Vitamin A is essential for the growth of children, healthy skin and for normal vision. It is also important for a healthy immune system by strengthening resistance to infection. Vitamin A is found in liver, cod liver oil and dairy products. The body can also convert the antioxidant beta-carotene, found in yellow and orange fruits and vegetables and dark green vegetables into vitamin A. Vitamin A is a fat-soluble vitamin and is stored in the liver. Excess intake can be harmful so it is advised that pregnant women do not take vitamin A supplements or have liver or liver products that may contain large amounts of vitamin A.
Vitamin B1 (thiamin) is important for the release of energy from carbohydrate foods and for a healthy nervous system and heart. It is present in lots of foods but in small amounts. Important sources include whole grains, flour and bread, meat (especially pork), and fortified breakfast cereals.
Vitamin B2 (riboflavin) is necessary for the release of energy from food and normal growth. It is mainly found in milk and dairy products. Other useful sources include eggs, fortified breakfast cereals, liver and some green vegetables.
Vitamin B3 (niacin) is required for the release of energy from food, the normal structure of the skin and nervous system. The major source in the UK diet is from meat. It is also provided by liver, yeast extract, flour and bread.
Vitamin B5 (pantothenic acid) is necessary for release of energy from food. It is also important for the production of red blood cells. It is found in a wide variety of meat and vegetable sources including beef, chicken, eggs, potatoes, broccoli, tomatoes and whole grains.
Vitamin B6 (pyridoxine) is required for the metabolism of protein, a healthy nervous system and normal blood function. It is found in a variety of foods including beef, fish, poultry, eggs, whole grains and some vegetables
Vitamin B12 is important in the production of red blood cells and for helping to release energy from food. It is found in meat, fish, dairy products, yeast extract and fortified cereals.
Folic acid is required for the formation of red blood cells and the structure of the nervous system. It is essential in early pregnancy for the normal development of the growing embryo to prevent spinal defects such as spina bifida. Folic acid is found in green leafy vegetables, orange juice, yeast extract and breakfast cereals that have been fortified. Women of child-bearing age should ensure they get plenty of folic acid in their diet.
Vitamin C is an antioxidant and is important for a healthy immune system. It is required for the normal structure of connective tissue (in skin, cartilage and bone) and for the formation of the protein collagen required for the healing process. Vitamin C also plays an important role in the healing of wounds and fractures and assists in the absorption of iron in the body. It is found mainly in fruits and good sources include blackcurrants, strawberries, oranges and other citrus fruits.
Vitamin D is important for the absorption of calcium and phosphorus in the body helping form strong bones and teeth. Vitamin D is known as the sunshine vitamin as the body can produce it when exposed to sunlight. The action of sunlight on the skin is the most important source of vitamin D as very few foods contain the vitamin. Vitamin D, however, can also be found in oily fish, eggs and butter. Margarine is also fortified with vitamin D.
Vitamin E is an antioxidant and can help protect the cell membranes and the body from free radicals. Vitamin E is found in vegetable oils, nuts, seeds and avocado.
Vitamin K is found in both plant and animal sources and is essential for the normal clotting of blood and the development of bone structure. Deficiency is rare but newborn babies are usually given an injection of vitamin K. Sources include spinach and other leafy green vegetables.
Most of us should meet all our vitamin requirements by eating a healthy, well balanced diet. Certain groups, however, for example the sick, elderly, post-menopausal or pregnant women may need to take an additional vitamin supplement. Please consult your doctor for advice.