Probiotics are live microorganisms that support gut health. The gut contains 70% of the immune system, making a balanced gut microbiome important. Probiotics may be useful when medication, illness, stress, travel, or aging disrupt the balance of good and bad bacteria. Imbalances can cause issues like IBS, bloating, constipation or diarrhea. The document recommends probiotics containing multiple strains of bacteria or yeast, and highlights three probiotic supplements from Specialist Supplements containing different formulations to support gut health.