Digestive problems? Try probiotics

The Bottom Line

  • Probiotics are “good” bacteria that promote gut health and keep harmful bacteria in check.
  • When given to people taking antibiotics, probiotics help prevent diarrhea associated with C. difficile.
  • There is evidence that probiotics improve symptoms of other gastrointestinal problems such as irritable bowel syndrome and chronic constipation.

Probiotics: They’re being added to more food items and touted as solving a wide range of health problems, boosting body functions from your brain to your breathing to your bowels. But is this just another fad? What are probiotics anyway? And do they live up to all the hype?

Probiotics are actually bacteria – the “good” kind. Our bodies have trillions of these microorganisms, some harmful but the majority of them beneficial. “Good” bacteria help break down food and keep the “bad” bacteria at bay. Probiotic bacteria are found in cultured dairy foods like yogurt, fermented vegetables like kimchi and sauerkraut, and foods fortified with probiotic bacterial cultures. They’re also available in capsules.

So they’re easy to find and consume… but are they really the “miracle cure” many claim them to be?

What the research tells us

Medications (especially antibiotics), stress, diet and other factors can alter the ratio of good to bad bacteria in your gut, causing infection and disease. This happens more often than you might think: antibiotics are one of the most prescribed medications in Canada and the US (and often prescribed unnecessarily… but that’s another story) (1;2). They’re important and effective in killing infection-causing bacteria, but they often end up killing a lot of good bacteria, upsetting that important balance and giving dangerous Clostridium difficile bacteria a chance to cause severe diarrhea and other bowel diseases, sometimes with fatal results (3).

That’s where probiotics – like Lactobacillus rhamnosus, Lactobacillus casei and Bifidobacterium lactis – come in. Research evidence shows that probiotics given to children and adults taking antibiotics successfully lowers the risk of C. difficile-associated diarrhea (4-6). There is also promising evidence that probiotics may help in the treatment of other common gastrointestinal problems, including irritable bowel syndrome and chronic constipation (7), conditions that affect more than 10% of the adult population (8;9).

As we continue to learn more about the role probiotics play in promoting health, go ahead and enjoy your yogurt, especially if you are prescribed antibiotics. Consuming more probiotic-rich food isn't likely to cause harm, and very well may help keep your gut balanced and happy!

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    1. Government of Canada. Canadian antimicrobial resistance surveillance system report 2016. [Internet] 2016. [cited March 2017]. Available from:https://www.canada.ca/en/public-health/services/publications/drugs-health-products/canadian-antimicrobial-resistance-surveillance-system-report-2016.html#a3-2-2
    2. Centers for Disease Control and Prevention. Be antibiotics aware: Smart use, best care. [Internet] 2021. [cited February 2023]. Available from https://www.cdc.gov/patientsafety/features/be-antibiotics-aware.html
    3. Oake N, Taljaard M, van Walraven, C et al. The effect of hospital-acquired Clostridium difficile infection on in-hospital mortality. Arch Intern Med. 2010; 170(2):1804-1810. doi: 10.1001/archinternmed.2010.405.
    4. Johnston BC, Ma S, Goldenberg JZ, et al. Probiotics for the prevention of Clostridium difficile-associated diarrhea: A systematic review and meta-analysis. Ann Intern Med. 2012; 157(2):878-888. doi: 10.7326/0003-4819-157-12-201212180-00563.
    5. Hempel S, Newberry SJ, Maher AR, et al. Probiotics for the prevention and treatment of antibiotic-associated diarrhea: A systematic review and meta-analysis. JAMA. 2012; 307(18):1959-1969. doi: 10.1001/jama.2012.3507.
    6. Goldenberg JZ, Yap C, Lytvyn L, et al. Probiotics for the prevention of Clostridium difficile-associated diarrhea in adults and children. Cochrane Database Syst Rev. 2017; 12:CD006095. doi: 10.1002/14651858.CD006095.pub4. 
    7. Ford AC, Quigley EM, Lacy BE, et al. Efficacy of prebiotics, probiotics, and synbiotics in irritable bowel syndrome and chronic idiopathic constipation: Systematic review and meta-analysis. Am J Gastroenterol. 2014; 109(10):1547-1561. doi: 10.1038/ajg.2014.202.
    8. Lovell RM, Ford AC. Global prevalence of, and risk factors for, irritable bowel syndrome: A meta-analysis. Clin Gastroenterol Hepatol. 2012; 10(7):712-721. doi: 10.1016/j.cgh.2012.02.029.
    9. Suares NC, Ford AC. Prevalence of, and risk factors for, chronic idiopathic constipation in the community: Systematic review and meta-analysis. Am J Gastroenterol. 2011; 106(9):1582-1591. doi: 10.1038/ajg.2011.164.

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