Dietary boron intakes of selected populations in the United States.

Knowledge of daily boron (B) intakes will assist researchers in establishing B requirements and elucidating the metabolic role of B in humans. B concentrations in commonly consumed foods were utilized to approximate the B intake of selected US populations. Triplicate food samples were digested at low temperatures with 16 M HNO3 and 30% H2O2, and analyzed by inductively coupled plasma spectroscopy (ICP). Milk and dairy products, juices, and beverages were the largest contributors to dietary B. Total B content of average daily diets ranged from 548 microg for toddlers (2 yr old) to 883 microg for mature males (60-65 yr old), excluding tap water contributions. Toddlers consumed 3.7 times more B than mature males when adjusted for body weight (body wt) and consumed the diet with the highest boron density (1.8 microg/kJ or 0.43 microg/kcal). Adolescent females consumed a diet with the lowest B density (1.12 microg/kJ or 0.26 microg/kcal). Food B concentrations applied to diet records (1020 microg/d) and ICP analysis of the corresponding food composites (1170 microg/d) were comparable (p < 0.05). Current estimations of B in US diets are consistent with reports in the literature stating that normal adult daily B intakes are approx 1 mg.