Most MS patients use unconventional therapies, usually as complementary measures in addition to the conventional treatment. Only a few adequate clinical trials exist in this field. By definition, the efficacy of these therapies is unproven. Moreover, the possible risks are also largely unknown. Some therapies rely on rational pathophysiological considerations, other must be regarded as potentially harmful. The influence of diet on MS is unproven. Possibly, unsaturated fatty acids are beneficial. However, a few randomized trials yielded inconclusive results. Long-term supplementation of Vitamin D is associated with a decreased MS incidence. There is, however, insufficient evidence for an influence of Vitamin D on the course of the disease. Because of the high prevalence of osteoporosis in MS patients, prophylaxis with Vitamin D and Calcium is widely accepted. The effects of various minerals, selenium, antioxidant compounds, fish oil or vitamins remain speculative. Many patients use cannabis to alleviate spasticity and pain. Small series indicated positive effects, but randomized trials were negative for spasticity. However, many patients report subjective improvement under cannabis even if their objective parameters remain unchanged. Hyperbaric oxygenation was the subject of several small studies with heterogeneous results which, overall, do not support its use. Generally, physical therapies are perceived as an established therapy for MS. Short-term effects are probable, whereas the possible favourable long-term effects are unclear.

Schwarz, Leweling, Meinck (2005). [Alternative and complementary therapies in multiple sclerosis]. Fortschritte der Neurologie-Psychiatrie, 2005 Aug;73(8):451-62. https://www.ncbi.nlm.nih.gov/pubmed/16052439