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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).

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Background Although fructose as a source of excess calories increases uric acid, the effect of the food matrix is unclear. Objectives To assess the effects of fructose-containing sugars by food source at different levels of energy control on uric acid, we conducted a systematic review and meta-analysis of controlled trials. Methods MEDLINE, Embase, and the Cochrane Library were searched (through 11 January 2021) for trials ≥ 7 days. We prespecified 4 trial designs by energy control: substitution (energy-matched replacement of sugars in diets); addition (excess energy from sugars added to diets); subtraction (energy from sugars subtracted from diets); and ad libitum (energy from sugars freely replaced in diets) designs. Independent reviewers (≥2) extracted data and assessed the risk of bias. Grading of Recommendations, Assessment, Development, and Evaluation was used to assess the certainty of evidence. Results We included 47 trials (85 comparisons; N = 2763) assessing 9 food sources [sugar-sweetened beverages (SSBs), sweetened dairy, fruit drinks, 100% fruit juice, fruit, dried fruit, sweets and desserts, added nutritive sweetener, and mixed sources] across 4 energy control levels in predominantly healthy, mixed-weight adults. Total fructose-containing sugars increased uric acid levels in substitution trials (mean difference, 0.16 mg/dL;  95% CI:  0.06–0.27 mg/dL;  P = 0.003), with no effect across the other energy control levels. There was evidence of an interaction by food source: SSBs and sweets and desserts increased uric acid levels in the substitution design, while SSBs increased and 100% fruit juice decreased uric acid levels in addition trials. The certainty of evidence was high for the increasing effect of SSBs in substitution and addition trials and the decreasing effect of 100% fruit juice in addition trials and was moderate to very low for all other comparisons. Conclusions Food source more than energy control appears to mediate the effects of fructose-containing sugars on uric acid. The available evidence provides reliable indications that SSBs increase and 100% fruit juice decreases uric acid levels. More high-quality trials of different food sources are needed. This trial was registered at clinicaltrials.gov as NCT02716870.

Background: Fructose providing excess calories in the form of sugar sweetened beverages (SSBs) increases markers of non-alcoholic fatty liver disease (NAFLD). Whether this effect holds for other important food sources of fructose-containing sugars is unclear. To investigate the role of food source and energy, we conducted a systematic review and meta-analysis of controlled trials of the effect of fructose-containing sugars by food source at different levels of energy control on non-alcoholic fatty liver disease (NAFLD) markers. Methods and Findings: MEDLINE, Embase, and the Cochrane Library were searched through 7 January 2022 for controlled trials ≥7-days. Four trial designs were prespecified: substitution (energy-matched substitution of sugars for other macronutrients); addition (excess energy from sugars added to diets); subtraction (excess energy from sugars subtracted from diets); and ad libitum (energy from sugars freely replaced by other macronutrients). The primary outcome was intrahepatocellular lipid (IHCL). Secondary outcomes were alanine aminotransferase (ALT) and aspartate aminotransferase (AST). Independent reviewers extracted data and assessed risk of bias. The certainty of evidence was assessed using GRADE. We included 51 trials (75 trial comparisons, n = 2059) of 10 food sources (sugar-sweetened beverages (SSBs); sweetened dairy alternative; 100% fruit juice; fruit; dried fruit; mixed fruit sources; sweets and desserts; added nutritive sweetener; honey; and mixed sources (with SSBs)) in predominantly healthy mixed weight or overweight/obese younger adults. Total fructose-containing sugars increased IHCL (standardized mean difference = 1.72 [95% CI, 1.08 to 2.36], p < 0.001) in addition trials and decreased AST in subtraction trials with no effect on any outcome in substitution or ad libitum trials. There was evidence of influence by food source with SSBs increasing IHCL and ALT in addition trials and mixed sources (with SSBs) decreasing AST in subtraction trials. The certainty of evidence was high for the effect on IHCL and moderate for the effect on ALT for SSBs in addition trials, low for the effect on AST for the removal of energy from mixed sources (with SSBs) in subtraction trials, and generally low to moderate for all other comparisons. Conclusions: Energy control and food source appear to mediate the effect of fructose-containing sugars on NAFLD markers. The evidence provides a good indication that the addition of excess energy from SSBs leads to large increases in liver fat and small important increases in ALT while there is less of an indication that the removal of energy from mixed sources (with SSBs) leads to moderate reductions in AST. Varying uncertainty remains for the lack of effect of other important food sources of fructose-containing sugars at different levels of energy control.

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Sugars containing fructose are emerging as the dominant public health targets for their role in the epidemic of overweight and obesity. This position is largely supported by ecological observations, rodent models of overfeeding and select human trials. Higher level evidence from systematic reviews and meta‐analyses of controlled dietary trials has yet to show convincingly that fructose‐containing sugars behave differently from any other forms of energy (especially refined starch and fat). Prospective cohort studies, which provide the strongest observational evidence, have shown an association between risk of overweight and obesity and fructose‐containing sugars consumed as sugar‐sweetened beverages but not as total sugars or other important sources of added sugars such as cakes, pastries and sweets. Comparative analyses show that high intakes of other highly palatable foods such as refined grains, processed meats, red meats, French fries and potato products, as well as physical inactivity may play an equal or greater role in weight gain and the risk of overweight and obesity. The contributions of these factors are also difficult to disentangle from that of sugar‐sweetened beverages owing to their collinearity with sugar‐sweetened beverages as part of a Western dietary pattern and lifestyle. Attention needs to remain focused on decreasing overconsumption of all foods associated with overweight and obesity. Sugar‐sweetened beverages and foods are certainly an important place to start but should not draw attention away from the issue of overconsumption in general.