Integrative neurocircuits that control metabolism and food intake.

Systemic metabolism has to be constantly adjusted to the variance of food intake and even be prepared for anticipated changes in nutrient availability. Therefore, the brain integrates multiple homeostatic signals with numerous cues that predict future deviations in energy supply. Recently, our understanding of the neural pathways underlying these regulatory principles-as well as their convergence in the hypothalamus as the key coordinator of food intake, energy expenditure, and glucose metabolism-have been revealed. These advances have changed our view of brain-dependent control of metabolic physiology. In this Review, we discuss new concepts about how alterations in these pathways contribute to the development of prevalent metabolic diseases such as obesity and type 2 diabetes mellitus and how this emerging knowledge may provide new targets for their treatment.

Differences in spinal posture and mobility between adults with obesity and normal weight individuals.

The aim of this study was to cross-sectionally investigate the relationships between obesity and spinal posture as well as mobility by comparing the spinal parameters between adults with obesity and normal-weight individuals. The spinal parameters were measured in 71 adults with obesity and 142 normal-weight individuals using a radiation-free back scan, the Idiag M360. Differences in spinal posture and movements between the two groups were determined using a two-way analysis of variance. Adults with obesity had greater thoracic kyphosis [difference between groups (Δ) = 6.1°, 95% CI 3.3°-8.9°, p < 0.0001] and thoracic lateral flexion (Δ = 14.5°, 95% CI 5.1°-23.8°, p = 0.002), as well as smaller thoracic flexion (Δ = 3.5°, 95% CI 0.2°-6.9°, p = 0.03), thoracic extension (Δ = 4.1°, 95% CI 1.1°-7.1°, p = 0.008), lumbar flexion (Δ = 10.4°, 95% CI 7.7°-13.5°, p < 0.0001), lumbar extension (Δ = 4.8°, 95% CI 2.2°-7.4°, p = 0.0003) and lumbar lateral flexion (Δ = 12.8°, 95% CI 9.8°-15.7°, p = < 0.0001) compared to those with normal weight. These findings provide relevant information about the characteristics of the spine in adults with obesity to be taken into careful consideration in the prescription of adapted physical activities within integrated multidisciplinary pathways of metabolic rehabilitation.

Association Between Markers of Adiposity During Childhood and Puberty Onset in Latino Girls.

CONTEXT: Prepubertal adiposity is associated with earlier puberty. It is unclear when this association starts, if all adiposity markers are similarly associated, and whether all pubertal milestones are similarly affected. OBJECTIVE: To evaluate the association between different adiposity markers during childhood and the timing of different pubertal milestones in Latino girls. DESIGN, SETTING, AND PARTICIPANTS: Longitudinal follow-up of 539 female participants of the Chilean Growth and Obesity Cohort recruited from childcare centers (mean age 3.5 years) from the southeast area of Santiago, Chile. Participants were singletons born between 2002 and 2003 within the normal birthweight range. Since 2006, a trained dietitian measured weight, height, waist circumference (WC) and skinfolds to estimate body mass index (BMI) Centers for Disease Control and Prevention percentiles, central obesity, percentage of fat mass (%FM), and fat mass index (FMI, fat mass/height2). MAIN OUTCOME: Since 2009, sexual maturation was assessed every 6 months to assess age at (1) thelarche, (2) pubarche, (3) menarche, and (4) peak height velocity (PHV). RESULTS: At thelarche, 12.5% were obese and 2% had central obesity. The median age of pubarche, menarche, and PHV were all associated with markers of adiposity at different time points during childhood whereas thelarche only with %FM and FMI. Adiposity clusters models showed that children with trajectories of high WC, %FM, and FMI during childhood were related with earlier thelarche, pubarche, menarche, and PHV but BMI trajectories only with menarche and PHV. CONCLUSIONS: Higher WC, %FM, and FMI were associated with earlier age at thelarche, pubarche, menarche, and PHV. The effect of BMI was less consistent.

Myopenic Obesity Determined by Fat Mass Percentage Predicts Risk of Aspirin-Induced Bleeding in Chinese Older Adults.

