If you caught the news last week about vitamin and mineral supplements being, well, pretty much worthless at best and harmful at worst, you may have had one of these reactions:
- “I don’t care what they say, I’m going to keep taking my vitamins!”
- “Good. I could never remember to take them, anyway. When I figure out what to do with those five Costco-sized bottles, I’ll have more room in my kitchen cabinets.”
- “Ha! I’ve been telling people for years that supplements are a waste of money!”
- “Oh no! I thought my vitamins were making me healthier…but what if I’ve damaged my health?”
The bottom line is this: If you are generally healthy, you don’t need to be taking supplements unless you have a known vitamin or mineral deficiency. If you’ve been taking supplements and your healthcare providers haven’t told you to take them to treat a specific health issue, then simply stopping (using up your current bottle if you can’t stand throwing them away) should be fine. Supplements are expensive: use the money you save to buy more fruits and vegetables, which are natural nutrient powerhouses.
Why do people take vitamins?
- Because they think they are “supposed to”
- Because they think it will prevent disease
- Because they think it will make up for a diet of cheeseburgers
Well, consider all three reasons invalidated. The headline-making study, published in the Annals of Internal Medicine, reviewed 26 studies that examined the benefits and harms of using vitamin and mineral supplements for prevention of cardiovascular disease, cancer, or premature death from all causes in healthy individuals who had no known nutritional deficiencies.
Of those 26 studies, 24 were randomized, controlled trials, which is pretty much the research gold standard. (Subjects in those studies would have taken either a supplement or a placebo, and they wouldn’t have know which they were taking.) The reviewers looked at studies of multivitamins as well as single and paired nutrients. These included several antioxidants (beta carotene, vitamins A, C and E, and selenium) plus folic acid, vitamin D, calcium, and vitamin D + calcium.
Basically, the review found no consistent evidence that supplements affected whether subjects developed cardiovascular disease, cancer or died prematurely of other causes. It also found no consistent evidence of harm, other than confirming that beta carotene supplements increases the risk of lung cancer and death in people at high risk for lung cancer (mainly smokers). Some studies found increased death rates from use of vitamins A and E.
What this comes down to is, in spite of the fact that the mechanics by which various vitamins and minerals have physiologic effects is well established, supplemental forms of these nutrients just don’t behave the way we would expect. The study’s authors said this may be because the way nutrients interact with the body is so complex that taking them in isolated form doesn’t have the same effect. Simply put, separate nutrients from the foods they are naturally found in, and you are doing yourself a disservice.
So, taking a multivitamin won’t prevent disease or make up for a diet of cheeseburgers, and unless you have a specific reason for taking supplements (see below for examples), there’s no more “supposed to.”
The study did not look at a few key groups:
- Pregnant women. I would argue that, due to the increased needs for certain nutrients during pregnancy (folic acid and iron in particular), a multivitamin is still a good idea during pregnancy and when planning for pregancy. That’s something to discuss with your healthcare provider.
- Individuals at high risk for or being treated for disease. However, in these cases, if there are specific nutrient needs, then throwing a multivitamin at them is probably not helpful. Again, this is where working closely with your healthcare team, which hopefully includes a dietitian, can optimize your nutritional status.
The one vitamin that on which the jury is still out is vitamin D. If you live in a northern climate (like Seattle), supplemental D is likely a good idea, in the darker half of the year, for sure. I take it, and my doctor tests my vitamin D levels every year. If you haven’t had yours tested, ask your doctor about it.
