Background There are many benefits of maintaining healthy blood glucose levels, and studies have shown that lifestyle changes such as changes to diet can successfully restore normoglycaemia in participants with dysglycaemia. Significant health-related lifestyle changes are often difficult to implement and functional ingredients that can reduce glycaemic and insulaemic responses may help at risk populations. The aim of this study was to investigate whether a mulberry leaf extract could lower the glycaemic and insulinaemic responses to 75 g sucrose in healthy individuals. Methods A double-blind, randomised, placebo-controlled, crossover design trial was conducted by the Oxford Brookes Centre for Nutrition and Health. Thirty-eight participants were recruited into the trial and, after an overnight fast, were given 75 g sucrose + white mulberry leaf extract, or 75 g sucrose alone. Capillary blood samples were collected at 15-min intervals in the first hour and at 30-min intervals over the second hour to determine glucose and plasma insulin levels. Data analysis was conducted using a paired samples T test or a Wilcoxon signed rank test. Results The addition of mulberry leaf extract to sucrose resulted in a significantly lower glycaemic response and insulinaemic response compared to a matched placebo (sucrose alone). The change in blood glucose measurements were significantly lower at 15 min (p < 0.001), 30 min (p < 0.001), 45 min (p = 0.008), and 120 min (p < 0.001) and plasma insulin measurements were significantly lower at 15 min (p < 0.001), 30 min (p < 0.001), 45 min (p < 0.001), 60 min (p = 0.001) and 120 min (p < 0.001). The glucose iAUC (− 42%, p = 0.001), insulin iAUC (− 40%, p < 0.001), peak glucose (− 40.0%, p < 0.001) and peak insulin (− 41%, p < 0.001) from baseline were significantly lower for white mulberry leaf extract compared with the placebo. White mulberry leaf extract was well tolerated and there were no reported adverse events. Conclusions Mulberry leaf extract can be used as part of lifestyle changes that may lead to healthy blood glucose levels. Trial registration: ISRCTN99601810 (23 October 2020, retrospectively registered)

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The prevalence of obesity is rising, with current UK statistics indicating that 68 % of men and 58 % of women are classified as overweight or obese (1) . Consequently, effective weight management is of increasing importance and considerable attention is being placed on the use of functional ingredients in foods that are less energy dense and more satiating. The aim of this study was to investigate the effect of SlimBiome, a commercially available product, on food cravings and the responsiveness of individuals to the food environment, which are characteristics associated with hunger (2,3) , in overweight and obese women following standard nutritional advice. SlimBiome contains fibre (glucomannan), prebiotics and chromium, which have been shown to increase satiety and reduce energy intake, hunger and fat cravings in overweight and obese adults (4)(5)(6) .A double-blind, randomised, placebo-controlled study was conducted in 20 overweight and obese women over a 4-week period. Inclusion criteria included women aged 18-65 years, with a body mass index between 25-35 kg/m 2 , no significant health problems, and no history of dieting within the month prior to starting the study. Participants attended three study visits at week 0, week 1 and week 4. At week 0 they were randomly assigned to receive the test drink or placebo and were instructed to consume the drink three times a day for 4 weeks. At each visit, participants rated subjective sensations of appetite before and after consuming the test drink or placebo and completed the Control of Eating Questionnaire (CofEQ) (7) and the Power of Food Scale (POF) (8) . During the week 0 visit, standard nutritional advice based on the Eat Well Guide was provided to all participants. Differences in week 0 and week 4 POF Scale scores for both groups were assessed using Wilcoxon signed-rank tests. Differences between group week 4 CofEQ scores were assessed using analysis of covariance (ANCOVA), including baseline scores from week 0 as covariates.For the CofEQ, ratings in response to 'How hungry have you felt?' at week 4 were significantly lower in the treatment group compared to the placebo group (P = 0·034). No significant differences were observed between the groups at week 4 for CofEQ items assessing frequency or strength of food cravings (P > 0·05 for all items). For the POF Scale, scores decreased significantly after the 4-week intervention period in both the placebo group (P = 0·035) and the treatment group (P = 0·007).In conclusion, subjective feelings of hunger measured by the CofEQ were significantly reduced in women who consumed SlimBiome compared to placebo. Although cravings appeared to subside more in women consuming SlimBiome, no significant difference was seen compared to placebo. This may be due to both groups becoming less responsive to the food environment, a characteristic shown to predict strength of and ability to resist cravings (3) .