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October 2013

Probiotics May Reduce the Risk of Respiratory Tract Infections

The probiotic BI-04 may help reduce the risk of upper respiratory tract infections in healthy, active adults, according to a study.

Probiotics are beneficial bacteria (sometimes referred to as "friendly germs") that help to maintain the health of the intestinal tract and aid in digestion. They also help keep potentially harmful organisms in the gut (harmful bacteria and yeasts) under control. Most probiotics come from food sources, especially cultured milk products. Probiotics can be consumed as capsules, tablets, beverages, powders, yogurts, and other foods. Probiotic bacteria have been found to stimulate the body's immune system. They may also aid in several gastrointestinal illnesses such as inflammatory bowel diseases, antibiotic-related diarrhea, Clostridium difficile toxin-induced colitis, infectious diarrhea, hepatic encephalopathy, irritable bowel syndrome, and allergies.

Probiotics have been studied for the prevention of upper respiratory tract illnesses. The common cold, or acute viral nasopharyngitis, is a viral infection of the upper respiratory system, which may involve the nose, throat, sinuses, eustachian tubes (connects the ears to the throat), trachea (windpipe), larynx (voice box), and bronchial tubes (airways).

Colds are one of the leading causes of doctor visits and missed days from school and work. According to the Centers for Disease Control and Prevention (CDC), 22 million school days are lost annually in the United States as a result of the common cold. Over the course of a year, people in the United States suffer one billion colds, according to some estimates.

In the current study, researchers set out to determine whether supplementation with probiotics may impact illnesses of the respiratory system, stomach, or intestines in healthy, active men and women. They recruited 465 people with an average age of 35 and assigned them to one of three groups. The first group received the probiotic BI-04, the second group received the probiotic Bi-07, and the third group received a placebo mixed in a drink.

The results showed that the group that received BI-04 appeared to have a much lower risk of having an upper respiratory illness, compared to placebo. A significant difference in illness risk was lacking between the Bi-07 group and the placebo group. The BI-04 had the greatest delay in the time to an illness episode, compared to the other probiotic group and those who had received placebo.

The authors concluded that the probiotic Bl-04 appears to be a useful supplement in terms of helping to decrease the risk of upper respiratory tract infection in healthy, active adults.

Numerous other integrative therapies have been studied for the treatment of the common cold and other related illnesses. There is strong scientific evidence to support the use of andrographis, caffeine, and umckloabo for this purpose.

For more information about probiotics, please visit Natural Standard's Foods, Herbs & Supplements database.


  1. Natural Standard: The Authority on Integrative Medicine. 
  2. West NP, Horn PL, Pyne DB, et al. Probiotic supplementation for respiratory and gastrointestinal illness symptoms in healthy physically active individuals. Clinical Nutrition. 10 October 2013. DOI 10.1016/j.bbr.2011.03.031.

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