Study details and key findings

On social media, sparkling water has been a trending topic due to its potential impact on weight. One common theory is that carbonated water can increase feelings of fullness while water itself can help the body burn fat by boosting metabolism.

In the study, researchers examined whether sparkling water could lower blood glucose levels, which could then contribute to weight loss. According to health experts, keeping blood sugar levels steady, with few spikes or dips, can help the body's cells burn fat more effectively for energy.

The researchers found that after sparkling water is consumed, carbon dioxide travels through the stomach capillaries into the bloodstream. There, red blood cells use an enzyme called carbonic anhydrase to convert carbon dioxide to bicarbonate. This makes the inside of red blood cells more alkaline, which can then accelerate glycolysis, or the process of breaking down glucose to produce energy.

According to Akira Takahashi, a physician in the dialysis center at Tesseikai Neurosurgical Hospital in Japan and the study's author, the process is similar to how hemodialysis can lower blood sugar. During hemodialysis, carbon dioxide enters the blood like it does when sparkling water is consumed.

However, Takahashi noted that the overall effect was small and was unlikely to contribute meaningfully to weight loss.

"During a four-hour session of hemodialysis, only about 9.5g of glucose is consumed," Takahashi said. "Since drinking carbonated water provides CO₂ for a much shorter period than hemodialysis, its effect on glucose consumption is negligible and does not contribute to weight loss."

Lori Welstead, a registered dietitian who specializes in gastrointestinal nutrition at University of Chicago Medicine, expressed a similar sentiment, saying that "[s]ome people with a 'slow' stomach, so to speak, find carbonation helps with their gut motility."

However, Welstead noted that people should avoid drinking too much sparkling water since more than one or two cans a day could exacerbate gas and abdominal pain due to excess carbonation.

"If someone's coming in and they're saying, 'Oh my gosh, I'm gassy, I'm bloated, I'm burping, I'm feeling so sick all day,' it could be due to drinking five cans of carbonated water each day," Welstead said.

Overall, Jonathan Kaplan, founder and CEO of Dr. Well by BuildMyHealth, said "[d]inking fizzy water is just part of the equation for effective weight loss" and that "[i]t could be used as an alternative to high-calorie drinks, but to achieve real progress, it must be used in conjunction with diet and exercise."

Kaplan recommends that people eat a diet with plenty of lean proteins, fiber, and healthy fat to feel full longer and help maintain muscle while losing fat. Regular exercise, stress management, and good sleep will also have a beneficial effect on your weight-loss efforts.

Separately, Zeagler recommended that people practice mindful eating — including paying attention to their hunger cues, eating slowly, and avoiding distractions during meals — or track their progress with a food journal, app, or wearable device.

"This way, you can identify areas for improvement and improve upon them," she said. "Remember, you can't improve what you don't measure."