Dietary zinc intake and its effects on zinc nutrition in healthy Japanese living in the central area of Japan

In the present study, we first examined the dietary zinc intake from food groups
in 109 healthy Japanese (24-82 years old, 45 male and 64 female) by means of the 72-h recall
method. We then used the ratio of apo/holo-activities of angiotensin converting enzyme
(ACE ratio) that is a more sensitive index of zinc nutrition than zinc concentration
in the serum and examined the correlation between their zinc intake and ACE ratio. Dietary
zinc intake in healthy Japanese was maximal from rice and rice products. There
were significant inverse correlations between the ACE ratio and dietary zinc intake
from rice and rice products and shellfish, and a significant positive correlation between
ACE ratio and dietary zinc intake from other beans and bean processed foods. On the
other hand, there were no significant correlations between serum zinc concentrations
and dietary zinc intake from any food group except processed fish. These findings suggested
that rice is a major source of dietary zinc intake in healthy Japanese. It is also
suggested that shellfish also has a major impact on zinc nutrition, although dietary zinc
intake from this source is minimal. Since beans contain phytic acid, which inhibits the
absorption of dietary zinc, it is suggested that intake of beans causes impairment of zinc
nutrition.

The journal of medical investigation : http://medical.med.tokushima-u.ac.jp/jmi/index.html