What Is Vitamin E Good For? We Found Out

"Vitamin E acts as an antioxidant that protects cells from free radicals," Yule says. "Free radicals can cause cellular damage that is associated with several chronic diseases." Think cancer, asthma, or dementia. Basically, vitamin E puts up a fight to keep these rogue molecules at bay. Shout out to vitamin E for being your own personal bodyguard against chronic illness.

Looking to make sure you're in top germ-fighting shape? "Vitamin E is involved in helping the immune system to function," says Yule. According to the Cleveland Clinic, it's especially talented at helping you ward off infection. A study of 32 healthy elderly people published in the American Journal of Clinical Nutrition showed increased immune function when they took vitamin E supplements, at least in the short term.

This little vitamin plays a significant role in helping to dilate blood vessels, Yule says, a.k.a. it makes your blood flow more smoothly and reduces your blood pressure. According to the National Institutes of Health Office of Dietary Supplements, it does this by blocking the metabolism of arachidonic acid, which increases prostacyclin, which increases vasodilation. But good news: You don't have to remember any of that in order for it to work in your body.

Yep, you read that right. "Vitamin E helps maintain eye health," says Mascha Davis, a registered dietitian nutritionist in Culver City, California. For starters, it's an antioxidant as we mentioned, and free radicals can be linked to eye damage. But some studies, including a meta-analysis published in Public Health Nutrition that looked at both dietary and supplemental vitamin E, suggest that age-related cataracts may also be reduced in patients with higher vitamin E levels. The jury is still out, though, so for now, just continue to eat your peanut butter.

An oral vitamin E supplement — when paired with vitamin C — seems to help protect skin from DNA damage due to sun exposure, according to a few small studies (research in the Journal of Investigative Dermatology followed 18 people, a study in the Journal of the American Academy of Dermatology followed 10 people). But that doesn't mean it's a substitute for sunscreen. The effect appears to be modest, according to the Linus Paul Institute at Oregon State University.

Fun fact: Vitamin E was initially discovered when scientists were feeding rats a fat-based diet, and while they would grow, the female rats couldn't take a pregnancy to term. As the scientists experimented with adding lettuce and wheat germ to their diets, they were able to stay pregnant. So the fact that vitamin E is absolutely necessary for reproduction is one of the first-known facts about the vitamin. But it's not something you need to worry about — the World Health Organization says there's no reason for pregnant mothers to supplement with vitamin E. We're getting plenty.

For people with Cowden Syndrome, which is a disease that causes numerous benign growths in the body and also raises the risk for malignancies, vitamin E could reduce their cancer risk, a lab study from the Cleveland Clinic suggests. A mice study linked high-dose vitamin E supplements to an increased lung cancer risk, which is, of course, bad news — but the Cowden Syndrome study specifically used a more moderate dose (400 mg) and found that risk rates stayed stable. But it's still early, and more research is necessary.