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Probiotics can improve immune function and reduce the chances of getting a viral respiratory infection, such as the flu, according to a review of studies that followed more than 700 people. Three popular strains of probiotics found in supplements proved to be effective: Lactobacillus was best, followed by Bifidobacterium, and then Lactococcus.
A healthy balance of probiotics in the gut enhances digestion, improves nutrient absorption, and enables good immune function to resist viral infections. Although diet plays a pivotal role, probiotic supplements are an additional, helpful tool.