The National Institute of Neurological Disorders and Stroke (NINDS) estimated that each week in the United States, 200 people are diagnosed with multiple sclerosis. An autoimmune disorder, multiple sclerosis affects the central nervous system—the brain and spinal cord. In the central nervous system, glial cells, oligodendrocytes, make up the myelin sheath that covers the axon of the neuron. In multiple sclerosis, the immune system attacks this myelin sheath, damaging it and leading the problems with neurological communication. The myelin sheath in the peripheral nervous system, which consists of the nerves outside of the brain and spinal cord, remain intact in multiple sclerosis patients, as this myelin is made from a different type of glial cell (Schwann cells).
The symptoms that a multiple sclerosis patient has depends on where in the brain the lesions occur. MedlinePlus noted that prognosis is better for multiple sclerosis patients who are female, have infrequent attacks, were younger than age 30 at the onset of the disorder, have relapsing-remitting multiple sclerosis, or have limited disease as indicated by a brain scan.
Complications are possible in multiple sclerosis. One issue that multiple sclerosis patients may develop is osteoporosis, which is a thinning of the bone tissue. Patients with osteoporosis may experience bone pain, neck pain, stooped posture, fractures or a loss of height. Doctors may recommend taking vitamin D and calcium supplements. Vitamin D supplements may provide a benefit with multiple sclerosis itself. Multiple sclerosis rates are higher in areas further away from the equator—five times more frequent in temperate climates, according to the NINDS—suggesting that vitamin D may play a protective role.