Micronutrients are vitamins and certain minerals that function in the metabolic and other processes in the body, in very small amounts. Some of them function in the production and differentiation of the immune system cells. When these vitamins and minerals are deficient, there will be a suppression of the immune system.

Among the phagocytes, for example, there is a lot of oxidative stress (destruction by free radicals) taking place. The free radicals released play positive roles as they join in the destruction of pathogens. A situation like this is commonly seen where there is vitamin E deficiency. Vitamin E functions in the balanced production and differentiation of the T-helper and T-suppressor cells.

T-suppressor cells are responsible for controlling the inflammatory response to prevent damage to the surrounding cells not involved in the inflammation. Deficiency of vitamin E suppresses the immune system by causing damage to the surrounding cells, a phenomenon that may lead to what is known as autoimmune response, whereby the immune system is said to attack and destroy the host cells and organs. Vitamin E deficiency may be due to failure to absorb it in the intestines due to the mal-absorption syndrome or in the elderly in whom absorption reduces with age.

Common sources of vitamin E are vegetables such as spinach, pumpkin, broccoli, red pepper, carrots and fruits – mangoes and pawpaw. Other sources are sunflower seeds and nuts. Apart from these, that should form part of our diet, taking vitamin E supplements can boost the immune system. Vitamin C has been found to improve the first line defense of the immune system by enhancing the function of the phagocytes. There is a lot of ongoing research work on the ability of vitamin C to boost the immune system with evidence that vitamin C enhances various aspects of the immune system. An important role of vitamin C is that it helps to regenerate vitamin E, thereby extending the immune system enhancing effect of vitamin E. Vegetable sources of vitamin C include Brussels sprouts, tomatoes, kiwi, broccoli, kale, red and yellow peppers, Moringa oleifera and sweet potatoes.

Fruits that have a high concentration of vitamin C are mangoes, oranges, grapefruit and other citrus fruits, pawpaw (papaya), strawberries and berries in general. Guardian