Oxygen is the base for all functions of the body. During various functions, oxygen can interact with body compounds to produce highly unstable molecules known as free radicals. Free radicals are also generated by the cells of body’s immune system to inactivate various microbes  invading the body. Environmental factors such as radiation, cigarette smoke, or pollution can also generate them.

These free radicals need to couple with another electron to become stable, otherwise they remain highly reactive, causing cell and tissue damage. This leads to chronic diseases like cancer, arthritis coronary artery disease, among others. They are responsible for reducing immunity of the body, making it prone to infections and malignancies. They also cause degenerative changes in the body related to aging.

Antioxidants are chemical substances that neutralise these free radicals and thus prevent the resultant damage. Much research has focused on use of naturally occurring antioxidants to prevent or retard chronic degenerative diseases and aging.

There are a wide variety of antioxidants and are present in abundance in whole grains, vegetables and fruits. Vitamin A (retinol) is synthesised in the body by beta carotene.

It is present in dark green, yellow and orange vegetables and fruits. Carrots, squash, broccoli, tomatoes, mango, orange, apricot are some of the naturally occurring substances rich in beta carotene and vitamin A.

Vitamin C, a water soluble vitamin is also abundantly present in nature and has strong antioxidant properties. Therefore, it helps to improve immunity of body Citrus fruits like orange and sweet lemon are rich source of vitamin C.

It is also present guavas, green pepper, tomatoes, broccoli, strawberries, black currant, blue berries, raw cabbage, among others.

Vitamin E is useful to prevent aging and  is also protective  against coronary artery disease. Whole grains are rich source of vitamin E Wheat bran is  a  natural source of vitamin E. Therefore, it is recommended to use whole wheat flour instead of the refined white flour that contains only carbohydrates.

Vegetable oils and fish liver oil are also rich in vitamin E.

Vitamin C and E work together to prevent oxidation of lipids in the blood stream.  Thus, they retard atherosclerosis and prevent coronary artery disease.

Groundnuts have antioxidant properties, which is enhanced by roasting. Barley, oat, millets and corn are  cereals rich in anti oxidants, using which one can boost the body’s immunity. Certain spices like clove and cinnamon are rich in antioxidants and are very beneficial in multiple ways  for the human body.

It is recommended that one takes a diet rich in fresh fruits, green vegetables, other vegetables, whole grains and fish. It is best to take antioxidant substances in natural form rather than taking artificial supplements as in form of tablets. 

Natural substances contain a combination of many macro and micro nutrients which provide antioxidants and are useful for the body in multiple ways.

It is also advisable to take these substances in the form of small frequent meals to ensure optimal utilisation and benefit to the body. Taking them in a large amount at one time can in fact be harmful, the excess can damage cells.

To keep body healthy, prevent chronic diseases and aging, one should regularly take a diet rich in antioxidants, that is to say, fresh fruits, vegetables, nuts and whole grains.

Dr Rachna Pande is a specialist in internal medicine at Ruhengeri Hospital