Should you take a vitamin B12 supplement?

An estimated 3.2% of adults ages 50 or older have very low B₁₂ levels, and up to 20% may have borderline deficiency. Aging is often the cause. Other causes include taking heartburn medications; eating a diet that does not include animal products; weight loss surgery; or autoimmune diseases that attack the stomach lining or gastrointestinal tract. It’s a good idea for older adults to take a B₁₂ supplement of 2.8 micrograms daily to ward off B₁₂ deficiency. People who have very low levels of B₁₂ may need to take a much higher dose or get B₁₂ injections.