FUNCTION OF WATER-SOLUBLE VITAMINS

Water-soluble vitamins are those that dissolve in water upon entering the body. Because water-soluble vitamins dissolve in water, they enter the bloodstream directly, where they are able to perform their functions. Your body cannot store these vitamins, however. To ensure that water-soluble vitamins perform their appropriate functions in your body, you must consume them every day.

Thiamin

Thiamin, also referred to as vitamin B-1, helps your body convert carbohydrates into energy. Thiamin also plays a role in maintaining the health of your nervous system, ensuring that nerve signals travel efficiently and promoting a healthy appetite.

Riboflavin

Riboflavin, or vitamin B-2, helps your body metabolize all of the macronutrients -- carbohydrates, protein and fat -- into energy. Riboflavin also plays an important role in keeping your skin healthy and maintaining vision.

Niacin

Niacin, also referred to as vitamin B-3, allows your body to metabolize protein and fats and promotes a normal, healthy appetite and proper digestion. Niacin also helps keep your skin and nervous system healthy. High doses of a specific form of niacin called nicotinic acid can also help lower triglyceride levels and reduce your risk of heart disease. Only take high doses of nicotinic acid under the supervision of your doctor.

Pantothenic Acid

Pantothenic acid, or vitamin B-5, aids in the digestion of carbohydrates, protein and fat and allows your body to process the nutrients from these foods. Pantothenic acid also plays a role in building healthy red blood cells and ensuring that your body is able to form hormones.

Vitamin B-6

Vitamin B-6, less commonly known as pyridoxine, plays an important role in the metabolism and absorption of protein and fats. Vitamin B-6 also helps create red blood cells and plays a role in maintaining blood sugar levels. Your body needs vitamin B-6 to break down the minerals copper and iron.

Vitamin B-12

Vitamin B-12 plays important roles in the creation of red blood cells and the genetic material -- DNA and RNA -- in the nucleus of all of your cells. Vitamin B-12 also helps protect your nerve cells to ensure that nerve signals can travel efficiently throughout your body.

Biotin

The most well-known role of biotin is the metabolism of carbohydrates, protein and fat, according to "Nutrition and You" by Joan Salge Blake. Biotin helps your body create red blood cells and keeps your nervous system healthy. Biotin also plays a role in fat synthesis.

Folate

Folate helps your body create new cells, including red blood cells. Because of this role of folate, the vitamin is particularly important in preventing birth defects of the brain and spine, known as neural tube defects. Folate also plays a role in protein metabolism and helps lower the levels of homocysteine, an amino acid, in your body. High levels of homocysteine can lead to heart disease.

Vitamin C

Vitamin C allows your body to produce collagen, the most abundant protein in your body. Collagen helps connect your tissues and keeps your bones, teeth and blood vessels healthy. Vitamin C also plays a role in the health of your immune system and helps your body properly absorb the minerals iron and calcium and folate. Vitamin C also acts as an antioxidant, protecting your cells from damage.