The Secret of Yakult 1000

Top left: Osamu Watanabe, Development Department Top right: Hideki Maruyama, Public Relations Department

Osamu Watanabe (hereafter referred to as W) of the Development Department:"I appreciate you saying that. Before this product was released, our company had a product called 'Yakult 400', which was released in 1999 and had the highest number of bacteria. Since then, we have continued to develop it to have an even higher number of bacteria, and we finally managed to launch 'Yakult 1000' in October 2019. So, it took Yakult 1000 about 20 years of research and development to reach the market, and it is the culmination of that."

Y: "It took 20 years for Yakult 1000 to be released after Yakult 400?"

W: "There are two reasons why it took so long. The first is that it is very difficult to increase and maintain the number of bacteria in a product. The second is that we already have Yakult 400, and we had to provide a different value to customers from Yakult 400. We needed to be able to explain that value scientifically before we launched it. In order to promote the effects and functions of a food, rather than a drug, we need to provide proper evidence and obtain government permission or submit a notification as a specific health food or functional food. For Yakult 1000, we conducted clinical trials (click here for details on the clinical trial data) to demonstrate that it "has the function of relieving stress in situations where temporary mental stress is present and improving sleep quality (depth of sleep, refreshing awakening)," and after obtaining the data, we submitted a notification as a functional food. These are also reasons why it took so long."

Y: First of all, what is Shirota strain? Is it a lactic acid bacterium? I've heard the word lactic acid bacteria since I was a child, and I have the image that it improves stomach conditions, etc.

W: Yes, it is lactic acid bacteria. Yakult was created by a medical doctor named Minoru Shirota. He aspired to develop preventive medicine to prevent illness in the 1920s, when Japan's sanitary environment was still poor and many children died from infectious diseases. He believed that intestinal health could lead to longevity and disease prevention, and discovered that lactic acid bacteria suppress harmful bacteria in the intestines. There are genera and species of lactic acid bacteria, and even the same type of lactic acid bacteria has completely different characteristics depending on the strain. Bacteria that produce lactic acid fall into the category of lactic acid bacteria, but even if you ingest lactic acid bacteria, there is a barrier of digestive fluids such as gastric juice and bile, which have strong bactericidal properties, so many of them die before reaching the intestines. Lactobacillus casei Shirota strain is a bacteria that has been strengthened and cultured to reach the intestines alive, and it can be said to be a carefully selected bacteria.

Y: "There are many different types of lactic acid bacteria in the category of lactobacillus, but you discovered that this was the lactobacillus that could overcome stomach acid and reach the intestines! So you were saying in the 1920s that a healthy intestinal environment was important for good health?"

W: Yes, that's right. Our company has a philosophy that is the basis of our business, called "Shirotaism." It is the idea of "preventive medicine," "a healthy intestine leads to a long life," and "affordable prices for everyone." Shirota has been advocating these ideas since the 1930s, when the business began. In recent years, the importance of preventive medicine and the fact that intestinal bacteria are related to health in various ways have been scientifically proven.

Y: "In the 1920s, even if Shirota had said, 'You should improve your intestinal environment for your health!', ordinary people would have been like, 'What are you talking about?' (laughs)."

W: "That may have been the reaction (laughs). But the company Yakult was started when people who agreed with Shirota's vision formed a team to sell Yakult. I think the Yakult business was started because there were people who sympathized with Shirota's vision even back then."

Y: "That's amazing, isn't it? Mr. Shirota and those around him may have had the conviction that the intestinal environment is important, but spreading that knowledge to the world through the product Yakult is something you can't do without self-confidence. Most people at the time weren't even aware of the intestinal environment. It's amazing that they've managed to grow it into such a big company. Mr. Shirota is kind of like an alien (laughs)."

Public Relations Office, Hideki Maruyama (hereafter: M):"However, our business did not grow smoothly from the beginning. As I mentioned earlier, general consumers had a poor understanding of lactic acid bacteria, and many people had a negative image of bacteria when they heard about them. So we carefully explained to our customers that there are bacteria that are beneficial for the body."

Y: "I see. Nowadays, we think of lactic acid bacteria as being good for the body, but back then, if you heard the word "bacteria," you might have thought of germs."

M: "We started by asking, are bacteria really good for the body? We explain what lactic acid bacteria are, and we make it a priority to make sure that our customers are convinced when they drink our products. We also sell our products overseas, but because bacteria are often referred to as bacteria overseas, some people have a negative impression of our products. We have popularized our products by dispelling such impressions."