A group of compounds that help with vision, bone growth, reproduction, cell division, and helping cells become part of the brain, muscle, lungs, blood and other tissue. Vitamin A also helps regulate your immune system to ward off diseases.

Vitamin A found in foods that come from animals is called "preformed vitamin A." It is absorbed in the form of retinol, and comes from liver, whole milk and other fortified foods.

Vitamin A also is found in colorful fruits and vegetables, which is called "provitamin A carotenoid." Beta-carotene is one of the better known carotenoids.

Source: U.S. Office of Dietary Supplements.

Water-soluble vitamin C is neither made by humans nor stored for long in our systems. Vitamin C, like the water-soluble B vitamins, moves quickly through our bloodstreams and excreted through urine. For this reason, we need to constantly replenish our vitamin C supply by consuming citrus fruits, strawberries, broccoli, peppers and spinach.

Supplements and multivitamins can also increase intake, but there's no need to overload on this well-known antioxidant, as recommended daily intake varies from person to person. Vitamin C protects cells from free radical damage and helps strengthen weakened immune systems.

It also helps increase iron absorption and bioavailability. For example, if you add orange slices to your spinach salad, the vitamin C will help release the iron from the spinach absorbed in the body.

Source: Nubella

An essential component of proteins involved in oxygen transport, regulation of cell growth, and cells becoming part of the brain, muscle, lungs, blood and other tissue. Iron deficiency limits the delivery of oxygen to your cells, resulting in fatigue, poor work performance and decreased immunity. Excessive amounts of iron can result in toxicity and even death.

Almost two-thirds of the iron in your body is found in hemoglobin, the protein in your red blood cells that carries oxygen to tissues.

Red meats, fish, poultry, lentils, beans, and iron-enriched and iron-fortified foods provide dietary iron.

Source: U.S. Office of Dietary Supplements

An essential mineral for strong bones and teeth. Calcium is found in dairy products, many vegetables, including broccoli and collards, and in some nuts and seafood. Most Americans get less than half the calcium they need so that when they reach 30, their bones begin to lose more mass than they create.

You can prevent osteoporosis, or "brittle bones," by adding more calcium to your diet from foods and supplements, in addition to exercising regularly, especially engaging in weight-bearing activities like running, tennis or soccer.

Source: Nubella

Otherwise known as vitamin B-2, an essential element for body growth and production of red blood cells, and releasing energy from carbohydrates. Major sources include lean meats, eggs, legumes, nuts, green leafy vegetables and dairy products. Breads and cereals are fortified with riboflavin.

Source: U.S. National Library of Medicine

A water-soluable vitamin that helps with protein metabolism, red blood cell metabolism, functioning of the immune and nervous systems, and conversion of the amino acid tryptophan to niacin. The body needs Vitamin B6 to make the blood's hemoglobin.

The vitamin also helps maintain blood glucose level within a normal range.

Fortified cereals, beans, meat, poultry, fish and some fruits and vegetables are major sources of vitamin B6.

U.S. Office of Dietary Supplements

A mineral the body uses to digest protein and sugars. It also helps the body absorb calcium. People who do not have enough phosphorus in their bodies may lose weight, feel weak, and have growth problems, particularly with bones.

Foods high in phosphorus include milk, cheese, meat, egg yolks, whole grains, peas and nuts.

People who drink large amounts of alcohol often have low phosphorus.

Source: Nubella

An important mineral for building bones, protein and teeth. It also helps in muscle contraction and nerve function and in fighting infection. Sources of magnesium include nuts, whole grains, dark green vegetables, seafood and cocoa. Magnesium is also available in supplements.

Source: Nubella

An essential mineral that stimulates the activity of about 100 enzymes that promote a healthy immune system, wound healing, senses of taste and smell, and DNA synthesis. Zinc also supports normal growth and development during pregnancy, childhood and adolescence.

Major sources include oysters, red meat, poultry, beans, nuts, certain seafood, whole grains, fortified cereals, and dairy products.

Source: U.S. Office of Dietary Supplements

Otherwise known as folic acid, one of the B vitamins, an important mineral for normal development of a fetus, production of red and white blood cells and platelets, formation of DNA in cells, and growth. Folic acid is found in liver, kidney, yeast, bananas, oranges, leafy vegetables, eggs, whole-wheat bread, lima beans and milk. Supplements of folic acid before and during pregnancy can reduce the chance of having a baby with birth defects.

Source: Nubella

Known as vitamin B-3, niacin helps in the functioning of the digestive system, skin and nerves, and is important for the conversion of food to energy. Major sources include dairy products, poultry, fish, lean meats, nuts and eggs. Other sources include legumes and enriched breads and cereals.

Source: U.S. National Library of Medicine

Otherwise known as vitamin B-1, which helps the body's cells convert carbohydrates into energy. It is essential for the functioning of your heart, muscles and nervous system.

Thiamine is found in fortified breads, cereals, pasta, whole grains, lean meats, fish, dried beans, peas and soybeans. When consumed in large amounts, dairy products, fish and vegetables also become significant sources of thiamine.

Source: U.S. National Library of Medicine