Got a Cold? Try Probiotics!

Elisha Iveson Lifestyle Writer

We're currently having the hottest UK summer in what feels like ages and so it might seem a tad premature to discuss protecting yourself against the likes of the common cold and flu virus. But, results of a recent human trial1 published in the clinical journal Synthetic and Systems Biology already have us feeling much more clued up on those dreaded winter bugs!

Could probiotic strains reduce cold and flu-like symptoms and boost immunity?
Could probiotic strains reduce cold and flu-like symptoms and boost immunity?

Research from the adult study showed that three particular probiotic strains found in a probiotic drink are “safe and effective for fighting the common cold and influenza-like respiratory infections by boosting the immune system.” The probiotics used included two strains of Lactobacillus paracasei, and Lactobacillus fermentium PCC®.

Up to 70% of the immune system is based in the gut, hence why good bacteria supplements are thought to be a great option for restoring balance when cold or flu-like symptoms appear. Go gut health! The authors expand on this concept in relation to their study, saying:

“The human gut microbiota is an important environmental factor for human health with evolutionarily conserved roles in immunity, metabolism, development, and behaviour of the host. Probiotic organisms are claimed to offer several functional properties including stimulation of immune system. The purpose of this study is to investigate the effects of a probiotic supplementation on adults who have contracted the common cold four or more times in the past year.”

The single centre, randomised, double-blind, placebo-controlled study included 134 volunteers who 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. The team’s results from the 12-week study period of those participants recruited from Beijing Chaoyang Hospital were as follows:

  • 16.4% from the placebo group had an influenza-like illness with body temperature higher than 38 °C and at least one of the upper respiratory infections (URI) symptoms (e.g. cough, nasal congestion etc.) compared to 4.5% of those taking probiotics
  • 37.3% from the placebo group had no fever, but still showed at least one URI symptom compared to just 19.4% of those taking probiotics
Up to 70% of the immune system is based in the gut

Whilst the study authors suggested that there may need to be “additional in vivo studies to confirm that probiotic-mediated immune support prolongs resistance to various infections and diseases in humans”, they concluded from their trial and wider research that…

“Numerous studies have illustrated the effects of the intestinal microflora on the functioning immune response, therefore, it seems reasonable that changing the microflora with probiotics could potentially modulate the immune response and, in fact, improve the immune status of individuals.”

We can’t wait to find out more about the possibilities of friendly bacteria as we get closer to cold and flu season. Probiotics played a key role in this trial and many strains have been extensively researched for health benefits, including supporting immunity, side effects during antibiotic treatments, diarrhoea and lactose intolerance.

Looking for some similar blog posts to brush up on your bacteria facts? Check out this other related article from our Probiotics Learning Lab:

Probiotics for your family's immunity

Healthcare practitioners may also like to take a look at this article:

Probiotics for Immunity: a Look at the Research


  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.