People can experience hair loss for numerous reasons including genetics, medications, medical conditions and poor nutrition. Some people that try to do something right for their bodies may actually being doing something bad for their hair if they overdo it with certain vitamins and minerals. If you take supplements, it's important to follow guidelines for safe amounts.
Vitamin A is a fat-soluble vitamin, which means excess amounts are stored in the body for later use. The vitamin helps prevent night blindness and promotes healthy eye function. It also keeps skin, hair and nails healthy and helps ward off bacterial infections, according to the McKinley Health Center at the University of Illinois at Urbana-Chicago. HairLossLibrary.com reports that if you're not getting enough vitamin A, it could lead to hair loss. However, if you get too much vitamin A, that can cause hair loss. The recommended intake of vitamin A varies depending on your age and gender and whether you're pregnant or nursing.
Zinc is another supplement that can be both good and bad when it comes to the hair. Like vitamin A, if you don't get enough zinc, it may contribute to hair loss. The Nutritional Supplements Health Guide reports that too much zinc may contribute to hair loss, too. Zinc is a trace mineral the body uses for functions such as cell reproduction, hormonal balance, protein synthesis and the proper absorption of vitamins.
Selenium is another trace mineral found in the body. The National Institutes of Health reports that selenium is essential to good health, but you only need a small amount to make the selenoproteins the body uses to help prevent cellular damage from free radicals, regulate thyroid function and help the immune system.The NIH reports that high levels of selenium in the blood can lead to hair loss, but it notes that selenium toxicity is rare in the United States. It does warn that Brazil nuts have an unusually high amount of the mineral and should be eaten only occasionally.
In addition to dietary supplements, there are a number of medications that may contribute to hair loss. According to MayoClinic.com, some drugs used to treat gout, arthritis, depression, high blood pressure and heart problems have been linked to hair loss. Some women taking birth control pills may also experience hair loss.