RELATION OF NUTRITION TO BONE LEAD AND BLOOD LEAD LEVELS IN MIDDLE-AGED TO ELDERLY MEN - THE NORMATIVE AGING STUDY

The relations of nutritional factors to lead accumulation in the body were examined cross-sectionally among 747 men aged 49-93 years (mean 6 7 years) in the Normative Aging Study in 1991-1995, Means (standard de viations) for blood lead, tibia lead, and patella lead were 6.2 (4.1) mu g/dl, 21.9 (13.3) mu g/g, and 32.0 (19.5) mu g/g, respectively. In multiple regression models adjusting for age, education level, smoking , and alcohol consumption, men in the lowest quintile of total dietary intake levels of vitamin D (including vitamin supplements) (<179 IU/d ay) had mean tibia and patella lead levels 5.6 mu g/g and 6.0 mu g/g h igher than men with intake in the highest quintile (greater than or eq ual to 589 IU/day). Higher calcium intake was associated with lower bo ne lead levels, but this relation became insignificant when adjustment was made for vitamin D. The authors also observed inverse association s of blood lead levels with total dietary intake of vitamin C and iron . When analyses were controlled for patella lead, age, smoking, and al cohol consumption, men in the lowest vitamin C intake quintile (<109 m g/day) had a mean blood lead level 1.7 mu g/dl higher than men in the highest quintile (greater than or equal to 339 mg/day), while men in t he lowest iron intake quintile (<10.9 mg/day) had a mean blood lead le vel 1.1 mu g/dl higher than men in the highest quintile (greater than or equal to 23.5 mg/day). This study suggests that low dietary intake of vitamin D may increase lead accumulation in bones, while lower diet ary intake of vitamin C and iron may increase lead levels in the blood .