Do low-calorie sweetened beverages help to control food cravings? Two experimental studies

You eye what you eat: BMI, consumption patterns, and dieting status predict temporal attentional bias to food-associated images

People know that overconsumption of high-fat high-sugar (HFHS) foods have negative consequences for physical and cognitive wellbeing but continue to consume these foods in excess, leading to recent proposals to model obesity as an addiction disorder. The current experiment tested, in a large undergraduate sample (N = 306), the hypothesis that obesity and overconsumption is linked with an oversensitivity to rewards that drives attentional biases towards foods and food-associated cues. Using a modified emotion-induced blindness task with food-related distractors, we examined the extent to which attentional biases to images of HFHS foods were accounted for by BMI, HFHS food intake, self-reported hunger, time since last meal, diet status, food preferences, and attentional control. We also examined whether the same individual differences predicted attentional priority to cues that have a learned association with HFHS foods (i.e., images of food logos). Contrary to our predictions, higher BMI predicted less attentional priority for images of food and food logos. At the same time, increased consumption of HFHS foods predicted increased attentional priority for food images, whereas dieting predicted increased attentional priority for food logo images. Our results suggest that different people may preferentially attend to food versus food logo imagery based on their relationships with food. More broadly, our results support the theoretical perspective that attentional biases to food-associated stimuli can be affected by various competing, state-related factors.

Knowledge and Perceptions of Non-Nutritive Sweeteners Within the UK Adult Population

Non-nutritive sweeteners (NNS) are popular sugar substitutes that can help in weight and diabetes management, but concerns regarding their use have been raised by the public. This study aimed to investigate knowledge, benefits and safety perceptions of NNS in a sample of UK adults. The impact of knowledge dissemination on the change in perceptions was also examined. An online survey was distributed through social media platforms and UK Universities and was completed by 1589 participants aged 18 years and above. Results showed a high-risk perception of NNS and a lack of knowledge in regulations in nearly half the population sample. The artificial attributes of NNS further limited their acceptance. Risk perception has been significantly linked to a lower consumption of sweeteners (p < 0.001) and was affected by gender, occupation, education levels, age and body weight status. Information dissemination significantly reduced risk perception and increased awareness of the benefits of NNS. Results suggest that developing effective communication strategies to educate consumers, potentially through trusted health government agencies and professional bodies, can help them to make informed choices. Education of health professionals could also be valuable in reassuring the public of the benefits of NNS.

Low-calorie sweeteners in the human diet: scientific evidence, recommendations, challenges and future needs. A symposium report from the FENS 2019 conference

Overconsumption of free sugars, particularly from sugar-sweetened beverages (SSB), has potential negative health impacts. Implementation of a range of public health strategies is needed to reduce intakes of free sugars, including reducing portion sizes, promoting healthier dietary choices and reformulating foods and beverages. Although low-calorie sweeteners (LCS) are a useful tool for reducing energy intake and control glucose response when consuming sweet foods and drinks, several opinions persist about the adverse health effects of LCS, many of which are based on poor, little or no scientific evidence. This symposium report summarises key messages of the presentations and related discussions delivered at a scientific symposium at the 13th European Nutrition Conference (FENS 2019). These presentations considered the scientific evidence and current recommendations about the use and potential benefits of LCS for human health, with a particular focus on current evidence in relation to body weight and glycaemic control. Many of the studies to date on LCS have focused on low-calorie sweetened beverages (LCSB); however, the psychological and behavioural factors influencing consumer beliefs and consumption of LCSB need to be further explored. Current recommendations for LCS use are described, including the conclusions from a recent expert consensus report identifying the challenges that remain with LCS research. Finally, existing knowledge gaps and future actions are described, as well as two large ongoing research projects: SWITCH and SWEET.

A rational review on the effects of sweeteners and sweetness enhancers on appetite, food reward and metabolic/adiposity outcomes in adults

Numerous strategies have been investigated to overcome the excessive weight gain that accompanies a chronic positive energy balance. Most approaches focus on a reduction of energy intake and the improvement of lifestyle habits. The use of high intensity artificial sweeteners, also known as non-caloric sweeteners (NCS), as sugar substitutes in foods and beverages, is rapidly developing. NCS are commonly defined as molecules with a sweetness profile of 30 times higher or more that of sucrose, scarcely contributing to the individual's net energy intake as they are hardly metabolized. The purpose of this review is first, to assess the impact of NCS on eating behaviour, including subjective appetite, food intake, food reward and sensory stimulation; and secondly, to assess the metabolic impact of NCS on body weight regulation, glucose homeostasis and gut health. The evidence reviewed suggests that while some sweeteners have the potential to increase subjective appetite, these effects do not translate in changes in food intake. This is supported by a large body of empirical evidence advocating that the use of NCS facilitates weight management when used alongside other weight management strategies. On the other hand, although NCS are very unlikely to impair insulin metabolism and glycaemic control, some studies suggest that NCS could have putatively undesirable effects, through various indirect mechanisms, on body weight, glycemia, adipogenesis and the gut microbiota; however there is insufficient evidence to determine the degree of such effects. Overall, the available data suggests that NCS can be used to facilitate a reduction in dietary energy content without significant negative effects on food intake behaviour or body metabolism, which would support their potential role in the prevention of obesity as a complementary strategy to other weight management approaches. More research is needed to determine the impact of NCS on metabolic health, in particular gut microbiota.

Effects of the Daily Consumption of Stevia on Glucose Homeostasis, Body Weight, and Energy Intake: A Randomised Open-Label 12-Week Trial in Healthy Adults

Stevia is a non-nutritive sweetener, providing sweet taste with no calories. This randomised, controlled, open-label 2-parallel arm trial examined the effects of daily stevia consumption on glycaemia in healthy adults. Secondary endpoints included body weight (BW) and energy intake (EI). Healthy participants (n = 28; aged 25 ± 5y, body mass index 21.2 ± 1.7 kg/m²) were randomised into either the stevia group (n = 14)—required to consume a stevia extract daily—or to the control group (n = 14). At weeks 0 and 12, the glucose and insulin responses to an oral glucose tolerance test were measured; BW and EI were assessed at weeks 0, 6, and 12. There was no significant difference in the glucose or insulin responses. There was a significant main effect of group on BW change (F(1,26) = 5.56, p = 0.026), as the stevia group maintained their weight as opposed to the control group (mean weight change at week 12: −0.22 kg, 95%CI [−0.96, 0.51] stevia group, +0.89 kg, 95%CI [0.16, 1.63] control group). The energy intake was significantly decreased between week 0 and 12 in the stevia group (p = 0.003), however no change was found in the control group (p = 0.973). Although not placebo-controlled, these results suggest that daily stevia consumption does not affect glycaemia in healthy individuals, but could aid in weight maintenance and the moderation of EI.