Vitamins are substances that your body needs to grow, develop and function. There are 13 vitamins your body needs. They are vitamins A, C, D, E, K, and the B vitamins (thiamine riboflavin, niacin, pantothenic acid, biotin, B-6, B-12, and folate). Each vitamin has specific jobs. If you have low levels of certain vitamins, you may develop a deficiency disease. Vitamins A, D, E, and K are fat-soluble, which means they are absorbed into the body with fat and are stored in the liver.  The B vitamins and Vitamin C are water-soluble which means they are not stored in the body and need to be replaced every day.

 Let's start with vitamin A. Vitamin A is an antioxidant. Antioxidants are substances that may protect your cells against the effects of free radicals. Free radicals are produced by your body when it breaks down food, or by environmental exposures like smoke and radiation. Vitamin A also plays a role in your vision, bone growth, reproduction, cell functions, and immune system. It can come from plant and animal sources including colorful fruits and vegetables, liver and whole milk. Vitamin A is also added to foods like cereals.

Vegetarians and young children may need extra vitamin A. Also, those with diseases such as, alcoholism, liver disease, cystic fibrosis, and Crohn's disease may need more vitamin A.

Vitamin C is also an antioxidant. Vitamin C is important for your skin, bones, and connective tissue. It promotes healing and helps your body absorb iron. Vitamin C comes from fruits and vegetables. Good sources include citrus, red and green peppers, tomatoes, broccoli, and greens.

Pregnant/breastfeeding women, smokers, people recovering from surgery and burn victims may need extra vitamin C.

Vitamin D helps your body absorb calcium, which is needed for bone growth and health. A lack of vitamin D can lead to bone diseases such as osteoporosis or rickets. It also has a role in the health of your nerve, muscle, and immune systems. Your body forms Vitamin D naturally with you skin's exposure to sunlight. Also through your diet with vitamin D rich foods such as egg yolks, saltwater fish, and liver. Some other foods have vitamin D added, such as milk and cereal.

Seniors, breastfed infants, people with dark skin may need extra vitamin D, as well as those with certain conditions like liver disease, cystic fibrosis, and Crohn's disease.  Also, people who are obese or have had gastric bypass surgery.

Vitamin E is also an antioxidant. Vitamin E plays a role in the immune system and metabolic processes. Good sources of vitamin E are vegetable oils , margarine, nuts, seeds, and leafy greens. Most people get enough of this vitamin from their diet. Those with liver diseases, cystic fibrosis and Crohn's disease may need extra vitamin E.

Vitamin E supplements may be harmful to those who take blood thinners and other medications. Always check with your doctor before taking the supplements.

Vitamin K helps your body by making proteins for healthy bones and tissues.  It also makes proteins for blood clotting.  A person with a  lack of vitamin K may bleed too much.  Newborns need vitamin K.  Soon after they are born, they are given a vitamin K shot. 

Most people get their vitamin K from plants such as green vegetables, and dark berries.  Bacteria in your intestines also produce a small amount of vitamin K.

The B vitamins are:  B1 (thiamine), B2 ( riboflavin), B3 (niacin), B5 (pantothenic acid), B6, B7 (biotin),B12, and Folic acid.

Thiamine helps the body cells convert carbohydrates into energy.  It is essential for the functioning of the heart, muscles, and nervous system.

Good sources of thiamine are found in fortified breads, cereals, pastas, and whole grains, as well as, lean meats, fish, dried beans, peas, and soybeans.

A thiamine deficiency in the United States is most often seen in those who abuse alcohol.  A severe thiamine deficiency can cause brain damage.  There is no known poisoning linked to thiamine.

Riboflavin works with other B vitamins and is important for body growth and red blood cell production and helps in releasing energy form carbohydrates.

Good sources of riboflavin are lean meats, eggs, legumes, nuts, green leafy vegetables, dairy products, and milk.  Breads and milk are often fortified with it.  Because riboflavin is destroyed by light, foods containing it must not be stored in glass containers that are exposed to light.