven (28%) subjects were able to make a correct discrimination. No significant association was found between the RCD and either the detection or recognition threshold for salt. Plasma Zn, retinol and RBP levels were lower in the present subjects than in our previous studies. Plasma Zn level in 20% of the subjects was lower than 0.7 μg/ml. Correlations among plasma Zn, retinol and RBP were positively significant. From these associations and the finding that Zn is indispensable for the biosynthesis of RBP, it can be postulated that Zn influences vitamin A metabolism. These subjects showed low energy and nutrient intake (per kg body weight) levels except for protein. There was a significant correlation between Zn intake (per kg body weight) and the plasma Zn level. The RCD was correlated positively with plasma Zn. Although the level of significance did not exceed 0.05 (r=0.282, p=0.078), this tendency indicates that the plasma Zn level is related to RCD. There was a significant difference in plasma Zn level between the high and low RCD groups. With regard to the RCD, only the plasma Zn level showed a marginally significant partial regression coefficient (p=0.096) in multiple regression analysis. Thus, it was suggested that the plasma Zn level might have influenced the discrimination of salt concentration.