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Information for healthcare professionals

What is Yakult?


Yakult is a fermented milk drink containing Lactobacillus casei Shirota, a probiotic strain of bacteria unique to Yakult, which in 1930 was selected and cultivated by the scientist Dr Shirota in Japan.

Yakult is widely acknowledged by scientific experts as a good quality probiotic supported by a substantial evidence base. It is recommended and used by healthcare professionals in many countries. Scientific publications on Lactobacillus casei Shirota include human trials, case studies and mechanistic studies conducted by independent clinicians and researchers all over the world; several are from the UK.

The product, developed in 1935, has a substantial body of scientific data accumulated from over 75 years of research, including human trials in healthy people, people with sub-optimal health susceptible to illness and patients with differing health problems. Summaries and overviews of this research can be found here and include research into:

  • Fundamental studies - e.g. survival through the gut, improvement of the intestinal microbiota and gut milieu, mechanistic studies
  • Infectious diarrhoea - e.g. antibiotic-associated diarrhoea and Clostridium difficile infection; paediatric diarrhoea; norovirus
  • Other infections - e.g. Helicobacter pylori; human papillomavirus; HTLV-1 associated myelopathy; parasites; post-operative infections; upper respiratory tract infections
  • Gut function - e.g. constipation; irritable bowel syndrome (IBS); inflammatory bowel disease (IBD)
  • Immune modulation - e.g. investigations into effects on immune cells (e.g. natural killer cell activity), immunoglobulins (e.g. salivary IgA) and cytokines in different groups 
  • Sports-related research - e.g. immune function; ammonia buildup during exercise
  • Emerging areas of research - e.g. liver disease; obesity-related disease; cancer
Yakult Bottles

The company remains at the forefront of education and research into probiotics and is committed to supporting healthcare professionals in helping increase understanding of probiotic benefits: a popular study day is organised biennially in London, the company sponsors an award scheme for universities and institutes in the UK and Ireland; the Science Team gives educational seminars on request and produces a regular probiotic newsletter and other free educational resources.

For further enquiries, contact the Science Team in the UK or Ireland.

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