Harvard Health Letter

By the way, doctor: Should I stop taking these vitamins?

Q. In addition to a multivitamin, I have been taking vitamin B12 supplements (1,000 mcg) for a few years, hoping to increase my energy. My recent blood profile showed a high level of B12 (1,826 pg/ml). Should I stop taking B12? My energy is about the same.

A. Severe B12 deficiency usually occurs with a condition called pernicious anemia, an uncommon disorder that arises from the inability to absorb the vitamin from food because the stomach does not make enough intrinsic factor, a protein that facilitates B12 absorption.

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