ABSTRACT
The physiological influence of dietary boron is typically more pronounced during concurrent nutritional insult, especially vitamin D deficiency. Dietary boron influences mineral metabolism through uncharacterized mechanisms. In the vitamin D-deficient rat, low dietary boron decreases the apparent absorption and retention of calcium and phosphorus and increases femur magnesium concentrations. Dietary boron deprivation markedly increases plasma insulin concentrations in the vitamin D-deprived rat and also increases peak pancreatic insulin secretion from isolated, perfused chick pancreata by nearly 75%. Plasma triglyceride concentrations, depressed in the vitamin D-deficient, boron-deprived chick, are increased by supplemental boron. Boron is unequally distributed within Angiospermae, the class of plants most often utilized in animal or human diets. Most species within the subclass Dicotyledoneae, which includes nuts, fruits, vegetables, tubers, and legumes, have a much higher concentration of boron than do species in the subclass Monocotyledoneae, which includes the gramineous grain crops.
