Probiotics show potential against common cold: Study

Daily supplements with probiotic Lactobacillus strains may reduce the incidence of acquiring the common cold by 12 percent, according to new research from probiotic player Probi.

Results of a randomised, parallel, double-blind placebo-controlled study with 272 subjects showed that daily consumption of Lactobacillus plantarum HEAL 9 (DSM 15312) and Lactobacillus paracasei 8700:2 (DSM 13434) reduced the incidence of one or more episodes of the common cold from 67 percent in the placebo group to 55 percent, according to findings published in the European Journal of Nutrition.

Furthermore, the number of days of symptoms for the cold was significantly reduced in people taking the probiotic supplements, from an average of 8.6 to 6.2, compared with placebo.

“Intake of the probiotic strains Lactobacillus plantarum HEAL 9 (DSM 15312) and Lactobacillus paracasei 8700:2 (DSM 13434) reduces the risk of acquiring common cold infections,” state the researchers, led by Anna Berggren from Sweden’s Probi AB.

The wider implications of gut health

The common cold is a viral infection primarily caused by rhinoviruses. It is the most common infectious disease in humans, and responsible for about 500 million illnesses in the US every year. According to a study published in the Archives of Internal Medicine, the common cold and related diseases costs the US about $40 billion every year (2003, Vol. 163, pp. 487-494.).

Probiotics, alone or in combination with prebiotics, have been reported to potentially reduce the incidence of upper respiratory track infections. Indeed, earlier this year Croatian researchers reported that Lactobacillus GG may decrease the risk of upper respiratory tract infections including rhinitis, pharyngitis, sinusitis, otitis, and the common cold in children attending day care centres (Clinical Nutrition, June 2010, Vol. 29, pp. 312-316).

According to the FAO/WHO, probiotics are defined as "live microorganisms which when administered in adequate amounts confer a health benefit on the host”.

Study details

Berggren and her co-workers tested the effects of L. plantarum HEAL 9 (DSM 15312) and L. paracasei 8700:2 (DSM 13434) on the incidence of the common cold in 272 healthy subjects. Participants were randomly assigned to receive either the daily probiotic supplements (one billion colony forming units) or a control for 12 weeks.

Results showed that, in addition to a reduction in the incidence of getting the common cold and the number of days with symptoms, a reduction in the severity of symptoms was also recorded. According to the EJN report, “the total symptom score was reduced during the study period from a mean of 44.4 for the control group to 33.6 for the probiotic group”.

Source: European Journal of Nutrition

Published online ahead of print, doi: 10.1007/s00394-010-0127-6

“Randomised, double-blind and placebo-controlled study using new probiotic lactobacilli for strengthening the body immune defence against viral infections”

Authors: A. Berggren, I. Lazou Ahren, N. Larsson, G. Onning