In the prospective study, a yogurt drink containing three probiotic strains, Lactobacillus paracasei, Lactobacillus casei 431, and Lactobacillus fermentium PCC, was shown to be effective in fighting cold and flu-like respiratory infections by boosting the immune system in subjects who contracted the common cold four or more times in the past year.
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Results of a human prospective trial1 published in the clinical journal Synthetic and Systems Biology suggest that a yogurt probiotic drink may help reduce the incidence of upper respiratory infections (URIs) and symptoms of the common cold. In the study, three probiotic strains, Lactobacillus paracasei, Lactobacillus casei 431, and Lactobacillus fermentium PCC, were shown to be effective in fighting cold and flu-like respiratory infections by boosting the immune system in subjects who contracted the common cold four or more times in the past year. All of the probiotics used in this study were supplied by Chr. Hansen (HÃ¸rsholm, Denmark) in lyophilized powder form.
The single center, randomized, double-blind, placebo-controlled study included 134 volunteers between the age of 25-45 who were recruited from the Beijing Chaoyang Hospital (Beijing). Subjects received daily doses of either 150 ml of a probiotic yogurt drink containing the three probiotic strains, or 150 ml of a placebo yogurt drink. Subjects were instructed to consume the drink after lunch daily for a total study period of 12 weeks. The researchers collected blood and fecal samples from subjects at baseline and at the end of the study.
Researchers observed a statistically significant difference between the probiotic and placebo groups in the incidence of URIs. Specifically, 16.4% of the placebo group demonstrated flu-like symptoms and at least one URI symptom, while only 4.5% of the probiotic group showed flu-like symptoms with at least one URI symptom, including cough, nasal congestion, headache, muscle pain, and others. In addition, 37.3% of the placebo group had no fever but did have at least one URI symptom, while 19.4% of the probiotic group had no fever but at least one URI symptom.
The study’s authors thus concluded this probiotic beverage is “safe and effective for fighting the common cold and influenza-like respiratory infections by boosting the immune system.” They added that while there is good evidence that probiotics provide support for the immune system, additional in vivo studies may be needed to confirm that probiotic-mediated immune support prolongs resistance to various infections and diseases in humans.
1. Zhang H et al., “Prospective study of probiotic supplementation results in immune stimulation and improvement of upper respiratory infection rate,” Synthetic and Systems Biology. Published online March 12, 2018.