With entire stores devoted to selling multi-vitamins and supplements, the headlines coming out about multi-vitamins seem to be conflicted. One day, the media can report that they are essential to preventing disease and the next day reports state these vitamins are doing more harm than good.
For example, a large observational study by the Iowa Women’s Health Study followed a group of women for 19 years and found that those women who reported taking a daily multi-vitamin were actually 6% more likely to diet than those who did not report taking a daily multi-vitamin. Researchers have hypothesized that users of multi-vitamins may be healthier because they tend to have a healthier lifestyle and diets, which lower their risk of disease and called for a randomized study to look at the cause and effect relationship of the Iowa study.
The randomized study, called the Physicians’ Health Study II, followed 14,000 men who took either Centrum Silver or a placebo everyday for 11 years and found that the risk of dying was not significant between the two groups. The study also found that taking a multi-vitamin had no effect on the risk of developing heart disease, stroke or cancer. This find has been consistently proved in other studies as well, including the Multiethnic Cohort Study and Women’s Health Iniative cohort.
So when is it worth it to take a multi-vitamin? The answer, in short, is when it will suppliement nutrients that you may not be getting from your regular diet. For example, between 7-16% of women aged 12-49 are iron deficient and may benefit from multis that contain the recommended daily value of 18 miligrams. Additionally, persons age 50+ generally get vitamin B-12 from either fortified foods or supplements, with the recommended daily amount being 2.4 micrograms.
The important takeaway from the multi-vitamin argument is to not rely on them to keep you healthy! While multi-vitamins may be beneficial for those who have a nutrient deficiency, it is important to keep in mind that research shows that these multi-vitamins will not reduce the risk of disease and that they are not a subtsitute for a healthly lifestyle.