Autoimmune illnesses fall into two general categories: localised and systemic. Localised illnesses affect certain organs and include coeliac disease, type 1 diabetes, and thyroid illnesses such as Grave’s disease. Systemic autoimmune diseases affect multiple organs and tissues, and include rheumatoid arthritis, scleroderma and lupus.
Women have a higher susceptibility to autoimmune illnesses than men, and experts at Johns Hopkins University in the US estimate that roughly 75 per cent of people with autoimmune disease are women. Symptoms are most likely to come on in childbearing years, and although the reasons are largely unclear, new research suggests that it may be due to genetic factors linked to the X chromosome.
Evidence suggests a link between vitamin D deficiency and some autoimmune illnesses, including multiple sclerosis, Hashimoto’s disease and Crohn’s disease.