This week, Dr. Michael Gilbreath with Hilton Head Gastroenterology talks vitamin supplements and if they're actually doing us any good.
Question. Recently, an article in the Annals of Internal Medicine titled, "Enough Is Enough: Stop Wasting Money on Vitamin and Mineral Supplements," concluded there is little evidence of vitamins' benefits, and some evidence they do harm. Should we throw out our daily multivitamins, keep buying them or does it not matter?
Answer. Some organic compounds required for health cannot be made by humans. Many people refer to these compounds by the historical term "vitamins." Since our bodies cannot make them in sufficient quantity, vitamins must be obtained from our diet. These compounds are unrelated to one another, so this is an unfortunately broad topic.
In this country, the government does not regulate food supplements (vitamins, minerals and herbs) so we're on our own when trying to decide if taking extra vitamins is beneficial or safe.
Several vitamins are classified as "water soluble" (B vitamins, folic acid and vitamin C) while others are classified as "fat soluble" (vitamins A, D, E and K). True vitamin deficiencies result in conditions that have been well described for many generations. In one example, scientists observed that soft bones and skeletal deformities, common in children, could be prevented with cod-liver oil. Today we know that the skeletal strengthening compound in cod-liver oil is "vitamin D."
Because each person's diet, state of health and access to wholesome foods differ, select people may benefit from vitamin supplementation. People who might be encouraged to supplement vitamins include those with restricted diets, someone with intestinal malabsorption and patients on dialysis.
Vitamin supplements are usually not needed for adults who eat a balanced diet and consume dairy products. A balanced diet with added fruits and vegetables also provides fiber and other essential nutrients. Finally, fruits and vegetables replace meat and animal fat, which many of us overconsume.
Checking blood levels of vitamins could be done if there's a suspicion of a specific deficiency. Vitamin B-12 might be checked in patients with anemia, mental decline or neurologic problems. Vitamin D levels are frequently checked in the evaluation of osteoporosis.
Many people take a multivitamin containing a daily allowance of individual vitamins; for many they are unnecessary, but probably safe.
Because particular vitamins in large doses can be harmful, high-dose single vitamin supplementation should only be used in specific situations. For example, vegans might need vitamin B-12.
Many physicians recommend vitamin D supplements for older Americans who are at risk of falling. I would take vitamin D if my levels were measured and found to be low.
Doctors who specialize in developmental disorders recommend folic acid in women who might become pregnant. It is well accepted that folic acid reduces neural tube defects in an embryo.
High doses of fat-soluble vitamins (A, E and K) can be dangerous. I never recommend taking fat soluble vitamins unless I'm treating a very specific condition. High doses of water soluble vitamins are probably safe but of doubtful benefit for most.
Other reported uses of vitamins are less well established. When in doubt ask your doctor about your individual concerns.
I try to eat a balanced diet, and I take no supplements at all. If I didn't have year-round access to fruits and vegetables, I'd consider a multivitamin. I would never take a high dose of any vitamin unless I had a specific medical condition that required it.