Effect of dietary protein content on weight gain, energy expenditure, and body composition during overeating: a randomized controlled trial.

Context: The role of diet composition in response to overeating and energy dissipation in humans is unclear.

Objective: To evaluate the effects of overconsumption of low, normal, and high protein diets on weight gain, energy expenditure, and body composition.

Design, Setting, And Participants: A single-blind, randomized controlled trial of 25 US healthy, weight-stable male and female volunteers, aged 18 to 35 years with a body mass index between 19 and 30.

Dynamic energy-balance model predicting gestational weight gain.

Background: Gestational weight gains (GWGs) that exceed the 2009 Institute of Medicine recommended ranges increase risk of long-term postpartum weight retention; conversely, GWGs within the recommended ranges are more likely to result in positive maternal and fetal outcomes. Despite this evidence, recent epidemiologic studies have shown that the majority of pregnant women gain outside the target GWG ranges. A mathematical model that predicts GWG and energy intake could provide a clinical tool for setting precise goals during early pregnancy and continuous objective feedback throughout pregnancy.

A Simple Model Predicting Individual Weight Change in Humans.

Excessive weight in adults is a national concern with over 2/3 of the US population deemed overweight. Because being overweight has been correlated to numerous diseases such as heart disease and type 2 diabetes, there is a need to understand mechanisms and predict outcomes of weight change and weight maintenance. A simple mathematical model that accurately predicts individual weight change offers opportunities to understand how individuals lose and gain weight and can be used to foster patient adherence to diets in clinical settings.

The fall in leptin concentration is a major determinant of the metabolic adaptation induced by caloric restriction independently of the changes in leptin circadian rhythms.

Context: Leptin is involved in the hormonal regulation of the reproductive, somatotropic, thyroid, and autonomic axes and ultimately in the regulation of energy balance. In parallel to the metabolic adaptation observed in response to caloric restriction (CR), plasma leptin concentrations are substantially decreased, suggesting a role for this hormone in the drop in energy expenditure beyond that predicted by the changes in body composition (metabolic adaptation).

Aim: The aim of the study was to explore the changes in 24-h leptin circadian rhythm in response to CR and to investigate the relationship between these changes and metabolic adaptation.

Lorcaserin for the treatment of obesity.

Obesity is a worldwide epidemic and there is an urgent need for the development of effective pharmacological therapies that target the metabolic and behavioral factors of body weight regulation. Serotonin (5-HT) has been implicated as a critical factor in the short-term (meal-by-meal) regulation of food intake and pharmaceutical companies have invested millions of dollars to discover and develop drug targets for the serotonergic pathway. Lorcaserin is a novel selective agonist of the 5-HT(2C) receptor for weight loss therapy.

Aerobic exercise in women with polycystic ovary syndrome improves ovarian morphology independent of changes in body composition.

In a prospective study, eight women with polycystic ovary syndrome completed 16 weeks of individualized aerobic exercise training. Independent of changes in body weight and adiposity there was a statistically significant increase in aerobic fitness and insulin sensitivity and a statistically significant decrease in the total number of follicles measured by magnetic resonance imaging.

Association of β-2 adrenergic agonist and corticosteroid injection in the treatment of lipomas.

Aim: The aim of this study was to evaluate the efficacy of isoproterenol and prednisolone in the treatment of subcutaneous lipomas.

Methods: The first experiment evaluated in vitro lipolysis induced by isoproterenol 10(-6) M alone and across a range of prednisolone concentrations to determine the optimal dose to maximize lipolysis. The second experiment evaluated lipolysis in a lipoma and subcutaneous fat by in vivo microdialysis in five subjects to isoproterenol 10(-6) M with and without prednisolone 10(-6) M.

Lorcaserin, a 5-HT(2C) receptor agonist, reduces body weight by decreasing energy intake without influencing energy expenditure.

Context: Lorcaserin, a selective 5-hydroxytryptamine (5-HT)(2C) receptor agonist, reduces body weight. It is unclear whether weight loss is due to reduced energy intake (EI) or also to enhanced energy expenditure (EE).

Objective: This study tested the effect of lorcaserin on EI and EE.

Effect of caloric restriction with and without exercise on metabolic intermediates in nonobese men and women.

Objectives: The objective of the study was to evaluate whether serum concentrations of metabolic intermediates are related to adiposity and insulin sensitivity (Si) in overweight healthy subjects and compare changes in metabolic intermediates with similar weight loss achieved by diet only or diet plus exercise.

Design: This was a randomized controlled trial.

Participants And Intervention: The cross-sectional study included 46 (aged 36.

A computational model to determine energy intake during weight loss.

Background: Energy intake (EI) during weight loss is difficult and costly to measure accurately.

Objective: The objective was to develop and validate a computational energy balance differential equation model to determine individual EI during weight loss.

Design: An algorithm was developed to quantify EI during weight loss based on a validated one-dimensional model for weight change.

Caloric restriction in humans: impact on physiological, psychological, and behavioral outcomes.

