The Yakult Company

Our History & Research

Yakult is a fermented milk drink containing Lactobacillus casei Shirota (L. casei Shirota), the strain of bacteria unique to Yakult. In the field of probiotics and microbiology, Yakult has an unparalleled reputation for quality, safety and scientific research, with over 100 published human clinical trials.  It is widely acknowledged by scientific experts as a good quality probiotic supported by a substantial evidence base, and is recommended and used by healthcare professionals in many countries.

Science has always been at the heart of the Yakult company, since the microbiologist Dr Shirota selected and cultivated L. casei Shirota and produced the first bottle of Yakult in Japan in 1935. Continuing this passion for science, Yakult remains at the forefront of scientific research and education, and is committed to supporting healthcare professionals in enhancing the understanding of probiotics.

Dr Shirota

Dr Shirota, founder of Yakult and a microbiologist at the University of Kyoto’s School of Medicine in Japan, was devoted to ‘preventative medicine’ and harnessing the action of beneficial microorganisms.

In the 1920s, inspired by the work of Elie Metchnikov, Dr Shirota focused his research on lactic acid bacteria to improve or maintain human health. Recognising that Lactobacillus bacteria most suited his purpose, he carefully selected strains that would survive the intestinal tract, resulting in the selection and cultivation of L. casei Shirota.

1899 Dr Shirota
Research Centre

Research Centres

At Yakult’s research centres in Japan and Belgium, scientists are continuously investigating the role and application of intestinal bacteria in health and disease. 

Yakult Central Institute (Tokyo, Japan), established in 1955 and refurbished in 2015, has about 300 employees conducting cutting-edge research to seek new scientific advances in the application of intestinal bacteria.

Yakult Honsha European Research Centre (Ghent, Belgium) opened in 2005, and focuses on the application of intestinal bacteria in the European population, using technology developed by Yakult scientists. 


Yakult & Research

Yakult has substantial scientific data from over 80 years of research, including over 100 publications of human trials.  Several trials have shown that L. casei Shirota survives the human gastrointestinal tract, and positive outcomes have been shown in people in good health and with differing health conditions. 

Yakult continues to support independent research in hospitals, universities and institutes worldwide, including the UK and Ireland, to further investigate the effects of L. casei Shirota.

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Gut Health

The health of the gut is vital for it to perform its function of digesting and absorbing food.

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Meet the science team

Find out who's who in the Yakult Science Team.

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Read about the research behind the bacteria strain in Yakult.

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