The 2018 Netflix teen comedy To All the Boys I've Loved Before featured actor Noah Centineo taking gulps from a tiny bottle capped with red foil at the top. Characters referred to it as a “Korean yogurt smoothie," but on Twitter, it was quickly pointed out that this wasn't some fictional beverage made just for the movie—the tiny bottle with the distinct shape was based on Yakult, a probiotic drink that is a staple in plenty of lunchboxes in Japan, South Korea, the U.S., and other countries around the world.

Yakult shortages were soon being reported by Twitter users—but that wasn't necessarily a bad thing for the company, as its stock also climbed 2.6 percent in the two weeks after the movie came out in mid-August. But a brief cameo in a Netflix movie isn't the most interesting part of Yakult's backstory. Learn more about the rich history of this sweet, creamy beverage below.

Yakult's Origins

The production of Yakult (pronouned YAA-kult) began in the 1930s, after founder Dr. Minoru Shirota successfully cultured a specific strain of bacteria (known as Lactobacillus casei strain Shirota, or LcS) that has been shown to improve gut health. But the seeds of such an idea were planted decades before.

Dr. Shirota was born in 1899 in the small town of Iida, in the rural Nagano prefecture of Japan, where he witnessed outbreaks of infectious diseases like cholera and dysentery while growing up. According to Yakult, Shirota was motivated by this and decided to pursue a career in medicine [PDF]. In 1921, Shirota entered medical school at Kyoto Imperial University (now Kyoto University) and eventually earned his doctorate.

Shirota was particularly focused on preventive medicine, and doing research on bacteria and microorganisms that could bolster a person's health and reduce the occurrence of common illnesses, which were linked to poor hygiene and nutrition. During his research, he discovered that lactic acid bacteria helps control bad bacteria in the gut. In 1930, he cultured LcS—a specific strain of bacteria that was strong enough to survive a person's digestive acids and reach the intestines alive, providing digestive health benefits in the process.

Five years later, in 1935, Shirota introduced an affordable fermented drink bolstered by this healthy bacteria to the Japanese market. He named his new drink Yakult, which comes from the Esperanto word jahurto, meaning yogurt, and it was part of Shirota’s vision of helping improve the health of people all over the world.

What does Yakult taste like?

Although the original recipe has been changed over the years, Yakult's primary ingredients still include water, skimmed milk, glucose, sugar, and of course, LcS. The actual flavor of the drink is a little harder to nail down. While the drink is fruity and somewhat milky, people have described its taste as "yogurt-y," while others consider it to be "sweet and sour," and detect notes of peach, citrus, and even apple. For what it's worth, Yakult's UK website described the flavor as “citrus and vanilla.”

Yakult's Cultural Significance

In 1955, Yakult Honsha was established to sell its flagship drink. As of 2020, about 40 million bottles [PDF] are sold daily in over 40 countries and regions (including Japan). The immense popularity of the product has created a culture around the iconic bottle and packaging, too.

In 1963, Yakult employed women to sell and deliver their products to individuals at home while traveling on bicycles, motorcycles, or other motorized vehicles. These women, often referred to as “Yakult ladies” or “Yakult aunties,” are as ubiquitous as mailmen or police in countries like Japan and Korea.

According to The New York Times, becoming a “Yakult lady” (or yakult ajumma) was one of the first jobs available to women outside the home in South Korea, helping supplement their household incomes and establish the country's dairy market. Sanae Ueno, head of Yakult in Indonesia, says the ideal Yakult lady is “aged over 30 and has children—because mothers tend to be more 'health conscious' and have a good network of other women to target as customers,” and that the key point in hiring is finding “women who understand the local culture, can communicate well, and who will keep to a regular schedule.”

The Yakult ladies were essential to the company's early marketing efforts, as Yakult hired local women to evangelize about the product's health benefits. The Yakult Ladies helped build brand trust and loyalty among consumers as they spoke about the product and how it could potentially help local communities. The success of the program is clear, as there are still Yakult ladies selling the product in their carts to this day.

Solidifying the brand's cultural significance, Yakult also purchased a baseball team in the Nippon Professional Baseball league in 1969. The Tokyo Yakult Swallows won their first Japan Series championship in 1978 and the team is a favorite of author Haruki Murakami, one of their most famous fans. Murakami even has a book, The Yakult Swallows Poetry Collection, which is inspired by the team.

Enjoying Yakult

While many people drink Yakult straight out of the iconic plastic bottle (which was introduced in 1968), there are a number of ways to enjoy this beverage.

Freezing the bottle is a quick way to make a granita, or take it an extra step further and get inspired by Yakult's own soft serve. You can also use Yakult as a sweet, probiotic add-in to smoothies and other drinks. In fact, one of the most popular ways of consuming Yakult for adults is as a cocktail. Yogurt soju is an extremely popular drink in Korea and in Koreantowns around the world, an adult way of consuming a childhood favorite for many.

Where To Find It

Yakult is available in most supermarkets. You can also find the product online on Amazon. If you're not as interested in the drink, there are also many Yakult-inspired items like gummy candy and a Yakult-shaped water bottle, which could be worth trying as well.

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