Both vitamins and minerals are essential in the diet in small quantities.The term ‘vitamin’ was not coined until early in the 20th century, to describe those chemicals in food without which a pattern of deficiency symptoms (often called a deficiency syndrome) occurs. Minerals, also called mineral elements, are those elements other than carbon, hydrogen, oxygen and nitrogen that are found in the body. This unit looks at the two main groups of vitamins: the fat-soluble vitamins A, D, E and K, and the water-soluble vitamins, those of the B group and vitamin C. It also examines the major mineral elements, and the importance of fluid balance in the body. This study unit is just one of many that can be found on LearningSpace, part of OpenLearn, a collection of open educational resources from The Open University. Published in ePub 2.0.1 format, some feature such as audio, video and linked PDF are not supported by all ePub readers.