Drinking lots of soda containing artificial sweeteners could raise the chance of developing liver cancer, a local study said.

Myung Seung-kwon, president of the Graduate School of Cancer Science and Policy at the National Cancer Center (family medicine department), and his Ph.D. student Alfred Jatho on Wednesday said they conducted a meta-analysis on 38 papers published in international journals between 2004 and 2019. Jatho is from Uganda, Africa.

A meta-analysis refers to combining the results of multiple studies addressing the same problem.

The research team performed the meta-analysis on 21 case-control studies and 17 cohort studies by searching literature in the medical database PubMed and EMBASE to investigate how soft drinks with artificial sweeteners are associated with the risk of gastrointestinal cancer such as colorectal cancer, esophageal cancer, stomach cancer, pancreatic cancer, and liver cancer.

The findings showed that there was no association between the overall risk of gastrointestinal cancer and soft drinks.

However, the sub-analysis on specific types of cancer showed that soda with artificial sweeteners raised the risk of liver cancer by 28 percent.

“Artificial sweeteners such as aspartame, saccharin, sucralose, neotame, and acesulfame are hundreds to thousands of times sweeter than sugar. They are used in soft drinks because they can reduce calories,” Myung said.

However, recent studies using cancer cell lines or tests on mice have shown that artificial sweeteners could cause cancer, he noted.

The meta-analysis showed that although most gastrointestinal cancers had no association with the intake of artificially sweetened soft beverages, liver cancer risk was higher in those who drank them, he went on to say.

An animal test in mice showed that aspartame, which is known to be about 200 times sweeter than sugar, could produce methanol and becomes subsequently metabolized as formaldehyde to cause liver cancer, he added.

Myung said his meta-analysis included only three related studies and required more studies to reach a clearer conclusion.

“It is still premature to conclude that soft drinks with artificial sweeteners increase the risk of liver cancer,” he said.

The study was published in the March issue of the Public Health Nutrition, an SCIE journal.