Infection is a colonization of the body by pathogenic microorganisms such as bacteria, fungi and viruses, that has a detrimental and debilitating impact on an individual. The pathogen can enter the body from outside via openings in the skin and other parts of the body. Or, it may be part of the normal microbial flora of the body and become infectious when the immunity of the individual is reduced due to other conditions. Diet and exercise play important roles in proper functioning of the immune system, and certain vitamins may help.
Vitamin A
Vitamin A is a fat-soluble vitamin that plays an important role in the formation and maintenance of healthy mucous membranes and skin and thereby prevents pathogens from entering the body. An article published in the September 2007 edition of the "Annals of Nutrition and Metabolism" states that vitamin A also plays an important role in both cell-mediated and antibody-mediated immune responses and a deficiency of this vitamin impairs the ability of the body to fight extracellular pathogens.
Vitamin A can be obtained from foods such as eggs, meat, milk, cheese, carrots, apricots and green leafy vegetables. Vitamin A supplements are also available in most pharmacies. The supplements are generally safe, although chronic overdose can lead to hypervitaminosis A that is characterized by blurred vision, bone pain, dizziness and headaches.
Vitamin B
Vitamin B is a group of eight vitamins including vitamins B-1, B-2, B-3, B-5, B-6, B-7, B-9, B-12 and folic acid that can be obtained from foods such as fish, meat, eggs, dairy products, beans and green leafy vegetables. Apart from being crucial for the proper functioning of organ systems in the body, vitamins B-1 and B-3 also have antiviral properties, according to the International Society of Orthomolecular Medicine. While vitamin B-1 has the ability to inhibit the replication of the HIV virus, vitamin B-3 may prevent viral infections by promoting tissue regeneration and wound healing. B complex supplements are also available in pharmacies and are safe to use as long as the dosage instructions are followed.
Vitamin C
Vitamin C is a water soluble vitamin with antioxidant properties. According to the Linus Pauling Institute, vitamin C helps to prevent infections by increasing the level of antibodies in the blood and by stimulating the production of white blood cells that attack bacteria and viruses. Foods such as citrus fruits, strawberries, tomatoes and green leafy vegetables are rich in vitamin C. Vitamin C supplements are also available. However, caution should be exercised, as an overdose can lead to upset stomach and diarrhea.
Vitamin D
Vitamin D is a fat-soluble vitamin that can be obtained from foods such as dairy products and meat, and from synthetic supplements. It can also be produced endogenously by the human body when exposed to sunlight. Apart from maintaining healthy bones and muscles, the "Annals of Nutrition and Metabolism" states that vitamin D deficiency can cause higher susceptibility to infections such as the common cold and flu due to impaired innate immunity and defects in antigen-specific cellular immune response.
Vitamin E
Vitamin E is a fat soluble vitamin that plays an important role in the functioning of the immune system and a June 2005 article published in the "Immunological Reviews" says that vitamin E deficiency in the elderly can lead to reduced production of antibodies and white blood cells, thereby increasing the risk of infections. Vitamin E can be obtained from foods such as olives, wheat germ, corn, nuts and seeds, and also from synthetic supplements. MedlinePlus, however, warns against the consumption of more than 400 IU of vitamin E per day, as it increases the risk of death.
References
- "Annals of Nutrition and Metabolism"; Contribution of Selected Vitamins and Trace Elements to Immune Function; Eva S. Wintergerst et al; September 2007
- Orthomolecular.org: Vitamins Reduce the Duration and Severity of Influenza
- Linus Pauling Institute: Vitamin C
- "Immunological Reviews"; Vitamin E and immune response in the aged: molecular mechanisms and clinical implications.; Meydani SN et al; June 2005
- MedlinePlus: Vitamin E
Member Comments