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Methylphenidate (MPH) has been previously shown to increase resting energy expenditure (REE) in individuals of normal weight; however, the effects on individuals living with obesity are currently unknown. Ten individuals living with obesity were randomly assigned to undergo 60 days of MPH administration with a daily dose of 0.5 mg/kg body weight or a placebo control. REE was measured before and after the 60‐day intervention. There was a trend toward significance for group × time interaction on REE (p = 0.082) with a large effect size (η2 = 0.331), with MPH administration increasing REE compared to a decrease in placebo control. Preliminary findings from this pilot study show that MPH has the potential to counter the adaptive thermogenic process commonly seen in weight loss. This is a unique finding among pharmacotherapies, as no approved obesity drugs measurably impact REE. [ABSTRACT FROM AUTHOR]

Summary: A systematic search was conducted in Medline Ovid, Embase, Scopus, and Cochrane Central Register of Controlled Trials up until March 2021 following PRISMA guidelines. Studies included evaluated ghrelin, GLP‐1, PYY or appetite sensation via visual analogue scales (VASs) before and after Roux‐en‐Y gastric bypass (RYGB) in adults. A multilevel model with random effects for study and follow‐up time points nested in study was fit to the data. The model included kcal consumption as a covariate and time points as moderators. Among the 2559 articles identified, k = 47 were included, among which k = 19 evaluated ghrelin, k = 40 GLP‐1, k = 22 PYY, and k = 8 appetite sensation. Our results indicate that fasting ghrelin levels are decreased 2 weeks post‐RYGB (p = 0.005) but do not differ from baseline from 6 weeks to 1‐year post‐RYGB. Postprandial ghrelin and fasting GLP‐1 levels were not different from pre‐surgical values. Postprandial levels of GLP‐1 increased significantly from 1 week (p < 0.001) to 2 years post‐RYGB (p < 0.01) compared with pre‐RYGB. Fasting PYY increased at 6 months (p = 0.034) and 1 year (p = 0.029) post‐surgery; also, postprandial levels increased up to 1 year (p < 0.01). Insufficient data on appetite sensation were available to be meta‐analyzed. [ABSTRACT FROM AUTHOR]

There has been much consideration over whether exogenous ketone bodies have the capacity to enhance exercise performance through mechanisms such as altered substrate metabolism, accelerated recovery, or neurocognitive improvements. This systematic review aimed to determine the effects of both ketone precursors and monoesters on endurance exercise performance. A systematic search was conducted in PubMed, SPORTDiscus, and CINAHL for randomized controlled trials investigating endurance performance outcomes in response to ingestion of a ketone supplement compared to a nutritive or nonnutritive control in humans. A meta-analysis was performed to determine the standardized mean difference between interventions using a random-effects model. Hedge's g and 95% confidence intervals (CI) were reported. The search yielded 569 articles, of which eight were included in this review (80 participants; 77 men and three women). When comparing endurance performance among all studies, no significant differences were found between ketone and control trials (Hedges g = 0.136; 95% CI [−0.195, 0.467]; p =.419). Subanalyses based on type of endurance tests showed no significant differences in time to exhaustion (Hedge's g = −0.002; 95% CI [−0.312, 0.308]; p =.989) or time trial (Hedge's g = 0.057; 95% CI [−0.282, 0.395]; p =.744) values. Based on these findings, exogenous ketone precursors and monoesters do not exert significant improvements on endurance exercise performance. While all studies reported an increase in blood ketone concentrations after ingestion, ketone monoesters appear to be more effective at raising concentrations than precursors. [ABSTRACT FROM AUTHOR]

Summary: A dysbiotic intestinal microbiome has been linked to chronic diseases such as obesity, which may suggest that interventions that target the microbiome may be useful in treating obesity and its complications. Appetite dysregulation and chronic systemic low‐grade inflammation, such as that observed in obesity, are possibly linked with the intestinal microbiome and are potential therapeutic targets for the treatment of obesity via the microbiome. Dietary pulses (e.g., common beans) are composed of nutrients and compounds that possess the potential to modulate the gut microbiota composition and function which can in turn improve appetite regulation and chronic inflammation in obesity. This narrative review summarizes the current state of knowledge regarding the connection between the gut microbiome and obesity, appetite regulation, and systemic and adipose tissue inflammation. More specifically, it highlights the efficacy of interventions employing dietary common beans as a means to improve gut microbiota composition and/or function, appetite regulation, and inflammation in both rodent obesity and in humans. Collectively, results presented and discussed herein provide insight on the gaps in knowledge necessary for a comprehensive understanding of the potential of beans as a treatment for obesity while highlighting what further research is required to gain this understanding. [ABSTRACT FROM AUTHOR]

Reinforcing Relative Value (RRV) of food and impulsivity are associated with energy intake and obesity. This study investigated the degree to which changes in RRV and impulsivity independently or interactively predict changes in body weight and composition in women with overweight or obesity engaged in either fast or slow weight loss programs. Body weight, body composition, impulsivity (Barratt Impulsiveness Scale), and RRV snack (computerized Behavioural Choice Task) were measured at baseline and post-intervention in 30 women with obesity undergoing either slow (n = 14, –500 kcal/day, 20 weeks) or fast (n = 16, –1000 kcal/day, 10 weeks) weight reduction. No group × time effects were noted on body composition, impulsivity, or RRV, so participants from both groups were pooled for analysis. Multiple regression analyses indicated that none of the impulsivity variables predicted weight or fat mass (FM) loss. However, ΔRRV snack predicted ΔFM (r = 0.40, p = 0.046), whereby greater increases in RRV snack were associated with less FM loss. The results indicate that different rates of weight loss do not differentially affect RRV snack or impulsivity traits. However, changes in RRV snack predicted FM loss, suggesting that dietary interventions that either mitigate increases or foster reductions in the RRV snack may yield greater reductions in adiposity. Trial Registration clinicaltrials.gov identifier: NCT04866875. Novelty: No differences in RRV of food were noted between fast and slow weight loss. Weight loss from combined fast and slow groups led to a moderate-sized reduction in total impulsivity. Greater diet-induced increases in RRV snacks were associated with less body fat loss. [ABSTRACT FROM AUTHOR]