The link between eating rate and energy intake has long been a matter of extensive research. A better understanding of the effect of food intake speed on body weight and glycemia in the long term could serve as a means to prevent weight gain and/or dysglycemia. Whether a fast eating rate plays an important role in increased energy intake and body weight depends on various factors related to the studied food such as texture, viscosity and taste, but seems to be also influenced by the habitual characteristics of the studied subjects as well. Hunger and satiety quantified via test meals in acute experiments with subsequent energy intake measurements and their association with anorexigenic and orexigenic regulating peptides provide further insight to the complicated pathogenesis of obesity. The present review examines data from the abundant literature on the subject of eating rate, and highlights the main findings in people with normal weight, obesity, and type 2 diabetes, with the aim of clarifying the association between rate of food intake and hunger, satiety, glycemia, and energy intake in the short and long term.

Background/Objectives: Resting metabolic rate (RMR) is an important contributor of energy balance and displays a well-documented relationship with sex, age, race and fat-free mass (FFM) in the existing scientific literature. However, the impact of other body composition components such as fat and liver fat on RMR remains unclear. This study aims to investigate the correlation of RMR with body composition parameters in a sample of patients with overweight and obesity. Methods: Retrospective data of patients with overweight or obesity referred for magnetic resonance imaging of liver fat during the period 2018–2023 were utilized for this study. Demographic and anthropometric data were collected, including body composition parameters (body fat, muscle mass) and RMR measured by bioelectrical impedance and indirect calorimetry, respectively. Results: The final sample included 53 patients (66% male), with a mean age of 48 years (±11.2) and a mean body mass index (ΒΜΙ) of 38.5 kg/m² (32.7, 44.7). Simple correlation models revealed that RMR was separately correlated with gender, age, BMI, muscle mass, and liver fat (all p < 0.05) but not with fat mass. When multiple regression models were employed, only muscle mass retained its statistically significant influence on RMR, while total and hepatic fat did not significantly affect RMR after controlling for other parameters (gender, age, muscle mass). Conclusions: These findings confirm the known correlation between muscle mass and RMR while highlighting the lack of association between total and hepatic fat and RMR in individuals with overweight and obesity.

Purpose of Review: The development of long-acting incretin receptor agonists represents a significant advance in the fight against the concurrent epidemics of type 2 diabetes mellitus (T2DM) and obesity. The aim of the present review is to examine the cellular processes underlying the actions of these new, highly significant classes of peptide receptor agonists. We further explore the potential actions of multi-agonist drugs as well as the mechanisms through which gut-brain communication can be used to achieve long-term weight loss without negative side effects. Recent Findings: Several unimolecular dual-receptor agonists have shown promising clinical efficacy studies when used alone or in conjunction with approved glucose-lowering medications. We also describe the development of incretin-based pharmacotherapy, starting with exendin- 4 and ending with the identification of multi-incretin hormone receptor agonists, which appear to be the next major step in the fight against T2DM and obesity. We discuss the multi-agonists currently in clinical trials and how each new generation of these drugs improves their effectiveness. Since most glucose-dependent insulinotropic polypeptide (GIP) receptor: glucagon-like peptide- 1 receptor (GLP- 1) receptor: glucagon receptor triagonists compete in efficacy with bariatric surgery, the success of these agents in preclinical models and clinical trials suggests a bright future for multi-agonists in the treatment of metabolic diseases. To fully understand how these treatments affect body weight, further research is needed.