Growing rates of obesity are becoming a global health threat. Many professionals note that excessive consumption of sugary beverages is a crucial contributor to weight gain and an increased risk of metabolic diseases. This evidence has informed many dietary guidelines that recommend water or drinks sweetened with non-caloric sweeteners to lower sugar intake and help maintain a healthy diet or to support weight loss.
However, not all recommendations include non-caloric sweeteners as an alternative; for instance, the World Health Organization (WHO) advises against them. To provide more for informed decision-making, the University of Liverpool ran the longest and most comprehensive randomized controlled trial on non-caloric sweetened beverages.
According to their study, published in the British Journal of Nutrition, non-nutritive drinks containing, for example, aspartame, acesulfame potassium, and sucralose, were compared with water in the context of long-term weight management.
“These latest findings show that concerns about sweeteners disrupting appetite or causing weight gain are not supported when tested in a rigorous, long-term randomised trial,” said study first author Joanne Harrold, dean of psychology at the University of Liverpool, in a news statement. “We hope this evidence informs future WHO guidance and public health policy.”
Non-Caloric Sweetened Beverages Impact on Appetite and Weight Loss
The trial, called “effectS of non-nutritive sWeetened beverages on appetITe during aCtive weigHt loss”, or SWITCH, aimed to examine how non-nutritive beverages perform as a way to reduce sugar consumption during weight loss and whether they affect appetite.
Explore All OptionsNon-caloric, or non-nutritive, beverages contain sweeteners instead of sugar, providing a low- or non-caloric alternative for people who want to abstain from their favorite soft drinks while trying to reduce their overall sugar intake. These non-nutritive sweeteners (NNS) include, for example, aspartame, saccharin, stevia and sucralose.
For the trial, the researchers followed close to 500 adults with overweight or obesity for two years during a behavioral weight management program. The study participants were randomly assigned to either consume water or common diet beverages. The research team found no evidence that NNS beverages have an impact on appetite regulation or long-term harm to metabolic health.
Read More: Tiny Hair Bundles Across Squid Skin May Help Explain Human Hearing Loss
Non-Sugar Beverages Perform Similarly to Water for Weight Loss and Metabolic Health
The team listed several outcomes when comparing the two groups. They saw that on average, participants in either group lost similar amounts of weight, which was maintained throughout the length of the trial. That included reduced waist and hip circumferences — which are key indicators of fat loss and body composition — and numerous metabolic biomarkers improved in both groups.
They also noted no significant difference in measures such as blood pressure and cholesterol after long-term consumption of either water or NNS beverages. Overall sugar intake dropped in both groups, with a slightly higher decrease among people who consumed the NNS beverages.
The authors suggest that the SWITCH trial provides additional evidence to inform future guidelines, especially since the WHO currently advises against non-sugar sweeteners for weight control or reducing the risk of noncommunicable diseases, such as type 2 diabetes or cardiovascular diseases.
Long-Term Clinical Studies on the Impact of NNS Beverages Have Been Lacking
One common concern about NNS beverages is the hypothesis that when a person consumes sweetness without the actual caloric input that normally accompanies sugar, the body’s association between sweetness and energy gets disrupted, which could lead to a reflex-like release of insulin that then impacts appetite, leading to overeating.
The authors, however, suggest that previous randomized controlled trials have shown beneficial or neutral effects of NNS beverages on body weight depending on what they are compared with, sugar-sweetened beverages or water, and note that research claiming NNS beverages have adverse health impacts derives mostly from short-term studies.
“This study provides the long‑term clinical evidence that has been missing from international discussions,” concluded co-study author Jason Halford from the University of Leeds and Liverpool in the statement. “For people trying to manage their weight, non‑nutritive sweetened beverages offer an effective alternative to sugar‑sweetened drinks — and perform equivalently to water over two years.”
Although the study was funded by the American Beverage Association, the research team said their research was conducted independently and without input from the funder.
This article is not offering medical advice and should be used for informational purposes only.
Article Sources
Our writers at Discovermagazine.com use peer-reviewed studies and high-quality sources for our articles, and our editors review for scientific accuracy and editorial standards. Review the sources used below for this article:
- This article references information from a study published in the British Journal of Nutrition: Effect of non-nutritive sweetened beverages v. water on body weight: long-term results of a randomised controlled trial
- This article references information from the WHO: WHO advises not to use non-sugar sweeteners for weight control in newly released guideline
