The nutritional status of zinc in the elderly and the effect of zinc supplementation on this nutritional status were studied. The relationship was examined between the serum zinc concentration and food intake of healthy elderly persons (n=11; average age, 80; Female/Male=6/5) admitted to a health facility for six months, to whom an oral zinc supplement had been administered for the last three months (8mg/day for one month, and 16mg/day for the following two months).
The daily oral intake of zinc was lower than the dietary reference intake (RDA: recommended dietary allowance) of zinc for the first three months. Daily oral zinc supplementation during the last three months induced no significant increase in the serum zinc concentration, although the zinc intake exceeded the dietary reference intake (RDA).
A positive correlation was apparent between the serum zinc concentration and the daily intake of energy or protein, particularly during the last three months, and also between the same zinc concentration data and the serum albumin or iron concentration. This correlation suggests that, in ensuring that the elderly maintain a suitable serum zinc concentration, it is important to consider the total nutritional status, including the intake of energy and proteins and the albumin levels, when providing dietary zinc supplementation.
