Multiple sclerosis, MS is often seen as an immune reaction. However researchers surveyed 1,349 MS sufferers. The respondents were asked to reveal any allergic reaction to food, environmental factors or drugs, only those with a food allergy suffered more frequent relapses and had more severe pathological changes related to MS.
It is not yet know whether an allergy can cause the MS in the first place, but researchers do know that sufferers often experience a relapse after a reaction to food. This suggest that MS isn't just an immune reaction but is more closely assocated with gut and inflammatory responses to foods. This discovery by researchers at Brigham and Women's Hospital in Boston ties in with earlier observations that people with MS seem to suffer relapses after an allergic reaction - but nobody has been sure it was a reaction only to food.
Researchers concluded there is a strong link between MS and food allergy. The common factor seems to be inflammation in the gut.
Fakih R, Diaz-Cruz C, Chua AS, Gonzalez C, Healy BC, Sattarnezhad N, Glanz BI, Weiner HL, Chitnis T. Food allergies are associated with increased disease activity in multiple sclerosis. J Neurol Neurosurg Psychiatry. 2019 Jun;90(6):629-635.