BORON IN HUMAN AND ANIMAL NUTRITION

This review describes the findings from human and animal studies indic ating that B is a dynamic trace element which, in physiological amount s, can affect the metabolism or utilisation of numerous other substanc es involved in life processes including macrominerals, energy substrat es such as triglycerides and glucose, nitrogen containing substances s uch as amino acids and proteins, reactive oxygen species, and estrogen . Through these effects, B can affect the function or composition of s everal body systems, including the brain, skeleton and immune system, generally in a beneficial fashion. Moreover, homeostatic mechanisms ap parently exist for B because it is rapidly excreted in the urine, does not accumulate in tissues, and is maintained in a relatively narrow r ange of concentrations in blood of healthy individuals. Thus, even tho ugh B has not been conclusively established as essential because a bio chemical function for it has not been identified, its beneficial actio ns suggest that an intake of over 1 mg day(-1) (but probably not more than 13 mg day(-1)) is desirable; diets low in fruits, vegetables, leg umes and nuts may not provide this amount of B. Boron may be of more p ractical nutritional importance than currently acknowledged.