A 20-year-old woman in Taiwan was hospitalized in 2023 after doctors removed over 300 kidney stones, a case reportedly linked to frequent bubble tea consumption in place of water, according to recent reports.
The popular beverage, which originated in Taiwan in the 1980s and has since spread globally, is facing increased scrutiny over potential health risks. Even as bubble tea shops have proliferated – with 6,635 across the United States in 2024 and projections for that number to double by 2028 – investigations are revealing concerns beyond its high sugar content.
Consumer Reports recently found elevated lead levels in bubble tea products sold in the United States, echoing previous warnings about foods made from cassava. Tapioca pearls, a signature component of bubble tea, are derived from cassava starch. Cassava plants are known to absorb heavy metals, including lead, from the soil, potentially contaminating the final product. Testing by Consumer Reports on pearls from major chains Gong Cha and Kung Fu Tea, as well as packaged boba from Trader Joe’s and WuFuYuan, revealed the presence of lead in all samples.
Although the lead levels detected weren’t high enough to warrant a complete avoidance of bubble tea, according to James E. Rogers, PhD, director of food safety research and testing at Consumer Reports, the findings highlight the necessitate for caution. Health experts emphasize that no amount of lead is considered safe, particularly for children and pregnant individuals.
Beyond lead contamination, the tapioca pearls themselves pose potential digestive risks. Their dense, starchy composition can slow stomach emptying, potentially leading to gastroparesis or, in rare cases, a complete blockage. Symptoms can include nausea, vomiting, and abdominal pain, with individuals already experiencing sluggish digestion being particularly vulnerable. Guar gum, a common thickener in bubble tea, may also contribute to constipation with frequent consumption.
The high sugar content of bubble tea – typically ranging from 20 to 50 grams per serving, comparable to or exceeding a can of Coca-Cola – is also a significant concern. Research in Taiwan found that regular bubble tea consumption by age nine was associated with a 1.7 times higher likelihood of developing cavities in permanent teeth. Public health experts in California have identified the drink as a contributing factor to rising obesity rates among young people.
The risks extend beyond physical health. Studies in China have linked frequent bubble tea consumption to higher rates of anxiety and depression in both children and adults. A study involving Chinese nurses found associations between regular bubble tea intake and anxiety, depression, fatigue, job burnout, and lower overall well-being, even after accounting for other factors. The same study noted fewer reported thoughts of suicide among those who consumed less bubble tea, though establishing a direct causal relationship remains challenging.
Medical professionals have also observed tapioca pearls appearing on imaging scans of patients hospitalized for unrelated conditions, such as car crashes or appendicitis. The pearls’ density can sometimes mimic kidney or gallstones, complicating diagnoses.
Pediatricians have long warned about the choking hazard posed by tapioca pearls, particularly for young children. A 19-year-old woman in Singapore died after inhaling three pearls while attempting to drink through a partially blocked straw, and similar incidents have been reported where quick intervention prevented tragedy.