Q: When my mom used to feel weak and tired, her GP would give her a B-12 shot and she said she felt better the same day. We suspected that was a 'placebo effect,' but now I wonder if B-12 could help my own low energy. My last blood test was normal. - Maggie

A: Symptoms of vitamin B-12 deficiency often manifest months or years before B-12 blood tests become abnormal... And although the practice of administering vitamin B-12 injections has fallen out of favor, modern medical science now understands why B-12 supplementation makes people feel better... [more]