Published : 04 Oct 2026, 11:51 PM
Updated : 04 Oct 2026, 11:51 PM
A two-year randomised clinical trial has found that diet soft drinks can be as effective as water for long-term weight loss and maintenance among adults with overweight or obesity, according to ScienceDaily.
The trial involved 493 adults who took part in a structured behavioural weight-management programme. Participants were assigned to drink either water or beverages sweetened with non-nutritive sweeteners such as aspartame, acesulfame-K and sucralose.
ScienceDaily reported that Researchers at the University of Liverpool found that both groups reduced their weight over the 104-week study. Those drinking diet beverages lost an average of 4.8kg, compared with 3.7kg among those drinking water, although the difference was not statistically significant.
Both groups also maintained their weight reductions through the second year, when the structured programme no longer provided additional assistance.
The University of Liverpool said participants in both groups also recorded improvements in waist and hip measurements, body composition and several metabolic markers, cited per the report.
There were no clinically meaningful differences between the groups in blood pressure or cholesterol levels. Researchers also found no evidence that diet drinks increased appetite or caused significant metabolic harm.
The study team noted that sugar consumption fell in both groups, with a slightly greater reduction among those drinking beverages containing non-nutritive sweeteners.
Professor Jo Harrold of the University of Liverpool, who led the study, said concerns that sweeteners could disrupt appetite or promote weight gain were not supported by the long-term randomised trial.
Professor Jason Halford of the University of Leeds, formerly of Liverpool, said the findings suggested diet drinks could provide an alternative to sugar-sweetened beverages while producing weight-management outcomes similar to water, reported ScienceDaily.
The study, published in the British Journal of Nutrition, was funded by the American Beverage Association, while researchers said they remained independent in analysing and reporting the findings.
The results could add to debate over WHO guidance, stated in the report, which advises against using non-sugar sweeteners for weight control because of uncertainty from observational studies.
Liverpool researchers said the new randomised evidence could help inform future guidance and public health policy.
