Does eating more meat and amino acid supplements lead to higher risk of MS?

Multiple sclerosis (MS) is a chronic autoimmune disease that affects the central nervous system. It is driven by an overactive immune response, where T cells (a type of immune cell) mistakenly attack myelin, the protective covering of nerve fibres, leading to inflammation and nerve damage. While genetic factors play a role in MS, environmental influences are increasingly recognised as important contributors to MS development and progression.

The effects of diet on MS risk and progression are complex and consistent evidence is lacking. However, recent research suggests that specific dietary changes may have potential to impact MS. Dr Tan’s previous studies found a link between high meat consumption and greater pro-inflammatory T cell activity in people with MS. Since meat is rich in branched-chain amino acids (BCAAs)—including leucine, isoleucine, and valine—Dr Tan and his team studied their role in immune regulation.

In laboratory models, the team discovered that a diet high in BCAAs increased T cell activity even at resting state. This was linked to stronger responses of the T cells when they reacted to specific molecules. Further laboratory experiments found that adding BCAAs amplifies the inflammatory T cell responses against myelin.

Given the important role of T cells in MS, Dr Tan predicts that increasing BCAA in the diet may worsen disease symptoms in a laboratory model of MS. To explore this, they will study (1) how varying the level of BCAAs in diets impact disease severity and (2) the specific effects of individual BCAAs—leucine, isoleucine, and valine—on disease progression.

These findings could provide valuable insights into dietary influences in MS and may pave the way for dietary strategies to help manage the disease.