Cobalt

Other Name(s):

cobalamin, cyanocobalamin, hydroxycobalamin

General Description:

Cobalt is a mineral required by the body for blood formation. In elemental form, it is a hard gray metal. Its only well-recognized function is as a component of vitamin B-12, a vitamin essential for producing red blood cells and maintaining the nervous system.

Cobalt, present in the body only in the form of vitamin B-12, is essential to erythropoiesis, or production of red blood cells.

Cobalt serves some of the same purposes as manganese and zinc. It can replace manganese in the activation of several enzymes (biochemical reaction activators) and it can replace zinc in some enzymes.

Cobalt also participates in the biotin-dependent Krebs-cycle, the process that the body uses to break down sugars into energy.

Medically Valid Uses:

Cobalt, as part of vitamin B-12, prevents pernicious anemia. Vitamin B-12 is also essential for maintaining the nervous system.

Unsubstantiated Claims:

Please note that this section reports on claims that have NOT yet been substantiated through scientific studies.

Cobalt may help produce a feeling of well-being. It is claimed to help increase energy and reduce fatigue.

Recommended Intake:

When present in nutritional supplements, cobalt is usually measured in micrograms (mcg). The average adult intake of cobalt is 5 to 8 mcg per day. No safe Recommended Dietary Allowance (RDA) for cobalt has been established yet.

Trace amounts of cobalt are present in most foods. Foods high in vitamin B-12 are the only source of cobalt actively used by the body. Foods containing cobalt include meat, milk, eggs, figs and cabbage.

Cobalt supplements are best taken in the form of vitamin B-12. Cobalt supplements may be necessary for diets deficient in animal proteins, milk or dairy products, or for vegan (strict vegetarian) diets. Breast-fed infants of vegan-vegetarians may also need supplements. However, it is best to ensure that the mother is adequately supplemented with B-12. This ensures that the infant gets sufficient B-12 in the breast milk.

Absorption problems of the cobalt-containing vitamin B-12 also create a need for supplements. People over 65 years old frequently have decreased absorption of vitamin B-12 and decreased serum levels. Other problems leading to poor absorption are intestinal malabsorption (gluten-induced enteropathy, celiac disease or sprue), gastrectomy or fish tapeworm infestation (Diphyllobothria latum).

Individuals with thalassemia, hypothyroidism (decreased thyroid function), liver disease or heavy alcohol use may need cobalt supplements in the form of vitamin B-12.

A cobalt deficiency is ultimately also a vitamin B-12 deficiency. Anemia, specifically pernicious anemia, is one of the obvious symptoms of a cobalt deficiency. Numbness, tingling and decreased nerve function occur in long-standing pernicious anemia.

Side Effects, Toxicity and Interactions:

Cobalt is toxic to the heart muscle and can result in toxic cardiomyopathy (heart muscle disease).

Polycythemia, an increase in red blood cells, may be a symptom of cobalt excess. Untreated polycythemia can result in congestive heart failure.

Excessive intake of cobalt may produce a goiter (enlargement of the thyroid gland) and reduce the activity of the thyroid. Cobalt may cause hyperglycemia (increased blood sugar) and result in damage to the alpha-cells of the pancreas.

There are no known contraindications to cobalt. However, since cobalt is an integral component of vitamin B-12, individuals with Leber's syndrome, a type of optic atrophy, should not take any nutritional supplements containing vitamin B-12 without first consulting their physician.

Women who are pregnant or breast-feeding should consult a physician before taking any mineral supplements.

There are no known significant food or drug interactions associated with cobalt.

Additional Information:

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References:

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10. Smolin LA, Grosvenor MB. Nutrition Science and Applications. 2nd ed. Sanders College Publishing; 1997.