Molybdenum balance in healthy young Japanese women.

The absorption and balance of molybdenum (Mo) were examined in 43 healthy young Japanese women in four metabolic studies performed once a year from 2001 to 2004. In each year, an 18-d metabolic study, including two successive balance study sessions of 4 d, was designed and four kinds of dietary menus were supplied to the subjects periodically. Since the protein sources of the menus were specified in 2001-2003, and soybean products were poor in 2001 and 2002 and rich in the 2003, Mo intake in 2001 and 2002 was about 150microg/d while that in 2003 reached 318microg/d. In 2004, the protein sources were not specified and Mo intake was 217microg/d. This range of Mo intake overlapped that in the Japanese population. When the results of the four studies were pooled, Mo balance was calculated as 0.09+/-0.37microg/d/kg (mean+/-SD), and no significant relationship (r=0.142) was observed between the intake and balance. Between the apparent absorption (Y) and the intake (X), a significant (r=0.988, p<0.001) positive linear regression (Y=0.927X-0.523) was observed. Similarly, a significant (r=0.960, p<0.001) positive linear regression was observed between Mo intake and urinary excretion. These results indicate that more than 90% of Mo contained in a routine dietary menu is absorbed, most of Mo absorbed is excreted in urine, and Mo balance is in equilibrium in the general Japanese population.