Vitamins contribute to all body processes and each vitamin has its own function. They are essential for optimal health. Vitamins fulfill an important role in the body’s metabolism by contributing to the metabolism of carbohydrates, fat and protein. 
There are water-soluble vitamins (such as vitamins B and C) and fat-soluble vitamins (vitamins A, D, E, K). The body cannot store large amounts of water-soluble vitamins; they have to be consumed on a daily basis. Fat-soluble vitamins, on the other hand, can be stored in the liver and fatty tissue. Although rare, the risk of toxicity is greater for fat-soluble vitamins than it is for the water-soluble vitamins.


There is no evidence that vitamins enhance performance. On the other hand, a shortage of vitamins can lead to a decrease in performance. Thus, a good vitamin status is necessary for an optimal performance. Eating a well balanced diet can prevent deficiencies.


Vitamin B complex
: B vitamins are involved in energy and carbohydrate metabolism. Some B vitamins, such as thiamin (B1), riboflavin (B2), niacin (B3), pantothenic acid (B5) and biotin (B7), enable the body to release energy from nutrients like carbohydrates and proteins. 
Pyridoxine (vitamin B6) helps metabolize amino acids (building blocks of protein). 
Cobalamin (vitamin B12) plays a role in the multiplying process of red blood cells (which carry oxygen).


Vitamin C (ascorbic acid)

: Vitamin C fulfills an important role in carbohydrate and protein metabolism and stimulates iron absorption. Vitamin C is also an antioxidant. Antioxidants protect against free radicals (unstable and highly reactive molecules in the body). Exercise induces the production of free radicals, which can affect performance in a negative way. Therefore, a proper intake of vitamin C is preferred.


Vitamin E (tocopherol)

: Vitamin E has antioxidant properties, just like vitamin C. Vitamin E has an important effect in the lungs, where the exposure of cells to oxygen is high.


Vitamin supplements are typically not needed when eating a well-balanced diet.