Carbonated Water, Said to Provide Fullness and Aid Weight Loss... But Research Shows Otherwise?

Drink in Moderation to Enjoy Metabolic Benefits

Carbonated water may help with weight loss by promoting glucose absorption and metabolism, but its effects are very minimal, according to a study.

Dr. Akira Takahashi of Teshikai Neurosurgery Hospital in Shijonawate City, Osaka, Japan, announced on the 22nd in the medical journal BMJ Nutrition Prevention & Health that he reached this conclusion by comparing the process of drinking carbonated water with haemodialysis.

Carbonated water is known to provide a feeling of fullness, speed up digestion, and help lower blood sugar levels, making it a potential diet aid. Dr. Takahashi pointed out that exactly how carbonated water lowers blood sugar and contributes to weight management has not been clearly identified. He also noted that the long-term effects of consuming large amounts of carbonated water are unknown.

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To investigate this, he compared the process of drinking carbonated water with haemodialysis, a treatment used when the kidneys cannot filter blood properly due to kidney disease, which removes waste and excess fluid from the blood using a dialysis machine. Haemodialysis alkalizes the blood and primarily produces carbon dioxide.

The research team explained that the carbon dioxide in carbonated water is absorbed through the stomach lining and rapidly converted into bicarbonate (HCO₃) in red blood cells. This alkalization process activates key enzymes in red blood cells, increasing the rate of glucose absorption and utilization. Observing changes in blood during haemodialysis, they found that initially, the glucose level in the dialysis fluid is high. However, as the blood passes through the dialysis machine, blood sugar levels decrease. Glucose levels dropped from 118.3 mg/dL before passing through the dialysis machine to 98.6 mg/dL afterward.

Dr. Takahashi stated that these results suggest carbonated water may indirectly promote weight loss by increasing the rate of glucose absorption and utilization. However, he noted that the amount of glucose used during a typical four-hour haemodialysis session is only about 9.5 g. He added, "Considering this minimal glucose reduction effect, the carbon dioxide effect of carbonated water is not a standalone weight loss therapy," emphasizing that "a balanced diet and regular physical activity remain sustainable and important factors for weight management."

He also said, "Carbonated water can affect the digestive system, especially in people with sensitive stomachs or gastrointestinal disorders, and may be associated with abdominal bloating, gas, irritable bowel syndrome, and worsening symptoms of gastroesophageal reflux disease." He added, "To enjoy the metabolic benefits of carbonated water while avoiding discomfort, it is important to consume it in moderation."

This content was produced with the assistance of AI translation services.