When a 30-year-old Seoulite surnamed Choi drops by the convenience store before hitting the gym, he makes sure that he chooses a sugar-free soft drink from the cooler.

“I have been drinking sugar-free soft drinks instead of regular ones, because I find it more helpful for my workouts,” he said.

Choi is one of many young health-conscious consumers whose choices reflect the clear winner in the beverage market -- sugar-free beverages.

Sugar-free and low-calorie soft drinks are enjoying their heyday in South Korea, with increasing sales and a growing variety of products.

According to South Korea’s leading beverage firm Lotte Chilsung, its sales of sugar-free soft drinks last year came to some 190 billion won ($144 million), up 111 percent on-year.

LG Household & Health Care, an exclusive manufacturer and distributor of Coca-Cola brand products in Korea, also said its sales of Coke Zero jumped 29 percent on-year.

The increase in sales of Coke Zero was much higher than those of regular Coke, which increased by only 6 percent on-year in 2022.

“Sales of Coke Zero only accounted for less than 10 percent of the combined sales of Coke products here until 2019. However, the proportion increased to 20 percent last year,” an official from LG Household & Health Care said.

Sugar-free rush, juice decline

The increasing local demand has prompted many companies develop and launch sugar-free versions of popular drinks.

This year alone, there were 10 sugar-free drinks newly introduced in the market, including Powerade Zero, Milkis Zero and Tams Zero.

Meanwhile, alongside the growing public appetite for sugar-free beverages, the demand for high-sugar fruit juice has been declining over the past few years in South Korea.

According to the Food Information Statistics System, the market size of juice products has been shrinking for the last four years. Sales of juice products in 2017 totaled 743 billion won, but the figure came down to 707 billion won in 2018, 692 billion won in 2019, 643.8 billion won in 2020 and 643.2 billion won in 2021.

“In my opinion, people no longer think that juice products have health benefits and are not worth their calories,” said Kim, a 31-year-old man who lives in Seoul.

Hidden long-term risks

Despite the growing popularity of sugar-free drinks, which are considered to be healthier options, some are still concerned if they would have negative long-term side effects.

According to a recent study published in late February in Nature Medicine, there are potential connections between the sweetener erythritol and cardiovascular events such as clotting, stroke, and heart attacks.

According to the study, which included 4,000 people from the US and Europe, people who had high levels of erythritol in their blood were more likely to suffer a major cardiac event within three years than those with lower levels.

"If your blood level of erythritol was in the top 25 percent compared to the bottom 25 percent, there was about a twofold higher risk for heart attack and stroke,” said Stanley Hazen, director of the Center for Cardiovascular Diagnostics and Prevention at the Cleveland Clinic Lerner Research Institute. Hazen added that the artificial sweetener is on par with the strongest of cardiac risk factors, like diabetes.