Rationale for Correct Answer

The correct answer is: Probiotics are associated with improved disease severity and mental health in patients with MS

Population studies have found different bacterial compositions in guts of people with and without MS, even in identical twin studies.1 Altered levels of microbial metabolites lead to immune dysregulation through multiple pathways, causing neuroinflammation and increased permeability of the intestinal barrier and BBB.1,2 Inflammatory immune markers then have access to the brain. The gut biome also regulates CNS activity through the hypothalamic-pituitary-adrenal (HPA) axis and neuroendocrine system.2 In small, placebo-controlled trials, probiotics are associated with a variety of benefits in patients with MS, including immune activity, insulin sensitivity, lipid metabolism, disease severity, and mental health.2

References:
1. Ghezzi L et al. J Clin Invest. 2021. 131:e143774.
2. Dziedzic A et al. Int J Mol Sci. 2022;23:14478.