There is a vast amount of scientific research on probiotics in the public domain.
Probiotics are a group of beneficial microorganisms found in the gut. These, when taken in adequate quantities, are seen to confer a health benefit to the host. (World Health Organization). They help maintain a healthy balance in the gut microbiota and assist in building the body’s immune system. (The Good Gut – Justin and Erica Sonnenburg, 2015)
The protective role of probiotics in improving digestion is now fairly well established. Ritchie and Romanuk, 2012 did a meta-analysis of 74 studies, 84 trials, and 10351 patients. This analysis showed that probiotics are beneficial adjuncts in the treatment and prevention of gastrointestinal diseases.
The EFSA – European Food Safety Authority – has approved a group of probiotic bacteria genera and species in yogurt cultures. Canadian, Italian, and European regulators have accepted that probiotics help in maintaining a healthy gut. They recommend a level of billion colony forming units (CFU) per serving of probiotics in food.
The non-strain specific species of permitted probiotics are Bifidobacterium (adolescentis, animalis, bifidum, breve, and longum) and Lactobacillus (acidophilus, casei, fermentum, gasseri, johnsonii, paracasei, plantarum, rhamnosus, and salivarius) (Health Canada, 2009)
Clinical recommendation for those affected by digestive ailments is placed at 5 billion CFUs for children and 10 – 20 CFUs for adults. (Benjamin Kligler and Andreas Cohrssen Am Fam Physician. 2008 Nov 1:78(9):1073-1078). One to two billion CFUs per day are the recommended dose for healthy adults.
There are food and food supplements that contain probiotic bacteria. These include dietary supplements, pharmaceutical products, medical foods, infant formula, fermented foods like fresh yogurt, fermented milk, aged cheese, kimchi, craft beer, miso, fermented vegetables like sauerkraut pickles, sourdough bread, etc.
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