|Autoimmunity Versus Nutrition|
|Saturday, 06 August 2011 01:24|
Our immune system protects us from various diseases. However, at times it goes into an overdrive and attacks the body itself, leading to tissue destruction and degenerative diseases referred to as autoimmune diseases. Autoimmune disorders include multiple sclerosis, sarcoidosis, type 1 diabetes mellitus, lupus, rheumatoid arthritis, scleroderma, Graves’ disease, chronic thyroiditis, celiac disease, Crohn’s disease etc. Autoimmune problems have a strong genetic predisposition but triggers may include excessive sun, infections, drugs, or other conditions that stress the body including pregnancy.
Whether diet influences autoimmunity has been the subject of many unresolved debates. Interestingly, growing evidence indicates a role of diet in preventing, delaying or reversing the expression of genetically determined auto-immune diseases.
As the gut is a major site of many complex interactions, which control immunity, it is the largest interface between an individual and his environment and, therefore, provides the largest exposure for immune building micro-organisms and exposure to toxins and allergens. Strengthening the age-old adage, we are what we eat. This suggests an important role of pro-biotics and pre-biotics in autoimmunity. Scientists have explored the role of pre-biotic and pro-biotic supplementation in young infants to promote good bacteria and concluded that they were beneficial in the prevention of eczema. However, the effects in the treatment of eczema were less convincing.
Maternal diets during pregnancy and breast feeding too have been found to influence auto-immune processes. Breast feeding also emerges as a potentially protective factor for prevention of allergies and celiac disease.
Over the past years evidence has supported a major role for specific dietary factors including vitamin D, vitamin A, selenium, zinc, omega-3 fatty acids, pro-biotics, glutamine (an amino acid) and flavanols (plant chemicals which protect against disease) in influencing autoimmune diseases. Interestingly, effects of deficiency of vitamin D may extend beyond bone health and calcium balance. It has now been associated with increased autoimmunity and increased susceptibility to infections. Associations between vitamin D and auto-immune diseases have been confirmed in multiple sclerosis and rheumatoid arthritis.
Studies also indicate that vitamin A can be instrumental in the prevention of intestinal inflammation and auto-immunity. Supportive function of selenium in health and disease, including autoimmune diseases, is well documented.
Several animal and human studies have shown that diets high in omega-3 fatty acids, the kind of fat found in fish and flaxseeds, have a role in reducing the risk and treating autoimmune diseases. Omega-3 fatty acids not only prevent heart disease but may also reduce the risk of autoimmunity.
Dietary modification has shown its greatest beneficial effect when started prior to or immediately after the onset of disease. Also a golden rule, the old age principle of balance prevails. Optimum but balanced food intake maintains healthy growth and disease-free lifespan.
Ishi Khosla is a former senior nutritionist at Escorts. She heads the Centre of Dietary Counselling and also runs a health food store. She feels that for complete well-being, one should integrate physical, mental and spiritual health. According to her: “To be healthy should be the ultimate goal for all.”
Khosla, I (2011), "Autoimmunity versus nutrition", Indian Express; original article can be viewed here.