Sugar-sweetened or artificially sweetened beverage consumption, physical activity and risk of type 2 diabetes in US adults.

Aims/hypothesis: A positive association between sugar-sweetened beverages (SSBs) and diabetes risk has been shown, with inconsistent evidence between artificially sweetened beverages (ASBs) and diabetes. Moreover, it is uncertain if physical activity can mitigate the negative effects of these beverages on diabetes development. Therefore, we aimed to evaluate the independent and joint associations between SSB or ASB consumption and physical activity on the risk of type 2 diabetes.

Enactment, Evaluation, and Expansion of a Healthy Living Club in an Out of School Setting: A Community-Academic Partnership.

Interventions in community settings, where children spend substantial out of school time, may enhance access to evidence-based lifestyle interventions. The Boys and Girls Club of Lawrence (BGCL) and New Balance Foundation Obesity Prevention Center at Boston Children's Hospital partnered to revise, enact, and evaluate BGCL's existing Healthy Living Club and then flexibly expand the program to increase access. The BGCL is within walking distance of three public housing communities and easily accessible to members, of whom 90% identify as Hispanic.

Design and conduct of a randomized controlled feeding trial in a residential setting with mitigation for COVID-19.

Background: Evaluating effects of different macronutrient diets in randomized trials requires well defined infrastructure and rigorous methods to ensure intervention fidelity and adherence.

Methods: This controlled feeding study comprised two phases. During a Run-in phase (14-15 weeks), study participants (18-50 years, BMI, ≥27 kg/m) consumed a very-low-carbohydrate (VLC) diet, with home delivery of prepared meals, at an energy level to promote 15 ± 3% weight loss.

Physiologic Adaptation to Macronutrient Change Distorts Findings from Short Dietary Trials: Reanalysis of a Metabolic Ward Study.

An influential 2-wk cross-over feeding trial without a washout period purported to show advantages of a low-fat diet (LFD) compared with a low-carbohydrate diet (LCD) for weight control. In contrast to several other macronutrient trials, the diet order effect was originally reported as not significant. In light of a new analysis by the original investigative group identifying an order effect, we aimed to examine, in a reanalysis of publicly available data (16 of 20 original participants; 7 female; mean BMI, 27.

Sugar- or artificially-sweetened beverage consumption, physical activity, and risk of cardiovascular disease in US adults.

Background: The extent to which physical activity attenuates the detrimental effects of sugar (SSBs)- or artificially-sweetened beverages (ASBs) on the risk of cardiovascular disease is unknown.

Methods: We used Cox proportional-hazards models to calculate hazard ratios and 95% confidence interval [HR (CI)] between SSB or ASB intake and physical activity with cardiovascular disease risk among 65,730 women in the Nurses' Health Study (1980-2016) and 39,418 men in the Health Professional's Follow-up Study (1986-2016), who were free from chronic diseases at baseline. SSBs and ASBs were assessed every 4-years and physical activity biannually.

Evidence for the carbohydrate-insulin model in a reanalysis of the Diet Intervention Examining The Factors Interacting with Treatment Success (DIETFITS) trial.

Background: The Diet Intervention Examining The Factors Interacting with Treatment Success (DIETFITS) trial demonstrated that meaningful weight loss can be achieved with either a "healthy low-carbohydrate diet" (LCD) or "healthy low-fat diet" (LFD). However, because both diets substantially decreased glycemic load (GL), the dietary factors mediating weight loss remain unclear.

Objectives: We aimed to explore the contribution of macronutrients and GL to weight loss in DIETFITS and examine a hypothesized relationship between GL and insulin secretion.

Monitoring body composition change for intervention studies with advancing 3D optical imaging technology in comparison to dual-energy X-ray absorptiometry.

Background: Recent 3-dimensional optical (3DO) imaging advancements have provided more accessible, affordable, and self-operating opportunities for assessing body composition. 3DO is accurate and precise in clinical measures made by DXA. However, the sensitivity for monitoring body composition change over time with 3DO body shape imaging is unknown.

Are methods of estimating fat-free mass loss with energy-restricted diets accurate?

