Sweeteners – friend or foe?
Given the contribution of dietary sugar to the development of obesity and cardio-metabolic disease, the World Health Organization has recommended that the intake of free sugars should be no more than 10 % of the total energy intake. As Jo Harrold, one of the coordinators of the SWEET project, explains: “Artificial/natural/non-nutritive/lower-calorie sweeteners, along with sweetness enhancers (S&SEs), provide an opportunity to remove calories in the form of sugar, while maintaining the appeal and commercial viability of popular products for the consumer.” Harrold, dean of Psychology and professor in Appetite and Obesity in the Department of Psychology at the University of Liverpool, was keen to identify what the risks and benefits are of using alternative sweeteners. The project also wanted to establish what barriers prevent their use. “All are approved for human consumption, but S&SEs are currently underutilised because, despite substantial safety data, some studies suggest links to increased risk of stroke and heart disease. Other research suggests they may have a negative impact on gut microbiota,” she says.
Clinical studies and surveys to establish impact of sugar alternatives
The team used a variety of protocols to study the effect of S&SEs, including acute (1 day) and repeated (14 days) dosing studies focusing on single food items to examine the impact of S&SEs on glycaemic response. They also considered feeding behaviour and blood biochemistry. Trials took place in adults recruited from Denmark, France, Spain and the United Kingdom. “At the centre of SWEET was the one-year randomised controlled trial (RCT) which investigated whether the prolonged use of S&SEs as part of a healthy, low-sugar diet could improve weight loss maintenance after rapid weight loss,” adds Harrold. The RCT considered the benefit-risk markers for Type 2 diabetes and cardiovascular diseases compared to no S&SE consumption. To do so, the trial recruited overweight or obese adults and children from Denmark, Greece, Spain and the Netherlands. The team also conducted an online survey of over 11 000 consumers in most EU Member States, to examine attitudes, perceptions and behavioural intentions towards S&SEs.
Avoidance of S&SEs mainly driven by perceived risks to health
Analyses indicated that consumers perceived the benefits of S&SEs to include weight loss, diabetes management and oral health. S&SEs from plant-based sources were more positively perceived than those from artificial sources. Avoidance of S&SEs is mainly driven by perceived risks to health. “However,” notes Harrold: “The short- and medium-term controlled interventions demonstrated that S&SEs in beverages, semi-solid and solid sweet food matrices support lower glycaemic responses, with no adverse impact on appetite, metabolic or health markers either acutely or after two weeks’ repeated daily consumption.” The long-term RCT demonstrated not only that replacing sugar in the whole diet with sweeteners improved weight loss control over the long term but importantly, but also that long-term use of sweeteners reduced cravings for sweet foods and did not raise the risks of Type 2 diabetes or cardiovascular disease. The team produced a decision support tool intended to promote the responsible development and use of sweeteners by industry, which will be accessible via an online interface on the SWEET project’s website. “We wanted to facilitate understanding and implementation of the project’s interventions and outcomes, and foster the adoption of commercial opportunities. This includes summaries written for non-expert readers,” Harrold says.
Keywords
SWEET, S&SEs, sweeteners, sugar alternatives, health, glycaemic response, blood biochemistry, diet
