Our Guide: What Do Vitamins and Minerals Do?

Nutrition facts photo by Yasmeen via Flickr/Creative Commons
Do you know what vitamin D does? How about magnesium? Dare we even ask about riboflavin?
As health knowledge becomes more widespread, most people now know they need to consume a variety of vitamins and minerals from their food—not supplements—but far fewer know why, or what those substances actually do for the body. Here, a cheat sheet to 17 common vitamins and minerals, from vitamin A to zinc.
1. Vitamin A
via University of Maryland Medical Center
What it does: Among its many functions, vitamin A aids in growth and bone formation, immune health, wound healing, and reproductive health.
Sources: Milk, eggs, leafy vegetables, fish, carrots, broccoli, cantaloupe, squash.
2. Vitamin B6
via Mayo Clinic
What it does: It helps form two chemicals, serotonin and norepinephrine, that send signals to the brain, as well as the protein layer that surrounds nerves.
Sources: Grains, carrots, spinach, peas, potatoes, dairy, eggs, fish.
3. Vitamin B12
via Harvard Health Publications
What it does: Vitamin B12 plays a role in building red blood cells, nerves, and DNA.
Sources: Fish, most meats, dairy.
4. Vitamin C
via Good Housekeeping
What it does: Vitamin C contributes to disease prevention, immune health, and the formation of healthy tissues.
Sources: Nearly all produce, but especially citrus fruits, peppers, strawberries, brussels sprouts, and cantaloupe.
5. Calcium
via Harvard School of Public Health
What it does: In addition to building bones and teeth, calcium helps clot blood, regulate heart rate, and send nerve impulses throughout the body.
Sources: Dairy, kale, collard greens, beans, legumes.
6. Vitamin D
via the Cleveland Clinic
What it does: It’s best known for keeping bones strong, but vitamin D has also been shown to prevent disease and ease depression.
Sources: Fish, cheese, egg yolks.
7. Vitamin E
via Berkeley Wellness
What it does: Though the extent of its effect is controversial, vitamin E has antioxidant properties, meaning it is linked to preventing conditions like cancer and heart disease.
Sources: Nuts, seeds, whole grains, leafy greens, broccoli, tomato sauce, red peppers, carrots, fish.
8. Folate
via Mayo Clinic
What it does: Folate allows cells to divide and forms DNA.
Sources: Leafy vegetables, okra, asparagus, bananas, melons, lemons, legumes, mushrooms, liver, orange juice, tomato juice.
9. Iodine
via National Institutes of Health
What it does: Iodine makes hormones that control metabolism.
Sources: Fish, dairy, produce, iodized salt.
10. Iron
via Berkeley Wellness
What it does: Iron distributes oxygen throughout the body.
Sources: Meat, fish, poultry.
11. Vitamin K
via University of Maryland Medical Center
What it does: It aids in blood clotting and bone health.
Sources: Liver, green tea, turnip greens, broccoli, kale, spinach, cabbage, asparagus, green lettuce.
12. Magnesium
via National Institutes of Health
What it does: Magnesium regulates muscle and nerve function, blood sugar and pressure, and the formation of proteins, bones, and DNA.
Sources: Legumes, nuts, seeds, whole grains, leafy greens, dairy.
13. Niacin
via University of Maryland Medical Center
What it does: Also known as vitamin B3, niacin keeps the liver, hair, skin, eyes, and nervous system healthy. It also converts carbohydrates into energy.
Sources: Beets, brewer’s yeast, beef liver and kidney, fish, sunflower seeds, peanuts.
14. Potassium
via U.S. National Library of Medicine
What it does: Potassium helps the body build proteins and muscles, convert carbohydrates into energy, regulate growth, and keep the heart’s electrical activity normal.
Sources: Meat, fish, soy, dairy, nuts, bananas, broccoli, peas, lima beans, tomatoes, potatoes, squash, citrus, cantaloupe, kiwi, prunes, apricots.
15. Riboflavin
via Mayo Clinic
What it does: Also known as vitamin B2, riboflavin is key to digestion and making oxygen available to the body.
Sources: Dairy, fish, meats, leafy vegetables, whole grains.
16. Thiamin
via National Institutes of Health
What it does: Also known as B1, thiamin turns food into energy.
Sources: Whole grains, pork, fish, legumes, seeds, nuts.
17. Zinc
via Oregon State University
What it does: Zinc helps build cell membranes and proteins, catalyze chemical reactions within the body, and regulate cell activity.
Sources: Oysters, red meat, poultry, beans, nuts, crab, lobster, whole grains, dairy.