Vitamin B-12 2000 mcg by Nature's Way

 What does Vitamin B12 do?

Vitamin B12 is is a water-soluble vitamin needed for normal nerve cell activity, DNA replication, and production of the mood-affecting substance SAMe (S-adenosyl-L-methionine). Vitamin B12 acts with folic acid and vitamin B6 to control homocysteine levels. An excess of homocysteine is associated with an increased risk of heart disease, stroke, and potentially other diseases such as osteoporosis and Alzheimer’s disease.

Vitamin B12 deficiency causes fatigue. Years ago, a small, double-blind trial reported that even some people who are not deficient in this vitamin had increased energy after vitamin B12 injections, compared with the effect of placebo injections.¹ In recent years, however, the relationship between B12 injections and the energy level of people who are not vitamin B12-deficient has been rarely studied. In a preliminary trial, 2,500–5,000 mcg of vitamin B12, given by injection every two to three days, led to improvement in 50–80% of a group of people with chronic fatigue syndrome (CFS), with most improvement appearing after several weeks of vitamin B12 shots.² The ability of vitamin B12 injections to help people with CFS remains unproven, however. People with CFS interested in considering a trial of vitamin B12 injections should consult a doctor. Oral or sublingual (administered under the tongue) B12 supplements are unlikely to obtain the same results as injectable B12, because the body’s ability to absorb large amounts is relatively poor.