Science news from the 13th European Nutrition Conference – FENS 2019
- Choosing low/no calorie sweetened drinks can help frequent consumers maintain a good-tasting, enjoyable diet while aiming to control body weight, according to new studies.
- Comprehensive systematic reviews and meta-analyses of controlled human trials show potential for benefits of low/no calorie sweeteners in weight and glucose control, when used to replace sugars and calories in the diet.
- Low/no calorie sweeteners can be a helpful tool in food reformulation as they allow to replace sugar and reduce calories in foods and beverages while maintaining the pleasure of sweet taste.
Organised every four years, the 13th European Nutrition Conference – FENS 2019 gained the interest of top nutrition scientists from around the world who gathered in Dublin from 15th to 18th October 2019, where latest research in key nutrition areas, including sugar reduction, was presented and discussed. As the rates of obesity and non-communicable diseases (NCDs) continue to increase worldwide and calorie and sugar reduction have become public health priorities, the potential role of low/no calorie sweeteners in weight and diabetes control was one of the topics of high scientific interest.
In an ISA-organised scientific symposium entitled: “Low calorie sweeteners in the human diet: Scientific evidence and recommendations about their use and benefits”, Prof Jason Halford, University of Liverpool (UK), Prof Anne Raben, University of Copenhagen (Denmark), and Dr Margaret Ashwell OBE, Ashwell Associates (UK) presented recent research findings around this scientific subject. Recent systematic reviews, new studies exploring the behavioural factors relating to the consumption of low/no calorie sweeteners including diet beverages, and the outcomes of a 2018 experts’ workshop were presented at the symposium indicating that low/no calorie sweeteners can help people to reduce, or manage calorie intake, and in turn control their body weight, while keeping the enjoyment of a palatable diet. Thereby they allow people to align two potentially conflicting goals, in this case hedonic eating and successful weight control.
Why do consumers choose low/no calorie sweeteners?
Observational data have sometimes linked higher consumption of low/no calorie sweeteners to higher body weight and body mass index (BMI) but, as emphasised in a WHO-sponsored scoping review of literature by Lohner et al (2017), “a positive association between NNS [non-nutritive sweeteners] consumption and weight gain in observational studies may be the consequence of and not the reason for overweight and obesity.” Indeed, several studies have confirmed that consumers use low/no calorie sweeteners as a means to control their weight, and therefore it should be expected that they are used more often by people with higher BMI (Catenacci et al, 2014; Drewnowski and Rehm, 2016).
A new study by the University of Liverpool, presented by Prof Jason Halford at FENS 2019, further confirms this finding: people’s concern about their body weight and restraint eating patterns, for example following a calorie-restricted diet, have been indicated as key drivers for consuming low/no calorie sweetened beverages (Maloney et al, 2019). Other factors driving intake are consumers’ positive beliefs about the good taste (palatability) of diet drinks and about their potential help in appetite control.
Low/no calorie sweeteners may help align conflicting goals: hedonic eating and successful weight control
In a series of experiments, researchers from the University of Liverpool showed that consumption of low/no calorie sweetened beverages may help consumers to maintain a good-tasting diet while trying to successfully control their body weight, two concurrent but potentially conflicting goals (Maloney et al, 2019). The studies also found that some frequent consumers may use low/no calorie sweeteners as a successful strategy to control food intake and eat less (and fewer calories) when in a state of craving. While this finding was not confirmed for all individuals, indeed, frequent consumers felt more in control and less guilty about their eating when diet beverages were available, compared to when their favourite drink was unavailable.
Low/no calorie sweeteners do not raise blood glucose and insulin levels: outcomes of recent systematic reviews and meta-analysis
Reviewing the current literature and recent comprehensive systematic reviews and meta-analysis, Prof Anne Raben concluded that low/no calorie sweeteners have no effect on acute postprandial glycaemic (blood glucose levels) or insulinemic control (Tucker and Tan, 2017; Engel et al, 2018; Higgins et al, 2018; Nichol et al, 2018; Anker et al, 2019). An important benefit is that, when compared to sugars, low/no calorie sweeteners lead to a lower blood glucose rise (EFSA, 2011).
Furthermore, systematic reviews and meta-analysis looking into effects of low/no calorie sweeteners on calorie intake and body weight outcomes show that, when used to replace sugars, low/no calorie sweeteners can help in reduced energy intake, and thus in weight loss (Rogers et al, 2016; Toews et al, 2019). When compared to placebo, most systematic reviews find that low/no calorie sweeteners have no impact on body weight, as by themselves have no pharmacological-type weight loss effects (Sievenpiper et al, 2017; Anker et al, 2019).
On the basis of the available evidence, recommendations from diabetes-related organisations such as the American Diabetes Association (ADA) and Diabetes UK support that replacing added sugars with sugar alternatives, without caloric compensation, could decrease daily intake of carbohydrates and calories, and that these dietary changes could beneficially affect glycaemic, weight, and cardiometabolic control (Evert et al [ADA], 2019). They can therefore be used as part of a strategy in the management of weight and diabetes (Diabetes UK, 2018).
A helpful tool for food reformulation
Presenting the outcomes of an experts’ workshop, Dr Margaret Ashwell, reminded that reduction of sugars’ intake is being recommended globally to lower the risk and prevalence of obesity and that low/no calorie sweeteners can be one of the strategies to consider (Ashwell et al, publication under review). Low/no calorie sweeteners can be a helpful tool in food reformulation as they allow to replace sugar and reduce calories in foods, and especially in beverages, while maintaining the pleasure of sweet taste. Policies relating to sugar reduction and low/no calorie sweeteners differ among different countries. Efforts should be made to understand and, where possible, reconcile policy discrepancies by seeking common understanding of the role of low/no calorie sweeteners in the diet by policy makers, scientists and regulatory experts. It would also be helpful to review the regulatory hurdles that impede product development and reformulation designed to reduce sugars and calories.
Concluding, Dr Ashwell commented on the need to research and develop effective strategies to communicate evidence supporting the safety and efficacy of low/no calorie sweeteners. In an insightful discussion at the end of the symposium, the panel of speakers agreed with comments from the audience that there is a need for evidence-based communication to consumers and to health professionals.