Probiotic Blend May Help Reduce Upper Respiratory Tract Infection Symptoms

Upper respiratory tract infections (URTIs) are contagious infections caused by a variety of bacteria and viruses. Symptoms include cough, sneezing, nasal congestion, fever, and sore throat. A new study suggests that supplementation with five probiotic strains may help reduce symptoms of URTIs by up to 27%.

For their study, the researchers used data from the PROMAGEN trial, which included 220 overweight or obese adults. Half were given a probiotic supplement containing the probiotic strains Lactobacillus acidophilus CUL60, Lactobacillus acidophilus CUL21,  Lactobacillus plantarum CUL66, Bifidobacterium bifidum CUL20, and Bifidobacterium animalis subsp. Lactis daily for 6 months. The other half received a placebo. Participants maintained daily symptom diaries during the study, which included 5 symptoms of URTIs - cough, sore throat, headache, muscle ache, and wheeze.

Participants in the probiotic group saw a 27% reduction in URTI symptoms compared to the placebo group. The greatest benefits were seen in participants who were 45 or older and in those with a BMI of at least 30 kg/m2. The reduction in symptoms was seen after 2 weeks of probiotic supplementation.

The study was conducted by researchers from Imperial College London. It was published online ahead of print on March 25, 2021 in the journal Gut Microbes.