Background/objectives: Fat-free mass (FFM) often serves as a body composition outcome variable in weight loss studies. An important assumption is that the proportions of components that make up FFM remain stable following weight loss; some body composition models rely on these "constants". This exploratory study examined key FFM component proportions before and following weight loss in two studies of participants with overweight and obesity.

Grocery Delivery to Support Healthy Weight Gain Among Pregnant Young Women With Low Income: Protocol for a Randomized Controlled Trial.

Background: Excessive weight gain during pregnancy is associated with complications for both the mother and her infant including gestational diabetes, hypertensive disorders, operative delivery, and long-term obesity. A healthy diet during pregnancy promotes healthy gestational weight gain and determines fetal epigenetic programming in infants that impacts risk for future chronic disease.

Objective: This project will examine the impact of grocery delivery during pregnancy on the weight, diet, and health outcomes of young pregnant women and their infants.

Competing paradigms of obesity pathogenesis: energy balance versus carbohydrate-insulin models.

The obesity pandemic continues unabated despite a persistent public health campaign to decrease energy intake ("eat less") and increase energy expenditure ("move more"). One explanation for this failure is that the current approach, based on the notion of energy balance, has not been adequately embraced by the public. Another possibility is that this approach rests on an erroneous paradigm.

A high-carbohydrate diet lowers the rate of adipose tissue mitochondrial respiration.

Adipocyte mitochondrial respiration may influence metabolic fuel partitioning into oxidation versus storage, with implications for whole-body energy expenditure. Although insulin has been shown to influence mitochondrial respiration, the effects of dietary macronutrient composition have not been well characterized. The aim of this exploratory study was to test the hypothesis that a high-carbohydrate diet lowers the oxygen flux of adipocyte mitochondria ex vivo.

Prolonged Glycemic Adaptation Following Transition From a Low- to High-Carbohydrate Diet: A Randomized Controlled Feeding Trial.

Objective: Consuming ≥150 g/day carbohydrate is recommended for 3 days before an oral glucose tolerance test (OGTT) for diabetes diagnosis. For evaluation of this recommendation, time courses of glycemic changes following transition from a very-low-carbohydrate (VLC) to high-carbohydrate diet were assessed with continuous glucose monitoring (CGM).

Research Design And Methods: After achieving a weight loss target of 15% (±3%) on the run-in VLC diet, participants (18-50 years old, BMI ≥27 kg/m2) were randomly assigned for 10 weeks to one of three isoenergetic diets: VLC (5% carbohydrate and 77% fat); high carbohydrate, high starch (HC-Starch) (57% carbohydrate and 25% fat, including 20% refined grains); and high carbohydrate, high sugar (HC-Sugar) (57% carbohydrate and 25% fat, including 20% sugar).

Stimulated Insulin Secretion Predicts Changes in Body Composition Following Weight Loss in Adults with High BMI.

Background: The aim of obesity treatment is to promote loss of fat relative to lean mass. However, body composition changes with calorie restriction differ among individuals.

Objectives: The goal of this study was to test the hypothesis that insulin secretion predicts body composition changes among young and middle-age adults with high BMI (in kg/m2) following major weight loss.

Effects of a low-carbohydrate diet on insulin-resistant dyslipoproteinemia-a randomized controlled feeding trial.

Background: Carbohydrate restriction shows promise for diabetes, but concerns regarding high saturated fat content of low-carbohydrate diets limit widespread adoption.

Objectives: This preplanned ancillary study aimed to determine how diets varying widely in carbohydrate and saturated fat affect cardiovascular disease (CVD) risk factors during weight-loss maintenance.

Methods: After 10-14% weight loss on a run-in diet, 164 participants (70% female; BMI = 32.

The carbohydrate-insulin model: a physiological perspective on the obesity pandemic.

According to a commonly held view, the obesity pandemic is caused by overconsumption of modern, highly palatable, energy-dense processed foods, exacerbated by a sedentary lifestyle. However, obesity rates remain at historic highs, despite a persistent focus on eating less and moving more, as guided by the energy balance model (EBM). This public health failure may arise from a fundamental limitation of the EBM itself.