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Background: Obesity is a risk factor for developing several diseases, and although dietary pulses (nonoil seeds of legumes such as beans, lentils, chickpeas, and dry peas) are well positioned to aid in weight control, the effects of dietary pulses on weight loss are unclear. Objective: We summarized and quantified the effects of dietary pulse consumption on body weight, waist circumference, and body fat by conducting a systematic review and meta-analysis of randomized controlled trials. Design: We searched the databases MEDLINE, Embase, CINAHL, and the Cochrane Library through 11 May 2015 for randomized controlled trials of $3 wk of duration that compared the effects of diets containing whole dietary pulses with those of comparator diets without a dietary pulse intervention. Study quality was assessed by means of the Heyland Methodologic Quality Score, and risk of bias was assessed with the Cochrane Risk of Bias tool. Data were pooled with the use of generic inverse-variance random-effects models. Results: Findings from 21 trials (n = 940 participants) were included in the meta-analysis. The pooled analysis showed an overall significant weight reduction of 20.34 kg (95% CI: 20.63, 20.04 kg; P = 0.03) in diets containing dietary pulses (median intake of 132 g/d or w1 serving/d) compared with diets without a dietary pulse intervention over a median duration of 6 wk. Significant weight loss was observed in matched negative-energy-balance (weight loss) diets (P = 0.02) and in neutral-energy-balance (weightmaintaining) diets (P = 0.03), and there was low evidence of between-study heterogeneity. Findings from 6 included trials also suggested that dietary pulse consumption may reduce body fat percentage. Conclusions: The inclusion of dietary pulses in a diet may be a beneficial weight-loss strategy because it leads to a modest weight-loss effect even when diets are not intended to be calorically restricted. Future studies are needed to determine the effects of dietary pulses on long-term weight-loss sustainability. This protocol was registered at clinicaltrials.gov as NCT01594567.Am J Clin Nutr 2016;103:1213-23.

ObjectiveTo assess the effect of different food sources of fructose-containing sugars on glycaemic control at different levels of energy control.DesignSystematic review and meta-analysis of controlled intervention studies.Data sourcesMedine, Embase, and the Cochrane Library up to 25 April 2018.Eligibility criteria for selecting studiesControlled intervention studies of at least seven days’ duration and assessing the effect of different food sources of fructose-containing sugars on glycaemic control in people with and without diabetes were included. Four study designs were prespecified on the basis of energy control: substitution studies (sugars in energy matched comparisons with other macronutrients), addition studies (excess energy from sugars added to diets), subtraction studies (energy from sugars subtracted from diets), and ad libitum studies (sugars freely replaced by other macronutrients without control for energy). Outcomes were glycated haemoglobin (HbA1c), fasting blood glucose, and fasting blood glucose insulin.Data extraction and synthesisFour independent reviewers extracted relevant data and assessed risk of bias. Data were pooled by random effects models and overall certainty of the evidence assessed by the GRADE approach (grading of recommendations assessment, development, and evaluation).Results155 study comparisons (n=5086) were included. Total fructose-containing sugars had no harmful effect on any outcome in substitution or subtraction studies, with a decrease seen in HbA1c in substitution studies (mean difference −0.22% (95% confidence interval to −0.35% to −0.08%), −25.9 mmol/mol (−27.3 to −24.4)), but a harmful effect was seen on fasting insulin in addition studies (4.68 pmol/L (1.40 to 7.96)) and ad libitum studies (7.24 pmol/L (0.47 to 14.00)). There was interaction by food source, with specific food sources showing beneficial effects (fruit and fruit juice) or harmful effects (sweetened milk and mixed sources) in substitution studies and harmful effects (sugars-sweetened beverages and fruit juice) in addition studies on at least one outcome. Most of the evidence was low quality.ConclusionsEnergy control and food source appear to mediate the effect of fructose-containing sugars on glycaemic control. Although most food sources of these sugars (especially fruit) do not have a harmful effect in energy matched substitutions with other macronutrients, several food sources of fructose-containing sugars (especially sugars-sweetened beverages) adding excess energy to diets have harmful effects. However, certainty in these estimates is low, and more high quality randomised controlled trials are needed.Study registrationClinicaltrials.gov (NCT02716870).