Vitamins are substances needed in small amounts in the diet for growth and maintenance of body tissues. It should be noted that vitamins do not provide energy but help in some energy yielding chemical reactions. Some vitamins are soluble in fat (vitamins K, A, D and E) whilst others are soluble in water (vitamins B and C). Majority of vitamins are indispensible to us and we need to consume them through our diets. Biotin, Vitamins D and K may be manufactured by our bodies. Vitamins can be obtained from both plant and animal sources.
Vitamin A deficiency is a serious health problem in 3rd world countries and is the leading cause of non-accidental blindness. This has even compelled the Ministry of Health to provide vitamin A supplements to children regularly. Over 90% of the body’s vitamin A is stored in the liver and the role played by this vitamin in facilitating vision is its main function. It also helps the body to fight infections. Vitamin A also helps promote growth and good skin. Some rich sources of vitamin A includes liver, eggs, fish oils, dark green vegetables such as kontomire and fruits such as mangoes and carrots. Dry skin is another problem associated with lack of this vitamin.
Our bodies are capable of producing vitamin D from sunlight. The amount of sunlight needed for this process depends on skin colour and age. Deficiency of vitamin D leads to rickets and osteomalacia. Vitamin D helps in regulating blood calcium levels. When this does not take place efficiently, bones do not harden well, become weak and bow leading to rickets in children. When it occurs in adults it is osteomalacia and it can lead to fractures in the hip, spine and other bones. It also helps to maintain optimum calcification of bones. Vitamin D is also found in sardines, salmon and fortified milk.
What we call vitamin E is actually a family of eight naturally occurring compounds. Vitamin E is a powerful antioxidant. It helps protect cell membranes from oxidative destruction. The best sources of vitamin E are corn oil, soybean oil and groundnuts. Lack of this may lead to destruction of red blood cells. It can also lead to destruction of nerves.
The K vitamin is essential for blood clotting. This means lack of this vitamin can lead to excessive bleeding. Babies are born lacking this vitamin and need to be given an injection right after birth. The best sources of vitamin K are liver, green leafy vegetables such as kontomire, cabbage and green beans.
