Multiple sclerosis (MS) is a chronic disease of the central nervous system that affects the brain and spinal cord. The exact cause of MS is unknown, but it is considered an autoimmune disease in which the bodys immune system attacks its own tissues. In the case of MS, the immune system attacks the myelin sheath in the brain and spinal cord, which is the layer that surrounds and protects nerve fibers. This immune system malfunction destroys the fatty substance that coats and protects nerve fibers, and when the protective myelin is damaged, the nerve fibers are exposed, and the messages that travel along that nerve fiber may be slowed or blocked. It isnt clear why MS develops in some people and not others, but a combination of genetics and environmental factors appears to be responsible. Some of the factors that have been suggested as possible causes of MS include:
- Autoimmune disorders
- Infectious agents, such as viruses
- Environmental factors
- Genetic factors
- Age
- Low levels of vitamin D and low exposure to sunlight
- A gene on chromosome 6p21
- Obesity
. It is important to note that while these factors may increase the risk of developing MS, they do not necessarily cause the disease on their own.
