Ask the doctor: Understanding the value of multivitamins

Now the complicated part: do vitamin pills improve our health? There have been many studies of many different vitamin supplements. In my judgment, what the studies published so far say is that multivitamin pills do not provide benefits, but (taken as directed) they also don't put you at risk. There are some exceptions. Women who might become pregnant should take at least 400 micrograms of folic acid per day, which protects against birth defects. Older adults should get the equivalent of at least 800 units daily of vitamin D, in food or pill form, to protect against bone thinning (osteoporosis). There are some people who may benefit from a daily multivitamin: people who suffer from conditions of the stomach and intestine that make it harder to digest vitamins in foods, people who abuse alcohol, and people who eat a vegan diet (which is low in some vitamins). Finally, there are people who are born with conditions that can cause a specific vitamin deficiency. I am one of them. I inherited a condition that causes low levels of certain B vitamins in my body, so I take a B vitamin supplement daily (not a multivitamin pill).