Most of us have been told to take our vitamins, but few people
know why, and despite all the talk about them in modern culture,
vitamins remain something of a mystery. Vitamins are organic
substances, essential for maintaining life functions and
preventing disease among humans and animals and even some
plants. They are found in very small quantities in food; certain
health specialists recommend taking vitamin supplements to
augment the supplies in food, while others insist that a well-
balanced diet provides all the vitamins that an ordinary person
needs. Some vitamins, such as vitamin C and the B complex, are
water-soluble, which means that they are excreted easily and
must be ingested every day. Others, such as vitamins A, D, E,
and K, are fat-soluble and therefore are retained in the body's
fatty tissues. With such vitamins, there may be a danger of
taking too much, but in the case of most vitamins, the greatest
harm comes from not receiving enough. Vitamin deficiencies can
be the cause of rickets, pellagra