Moreover, the vitamin helps your hair, nails and skin remain healthy. You can find B12 in four chemical compounds: methylcobalamin, hydroxocobalamin, adenosylcobalamin and cyanocobalamin.

Allergic reactions to vitamin B12 are rare, but real. The reason may sound strange, but it's true - an allergy to cobalt.

Among the most popular vitamins touted on the labels of such drinks is vitamin B12 – a nutrient known to help with energy, but usually not in the way the industry advertises. Start the day smarter.

Dear Doctors: I was surprised when a blood test at my annual checkup found I’m low in B vitamins, especially B12. My doctor gave me a shot, and the fatigue that I had been feeling went away. Why is ...