Multiple sclerosis is called an autoimmune disease because the immune system plays a fundamental role in its evolution. However, what causes MS is not fully understood.

Finding the cause would help the search for a cure. So researchers have being trying to find what leads the immune system to react against the myelin in the central nervous system.

No-one has found the solution yet, but all the findings so far suggest that MS does not have a single cause. Several factors might be involved, and at present the so-called multifactorial hypothesis is the most plausible explanation for MS.

The multifactorial hypothesis says that genes, viruses, nutritional factors, vitamin deficiencies and other factors can interact and, between them, lead to MS.

In 2013, researchers from Yale and Harvard Universities showed that increased dietary salt intake might contribute to the development of autoimmune diseases.

More recently, other researchers from Argentina and the USA looked at the role of salt intake in MS.

In August 2014, they published the results of their research, in which two groups of relapsing-remitting MS were studied. All underwent clinical assessments and MRI scans, while salt intake was measured from their urine samples.

Correlations between the number of lesions in patients’ brains and the level of salt intake were investigated.

The researchers found that patients with a higher salt intake had a more severe inflammation, with more relapses and active lesions on MRI scans.

The results support the theory that nutritional factors, including salt, can be involved in MS. This means that doctors should encourage their patients to follow a healthy diet.

Of course, following these findings, clinical trials on salt intake should be proposed by researchers to establish whether reduction of salt intake might lead effective benefits in patients with MS.