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What Is A LOOK AT THE EFFECTS AND COBALT? REGULATION OF THE MINERAL
Cobalt is a mineral that is present in animal systems predominantly as part of vitamin B12, which plays a key role in the production of DNA. It is a nutritionally required element with the lowest dietary requirement of all of the required trace minerals. The recommended daily allowance for humans is about 0.1 Âľg/day in the form of vitamin B121. The National Research Council, which determines daily requirements of nutrients for animals, has determined a dietary cobalt requirement of 0.5 to 1.1 mg/day in horses and 1.2 to 2.4 mg/ day for a cow, depending upon weight and metabolic state, with the recommended amount not to exceed 25 mg/kg of dry matter of feed or forage2. Cobalt concentrations in drinking water typically range from 0.1 to 5 ng/ml, and daily cobalt intake ranges from 11 to 580 Âľg/day in humans1,3. Legumes, like alfalfa and clover, are the principal sources of cobalt in the natural diet of horses, and there can be widely varied concentrations of cobalt in these forages across different geographical locations in the United States and internationally4,5. Deficient soils can result in profound deficiencies in cattle and sheep, resulting in anemia, weight loss and general poor body condition. Deficiencies in these species are likely under-identified but readily corrected by supplementation6. In contrast, deficiency has not been identified in horses. 40
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By Clara K. Fenger, DVM, PhD, DACVIM, and Peter J. Sacopulos, JD
Oral absorption of cobalt salts in humans varies depending on the dose, compound, nutritional status of the individual and proximity in time to a meal7. For example, in rodent studies, anywhere from 5 percent to 30 percent cobalt can be absorbed orally depending on the cobalt compound. Increasing the dose of cobalt does not tend to cause significant accumulation, as increasing doses result in a smaller proportion of the dose being absorbed. In humans, approximately 80 percent of cobalt is excreted in the urine and about 15 percent in the feces8. No studies evaluating the oral absorption of cobalt have been done in horses.
Why is cobalt used in athletes? Human recombinant erythropoietin (EPO) became available in the 1990s and rapidly became adopted into covert doping programs for human athletes. EPO stimulates the bone marrow to produce red blood cells, increasing the oxygen-carrying capacity of the blood. The ability to test for EPO was developed in the early 2000s, curbing its abuse, but it was pointed out in the medical literature9,10 that cobalt, originally used to increase human red blood cell counts in the treatment of anemia, also had the potential to be used and misused in athletics in much the same way as the administration of EPO. The potential illicit use of cobalt to improve athletic performance