There are thirteen vitamins in humans: four fat soluble (A, D, E, and K) and nine water soluble (vitamin B complex and vitamin C). Water-soluble vitamins dissolve rapidly in water and are usually easily excreted by the body. Because they are not processed too soon, a steady intake is important. B vitamin supplements available for each vitamin: B1: thiamine, B2: riboflavin, B3: niacin, etc. Niacin, pantothenic acid, biotin and folate are recognized by name rather than by quantity. B vitamins are usually used in energy drinks and many are advertised with high levels of B vitamins boasting that they can 'go through the day and do not feel nervous or anxious. B vitamins are primarily absorbed in foods such as pork, fish and liver. Healthy vitamin B sources include vegetables (pulses or beans), whole grains, rice, bananas, chilli pepper, tempeh, brewer's yeast and molasses. While beverage yeast has been used to produce beer, its bioavailability varies from low to adverse, as drinking ethanol hinders the absorption of thiamine (B1), riboflavin (B2), niacin (B3), biotin (B7) and folic acid (B9). Vitamin C is needed for tissue growth and repair in all areas of the body. It is used as an essential protein for the development, repair and maintenance of cartilage, bones and teeth and assists in the absorption of iron.