Too much salt appears to be bad

Farez MF, Fiol MP, Gaitán MI, Quintana FJ, Correale J.
Sodium intake is associated with increased disease activity in multiple sclerosis. J Neurol Neurosurg Psychiatry. 2014. pii: jnnp-2014-307928. doi: 10.1136/jnnp-2014-307928. [Epub ahead of print

BACKGROUND:Recently, salt has been shown to modulate the differentiation of human and mouse Th17 cells and mice that were fed a high-sodium diet were described to develop more aggressive courses of experimental autoimmune encephalomyelitis. However, the role of sodium intake in multiple sclerosis (MS) has not been addressed. We aimed to investigate the relationship between salt consumption and clinical and radiological disease activity in MS.
METHODS: We conducted an observational study in which sodium intake was estimated from sodium excretion in urine samples from a cohort of 70 relapsing-remitting patients with MS who were followed for 2 years. The effect of sodium intake in MS disease activity was estimated. We then replicated our findings in a separate group of 52 patients with MS.
RESULTS: We found a positive correlation between exacerbation rates and sodium intake in a multivariate model adjusted for age, gender, disease duration, smoking status, vitamin D levels, body mass index and treatment. We found an exacerbation rate that was 2.75-fold (95% CI 1.3 to 5.8) or 3.95-fold (95% CI 1.4 to 11.2) higher in patients with medium or high sodium intakes compared with the low-intake group. Additionally, individuals with high-sodium intake had a 3.4-fold greater chance of developing a new lesion on the MRI and on average had eight more T2 lesions on MRI. A similar relationship was found in the independent replication group.
CONCLUSIONS:Our results suggest that a higher sodium intake is associated with increased clinical and radiological disease activity in patients with MS.

It was suggested in animals that too much salt was not a good thing for EAE. Should we take this with a pince of salt or take notice. 

This study looked at salt intake and disease activity and found that MSers having lots of salt in their diet was associated with a 3 fold higher relapse rate  "western Diets" can have high salt, fat, sugar etc. Is this a reason to MS going up. High salt consumption has been associated with a number of health issue. Another study presented at ACTRIMS/ECTRIMS 2014 also pointed a finger at salt and enhanced immune response arguing that in blood the salt level is lower than tissues and by enhancing salt levels you make the immune cells behave like they are in tissues and have enhanced immune reactivity but we will diiscuss this when it is published.

Whilst we need to see replication salt intake is something that is in your control. ProfG may comment on this further

CoI : None