Probiotic yogurt may ease common cold symptoms in healthy adults: RCT
Twelve weeks of consuming a yogurt formulated with Lactobacillus paragasseri SBT2055 (LG2055) led to fewer cold symptoms, such as runny nose, plugged nose, sneezing, sore throat, hoarseness, cough, headache, feeling tired, and fever, compared to the placebo group.
The study, which included 200 people, also found that the probiotic yogurt group had significantly greater changes in salivary sIgA levels. Secretory immunoglobulin A (sIgA) is found on bodily surfaces and in secretory fluids like mucus and is known to be the first line of defense in protecting against infection.
“The findings suggest that the incidence rates of the symptoms associated with common cold were lesser in the LG2055 group, and LG2055 might suppress the deterioration of physical conditions by maintaining and improving the host’s immune system,” wrote the researchers in Frontiers in Nutrition.
The 12 week randomized, double-blind, placebo-controlled, parallel-group comparative study included 200 healthy Japanese adults aged between 20 and 64 provided with a one bottle of drinkable yogurt per day with or without the LG2055 probiotic containing a minimum of one billion CFUs per 100 grams.
Analysis of data from 193 people showed that the cumulative days of cold symptoms were significantly lower for people receiving the probiotic yogurt. This result indicated that “the incidence rates of common cold symptoms were lower in the LG2055 group”, said the researchers.
In addition, there were greater changes in salivary secretory IgA levels in the probiotic group, although statistically these were not significant between the groups.
“These data suggest that LG2055 upregulates salivary sIgA production and contributes to protection from viral infection,” stated the researchers. “Although the difference in the sIgA levels between the two groups became non-significant at 12 weeks after starting intake, it could have been influenced by the large change in the sIgA level in the placebo group.
“In the early phase of a cold, inflammation occurs in the upper respiratory tract, including the throat and nose,” they explained. “Subsequently, viral multiplication induces an immune response from the host, and systemic symptoms (e.g., fever and feeling tired) then appear. The present findings in this study suggested that ingestion of DY containing LG2055 might suppress the early local symptoms of common cold and its subsequent systemic symptoms.”
Source: Frontiers in Nutrition
Published online, doi: 10.3389/fnut.2022.1063584
“Intake of Lactobacillus paragasseri SBT2055 improves subjective symptoms of common cold during winter season in healthy adults: A randomized, double-blind, placebo-controlled parallel-group comparative study”
Authors: E. Kobatake et al.