Osteoporosis and low bone mineral density affect millions of Americans. The majority of adults in North America have insufficient intake of vitamin D and calcium along with inadequate exercise. Physicians are aware that vitamin D, calcium and exercise are essential for maintenance of bone health. Physicians are less likely to be aware that dietary insufficiencies of magnesium, silicon, Vitamin K, and boron are also widely prevalent, and each of these essential nutrients is an important contributor to bone health. In addition, specific nutritional factors may improve calcium metabolism and bone formation. It is the authors' opinion that nutritional supplements should attempt to provide ample, but not excessive, amounts of factors that are frequently insufficient in the typical American diet.In contrast to dietary insufficiencies, several nutrients that support bone health are readily available in the average American diet. These include zinc, manganese, and copper which may have adverse effects at higher levels of intake. Some multivitamins and bone support products provide additional quantities of nutrients that may be unnecessary or potentially harmful.The purpose of this paper is to identify specific nutritional components of bone health, the effects on bone, the level of availability in the average American diet, and the implications of supplementation for each nutritional component. A summary of recommended dietary supplementation is included.

We studied the effect of boron supplement on experimental osteopenia caused by strenuous exercise in 93- d-old female Wistar rats. A control group of 15 rats was not manipulated. The exercise group of 30 rats was divided into 2 groups of 15 rats each, one that was fed a diet supplemented with 50 mg/kg of boron in the form of Na(2)B(4)O(7), and other that, did not receive a boron supplement. The length and weight were determined in the femur and fifth lumbar vertebra and the bone mineral content and density were assessed through densitometry, and trabecular bone volume, trabecular number, trabecular thickness, and trabecular separation with histomorphometry. The femur length and weight, and vertebra weight, and femur and vertebra bone mineral content and density were significantly lower and the trabecular separation was higher in the exercise group than in the others (p<0.005 in all). The femur weight, bone mineral content and density, trabecular bone volume and trabecular thickness, were significantly higher in the exercise plus boron group (p<0.005 to 0.0001). It was concluded that boron preserves bone mass in rats that have been exposed to intense exercise.