The current societal environment is marked by overabundant accessibility of food coupled with a strong trend of reduced physical activity, both leading to the development of a constellation of disorders, including central obesity, insulin resistance, dyslipidemia, and hypertension (metabolic syndrome). Prolonged calorie restriction (CR) has been shown to extend both the median and maximal lifespan in a variety of lower species such as yeast, worms, fish, rats, and mice. Mechanisms of this CR-mediated lifespan extension are not fully elucidated, but possibly involve significant alterations in energy metabolism, oxidative damage, insulin sensitivity, inflammation, and functional changes in both the neuroendocrine and sympathetic nervous systems.

Reduced oxygenation in human obese adipose tissue is associated with impaired insulin suppression of lipolysis.

Context: Adipose tissue in obese individuals is characterized by reduced capillary density and reduced oxygenation.

Objective: Our objective was to test whether hypoxia is associated with reduced antilipolytic effect of insulin.

Participants, Design, And Setting: Twenty-one lean and obese individuals participated in this cross-sectional study at a university-based clinical research center.

Caloric restriction with or without exercise: the fitness versus fatness debate.

Unlabelled: There is a debate over the independent effects of aerobic fitness and body fatness on mortality and disease risks.

Purpose: To determine whether a 25% energy deficit that produces equal change in body fatness leads to greater cardiometabolic benefits when aerobic exercise is included.

Methods: Thirty-six overweight participants (16 males/20 females) (39 +/- 1 yr; 82 +/- 2 kg; body mass index = 27.

The effect of caloric restriction interventions on growth hormone secretion in nonobese men and women.

Lifespan in rodents is prolonged by caloric restriction (CR) and by mutations affecting the somatotropic axis. It is not known if CR can alter the age-associated decline in growth hormone (GH), insulin-like growth factor (IGF)-1 and GH secretion. To evaluate the effect of CR on GH secretory dynamics; forty-three young (36.

Aerobic exercise training improves atrial natriuretic peptide and catecholamine-mediated lipolysis in obese women with polycystic ovary syndrome.

Objective: The aim was to investigate the impact of polycystic ovary syndrome (PCOS) on the regulation of lipolysis by catecholamine and for the first time atrial natriuretic peptide (ANP) before and after 16 wk of aerobic training.

Patients: Eight hyperandrogenic obese women with PCOS [age, 25 +/- 1 yr; body mass index (BMI), 32.0 +/- 1.

Adiposity and comorbidities: favorable impact of caloric restriction.

The focus here is on research involving long-term calorie restriction (CR) to prevent or delay the incidence of the metabolic syndrome with age. The current societal environment is marked by overabundant accessibility of food coupled with a strong trend to reduced physical activity, both leading to the development of a constellation of disorders including central obesity, insulin resistance, dyslipidemia and hypertension (metabolic syndrome). Prolonged CR has been shown to extend median and maximal lifespan in a variety of lower species (yeast, worms, fish, rats, and mice).

Metabolic and behavioral compensations in response to caloric restriction: implications for the maintenance of weight loss.

Background: Metabolic and behavioral adaptations to caloric restriction (CR) in free-living conditions have not yet been objectively measured.

Methodology And Principal Findings: Forty-eight (36.8+/-1.

Reduced adipose tissue oxygenation in human obesity: evidence for rarefaction, macrophage chemotaxis, and inflammation without an angiogenic response.

Objective: Based on rodent studies, we examined the hypothesis that increased adipose tissue (AT) mass in obesity without an adequate support of vascularization might lead to hypoxia, macrophage infiltration, and inflammation.

Research Design And Methods: Oxygen partial pressure (AT pO2) and AT temperature in abdominal AT (9 lean and 12 overweight/obese men and women) was measured by direct insertion of a polarographic Clark electrode. Body composition was measured by dual-energy X-ray absorptiometry, and insulin sensitivity was measured by hyperinsulinemic-euglycemic clamp.

Endocrine alterations in response to calorie restriction in humans.

This review focuses on research involving calorie restriction (CR) in humans and the resulting changes observed in endocrine and neuroendocrine systems. Special emphasis is given to the clinical science studies designed to investigate the effects of controlled, high-quality, energy-restricted diets on both biomarkers of longevity and on the development of chronic diseases of human aging. Prolonged CR has been shown to extend both the median and maximal lifespan in a variety of lower species such as yeast, worms, fish, rats and mice.

Calorie restriction and bone health in young, overweight individuals.

Background: Calorie restriction (CR) is promoted to increase longevity, yet this regimen could lead to bone loss and fracture and therefore affect quality of life.

Methods: Forty-six individuals were randomized to 4 groups for 6 months: (1) healthy diet (control group); (2) 25% CR from baseline energy requirements (CR group); (3) 25% energy deficit by a combination of CR and increased aerobic exercise (CR + EX group); and (4) low-calorie diet (890 kcal/d; goal, 15% weight loss) followed by weight maintenance (LCD group). Bone mineral density (total body and hip by dual-energy x-ray absorptiometry) and serum bone markers (bone-specific alkaline phosphatase, osteocalcin, cross-linked C-telopeptide of type I collagen, and cross-linked N-telopeptide of type I collagen) were measured at baseline and after 6 months.