Evidence suggests that the gut microbiome may play a role in susceptibility to various diseases, including those affecting the brain. Probiotics are friendly, live bacteria that benefit the digestive system and are being explored for their potential effects on a range of diseases, including obesity, colorectal cancer, cardiovascular disease, and ALS. In worm models of ALS, the probiotic formulation Lacticaseibacillus rhamnosus HA-114 was shown to help prevent neurodegeneration and appeared to aid lipid metabolism within cells. Proper lipid metabolism is crucial for maintaining normal cellular energy levels and function. Further work confirmed the effects in ALS model mice before moving to human clinical trials. This Phase 2 study will recruit 150 participants, who will be randomly assigned to receive either the dietary supplement PROBIO_HA114 or a placebo orally for 24 weeks. The study will evaluate the safety and effectiveness of PROBIO_HA114 by measuring changes in a variety of biological measures, such as lipidomic and metabolite profiles, as well as the ALS Functional Rating Scale-Revised (ALSFRS-R) score.