Yakult

Key takeaways

Yakult belongs to science; place it in that map before memorising details.
Learn the definition first, then one example that makes the definition concrete.
Connect Yakult to a quantity you can measure, compute or draw — that is where exam questions come from.
Reproduce the core statement of Yakult from memory before moving on to harder problems.

Reference excerpt

Yakult (ヤクルト, Yakuruto) is a Japanese sweetened probiotic milk beverage fermented with the bacteria strain Lacticaseibacillus casei Shirota. It is sold by Yakult Honsha based in Tokyo. The name "Yakult" was coined from jahurto, an Esperanto word meaning "yogurt".

Ingredients Yakult's ingredients are water, skimmed milk, glucose-fructose syrup, sucrose, natural flavors (citrus), and live Lacticaseibacillus casei Shirota bacteria. The strain was originally classified as being Lactobacillus casei. Yakult is prepared by adding glucose to skimmed milk and heating the mixture at 90 to 95 °C for about 30 minutes. After letting it cool down to 45 °C, the mixture is inoculated with the lactobacillus and incubated for 6 to 7 days at 37 to 38 °C. After fermentation, water, sugar, gums, and lactic acid are added. It is produced with various flavors. In Singapore, from 1980 to 2026, it was sold in the orange, grape, apple and original flavors, but from July 2026, the orange flavor was discontinued and replaced with the peach flavor due to production capacity constraints. The muscat flavor is produced in Mexico and China, while the mango flavor is sold in Indonesia and India.

Health claims

In 2006, a panel appointed by the Netherlands Nutrition Center (Voedingscentrum) to evaluate a marketing request by Yakult found sufficient evidence to justify claims that drinking at least one bottle of Yakult per day might help improve bowel movements for people who tend to be constipated and might help maintain a healthy population of gut flora. However, these claims are not approved as health claims under EU regulations, which require authorization by the European Food Safety Authority (EFSA). The Netherlands Nutrition Center does not endorse specific probiotic products like Yakult, as only one probiotic health claim is authorized in the EU: that live bacteria in yogurt or fermented milk improve lactose digestion in individuals with lactose maldigestion. This claim is exclusive to yogurt and fermented milk containing specific strains (Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus). EFSA has rejected most probiotic health claims, including those for strains not in yogurt or fermented milk. In 2010, an EFSA panel decided that the company was not allowed to make the health claim that the product defends the upper respiratory tract against pathogens (and thus protects against diseases like the common cold), finding that this was not supported by evidence. In 2013, the UK Advertising Standards Authority disallowed an advertisement for Yakult in response to a complaint. It found that while there was sufficient evidence for the claim that "significant numbers of viable [Lactobacillus] survived transit to the gut [after consumption of Yakult]", the advertisement had made claims of general health benefits without providing a specific, referenced claim, as required.

Marketing history

Yakult was invented in 1935 in Japan by Minoru Shirota, who helped found the company Yakult Honsha for the purpose of commercializing it. Although Yakult is sold in Japan in supermarkets and convenience stores, it is also sold door-to-door in Japan, Asia, and Latin America in convenience stores.

History In 1930, scientist Minoru Shirota strengthened and cultured the Lactobacillus casei Shirota strain. Five years later, in 1935, Yakult began production in Japan. The company continued to expand, and in 1955, Yakult Honsha was established. In 1963, Yakult introduced a home delivery service, employing "Yakult ladies" to distribute the product directly to consumers. The following year, Yakult expanded internationally, beginning sales in Taiwan. In 1968, the company opened its first factory outside Japan in São Bernardo do Campo, Brazil. This international growth continued in 1969 with the establishment of the Hong Kong Yakult Co Ltd and the founding of Korea Yakult in South Korea. By 1981, Yakult had entered the Mexican market, opening a factory in the city of Ixtapaluca under the direction of Carlos Kasuga. Further expansion took place in 1994, with the product becoming available in Australia, Great Britain, and the United States. In 2004, Yakult launched sales in New Zealand through its Australian operations. That same year, Yakult LIGHT was introduced in Australia, offering a lower-sugar alternative. In 2017, the company reformulated Yakult LIGHT to further reduce sugar and energy content, replacing sugar with Stevia. In 2014, the company opened its first manufacturing facility in the United States, located in Fountain Valley, California.

Relationship with Danone In February 2018, it was reported that Danone planned to sell US$1.9 billion of its Yakult investment, reducing its stake from 21% to 7%. Following the report, there was a decline in Yakult's share value. Danone had first bought shares in Yakult in April 2000. The sale was completed in March 2018.

In mass media In September 2018, it was reported that the appearance of unlabelled Yakult bottles in the 2018 film To All the Boys I've Loved Before led to a rise in the drink's sales that coincided with a 2.8% increase in share price following the film's release on 17 August. In January 2020, professional sumo wrestler Takakeishō Takanobu appeared in a television commercial advertising Yakult 1000.

Illustrations

Worked examples

Example 1 — a first encounter with Yakult

Start with the simplest possible case. Write down what Yakult claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In science, the smallest case is usually a single object, a single equation or a single measurement. Check that every symbol or term in your sentence has a meaning in that case.

Example 2 — changing one variable

Take the situation from Example 1 and change exactly one quantity: double it, halve it, or set it to zero. Predict what should happen to Yakult before you calculate. Comparing your prediction with the result is the fastest way to find out whether you understand the idea or only the words.

Example 3 — an exam-style question

Typical questions about Yakult ask you to (a) state it precisely, (b) apply it to given data, and (c) explain a limitation. Practise writing all three answers in under five minutes; the third part is what separates a full-mark answer from an average one.

Applications of Yakult

In research: Yakult appears in science research whenever the underlying quantities have to be modelled precisely. Papers usually cite it as a starting assumption and then explore where it breaks down.
In technology and industry: Engineering practice reuses Yakult in design rules, simulations and safety margins. Knowing the idea lets you read a specification sheet and understand why the numbers look the way they do.
In the classroom: Yakult is common in secondary-school and first-year university syllabi. It links to neighbouring topics Fermented dairy products, Food and drink introduced in 1935, Japanese drink brands, so understanding it makes those chapters shorter.
In everyday life: Look for Yakult outside the textbook — in sport, cooking, traffic, electronics or the sky above you. An example you found yourself is remembered far longer than one you were given.

How to study Yakult in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what Yakult means in your own words.
Compare your version with the excerpt and mark what you missed.
Work through the three examples above with pen and paper.
Explain Yakult out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is Yakult in simple terms?

Yakult (ヤクルト, Yakuruto) is a Japanese sweetened probiotic milk beverage fermented with the bacteria strain Lacticaseibacillus casei Shirota. It is sold by Yakult Honsha based in Tokyo.

Why does Yakult matter?

Because it connects several science ideas at once: it gives you a definition you can apply, a quantity you can calculate, and a way to check whether a result is plausible.

How should I study Yakult?

Read the excerpt, restate it from memory, then work through the examples and applications listed on this page. The five-step study plan above takes about twenty minutes.

What does this page cover?

It gives you a compact reference excerpt plus original lgStudy explanations, examples, applications and study material on Yakult.