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 150 μg/d while that in 2003 reached 318 μg/d. In 2004, the protein sources were not specified and Mo intake was 217 μg/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±0.37 μg/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 = 0.927 X - 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.