Can You Take A Prenatal If You're Not Pregnant? What The Experts Say

Multivitamin supplements come with vitamins and mineral proportions tailored to the needs of many different people. You can find multivitamins and supplements if you're an athlete, a man over 50, or a woman trying to conceive. When it comes to the latter, prenatal vitamins stand out for having folic acid, which is a synthetic form of folate. Since folic acid helps prevent birth defects, women in their childbearing years who are hoping to conceive can benefit from 400 mcg a day (via GoodRx).

Prenatal vitamins are also higher in iron, which helps your body make the red blood cells that carry oxygen throughout your body. Pregnant women need 27 mg of iron a day, compared to men and postmenopausal women, who only need 8 mg — however, women in general need 18 mg if they get their period each month and lose iron through that blood (via Harvard School of Public Health). Some people believe that a beneficial side effect of taking prenatal vitamins is that they can help strengthen your nails and hair, but the Mayo Clinic says those claims lack evidence. 

Although you can take a prenatal if you're not pregnant, the excess iron and folic acid they contain might have unwanted side effects.

Your body needs red blood cells, but the individual cells only live between three and four months. Therefore, it's important for your body to continually make these red blood cells to help transport oxygen to your tissues. Iron helps your body make hemoglobin, which is a necessary protein to make red blood cells. If your body is low in iron, vitamin B12, or folic acid, you could develop anemia, with symptoms including headaches, problems focusing, or feeling weakness (via Penn Medicine). 

Prenatal vitamins have extra iron because people who are pregnant are at a greater risk of developing anemia, but it might sound logical to boost your iron intake to make sure your body makes enough red blood cells even if you aren't pregnant. However, if you're already getting enough iron from the food in your diet, an iron supplement could have some unpleasant side effects, like constipation or diarrhea, or other gastrointestinal side effects like nausea, vomiting, heartburn, indigestion, or abdominal bleeding. 

The excess iron in a prenatal vitamin might also have you experience mood changes, disruption in hormone levels, sensitivity to the sun, or itchy skin (via Discover).

Folate, which is the natural form of vitamin B9 found in food, also helps your body make red blood cells, but additionally, it helps with breaking down the nutrients in your food. If you can't get enough folate from your diet, you can supplement it with folic acid (via GoodRx). Some prenatal vitamins might have as much as 800 mcg of folic acid, which is often absorbed better by the body than folate. Because supplements aren't regulated by the Food & Drug Administration, it's possible that the prenatal vitamin could actually have up to 30% more folic acid: the upper limit of folic acid is 1,000 mcg (via Consumer Lab).

Although your body will get rid of excess folic acid, high doses of it can lead to problems with sleep or concentration, bloating, nausea, or irritability. If you're not pregnant and take a prenatal vitamin with excess folic acid, you might become less interested in sex (via Discover). Too much folic acid from a prenatal also might cover up a vitamin B12 deficiency. Therefore, it's best to skip taking a prenatal vitamin supplement if you're not pregnant unless it's recommended by your doctor (via Healthline).