ZINC-ABSORPTION IN HEALTHY ELDERLY HUMANS AND THE EFFECT OF DIET

Absorption of a zinc stable isotope was measured on two consecutive oc casions in nine young and eight elderly healthy men aged 24-40 and 70- 83 y, respectively. A zinc stable-isotope label (0.8 mg Zn-70) was add ed to a test meal of either high or low zinc bioavailability, dependin g mainly on phytic acid content. Zinc absorption from the high-bioavai lability test meal was not significantly different (P > 0.05) in the y oung (38.9 +/- 9.8%, xBAR +/- SD) and elderly (35.0 +/- 10.9%) subject s. Zinc absorption from the low-bioavailability test meal was 40% and 43% lower. at 23.4 +/- 10.2% and 19.8 +/- 6.1% in these young and elde rly men. respectively. Again, no significant effect of age was found. These results show that aging does not lead to nutritionally relevant changes in zinc absorption and in the effect of dietary inhibitors on zinc absorption. Thus, zinc absorption ability seems to be preserved i n healthy elderly people, at least until the age of 80 y.