Background: Body mass index (BMI) correlates with aspirin-induced bleeding risk. However, skeletal muscle mass (SMM) loss and fat gain commonly occur with aging, making BMI not a reasonable marker of bleeding risk in older individuals. In the present study, we aimed to investigate the prognostic value of myopenic obesity based on the percent of fat mass (%FM) for aspirin-induced bleeding in Chinese patients over 60 years old. Methods: We prospectively analyzed 185 patients taking aspirin for primary and secondary prevention of cardiovascular diseases. Body composition parameters were estimated using bioelectrical impedance analysis. We defined myopenic obesity (MO) as a height-adjusted appendicular SMM <7.0 kg/m2 in males and <5.7 kg/m2 in females with a %FM >29% in males and >41% in females or a BMI ≥25 kg/m2. The patients were categorized into four groups by the presence or absence of myopenia and obesity. Results: Based on the %FM grouping, the bleeding risk was significantly higher in the MO group, followed by the nonmyopenic obesity, myopenic nonobesity, and nonmyopenic nonobesity groups (P = 0.044). No statistically significant differences in the probability of bleeding events were observed among the four BMI-based groups (P = 0.502). Multivariate Cox analysis indicated that MO (hazard ratio [HR] 2.724, 95% confidence interval [CI] 1.073-6.918, P = 0.035), aspirin dose (100 vs 50 mg/day, HR 2.609, 95% CI 1.291-5.273, P = 0.008), concomitant use of histamine-2 receptor antagonists and proton pump inhibitors (HR 1.777, 95% CI 1.007-3.137, P = 0.047), and hemorrhage history (HR 2.576, 95% CI 1.355-4.897, P = 0.004) were associated with bleeding events independently. Conclusion: %FM-based MO was an independent predictor of aspirin-induced bleeding in older Chinese individuals. Reducing %FM rather than BMI should be an optimal strategy for the management of myopenic obesity.

Weight status change from birth to childhood and the odds of high blood pressure among Chinese children.

Background: It is well documented that birth weight and childhood weight are associated with the blood pressure (BP) levels in childhood. However, the impact of weight status change from birth to childhood on BP among children is less well described. We aimed to assess the association between changes in weight status from birth to childhood and high BP in childhood. Methods and results: Data were obtained from a cross-sectional survey conducted in Jinan, China, and a total of 5,546 children aged 6-17 years were included in this study. Based on the birth weight status [high weight (> 4,000 g) vs. normal weight (2,500-4,000 g)] and childhood weight status during the survey period [high weight (overweight and obesity) vs. normal weight], children were assigned into four groups: persistently normal weight (normal birth weight and normal childhood weight), resolved high weight (high birth weight but normal childhood weight), incident high weight (normal birth weight but high childhood weight), and persistently high weight (high birth weight and high childhood weight). After adjustment for sex and age, BP in childhood was more responsive to current body mass index (BMI) than birth weight. After adjustment for the potential covariates, compared with children who had persistently normal weight from birth to childhood, those with incident high weight (odds ratio [OR] = 3.88, 95% confidence interval [CI] = 3.29-4.57) and persistently high weight (OR = 3.52, 95% CI = 2.71-4.57) were associated with the increased odds of childhood high BP. However, children who had resolved high weight did not have significantly increased odds of high BP in childhood (OR = 0.86, 95% CI = 0.59-1.25). Conclusion: The association of BP with recent BMI was stronger than with birth weight. Children who had incident or persistently high weight from birth to childhood had increased odds of high BP in childhood, whereas the odds was not significantly increased among those with high birth weight but changed to normal weight in childhood. Our findings highlight the importance of maintaining an appropriate weight in the early lifetime for the prevention of high BP and other related diseases, especially for those with high birth weight.

How does obesity affect mortality through blood pressure and blood glucose in Chinese and US citizens? Insights from a causal mediation analysis of two large cohorts.

Background: Obesity, which has reached the scale of a global pandemic, is a leading cause of premature death. It is unclear to what extent its effect on mortality was driven by blood pressure or glucose levels in people of different ethnicities. Methods: We conducted a causal mediation analysis to estimate the mediation effect of blood pressure and glucose between body mass index (BMI) or waist-hip ratio (WHR) on mortality based on data from the China Kadoorie Biobank (CKB) (n = 458 385) and US National Health and Nutrition Examination Survey (NHANES) (1999-2008, n = 20 726). Results: The WHR's effect on mortality was mediated by blood pressure and glucose in the CKB data set by 38.7% (95% confidence interval (CI) = 34.1, 43.2) and 36.4% (95% CI = 31.6, 42.8), whereas in NHANES by 6.0% (95% CI = 2.3, 8.3) and 11.2% (95% CI = 4.7, 22.7), respectively. For associations between BMI and mortality in subjects with overweight or obesity, the mediator proportion of blood glucose and pressure was 49.4% (95% CI = 40.1, 62.5) and 16.9% (95% CI = 13.6, 22.9) in CKB and 9.10% (95% CI = 2.2, 25.9) and 16.7% (95% CI = 7.3, 49.0) in NHANES, respectively. We stratified the patients by their blood glucose, blood pressure level, or both into four groups. The effect of WHR on mortality was comparable across subgroups in either cohort. The associations between BMI and mortality were stronger in patients with higher blood pressure in CKB (P = 0.011) and blood glucose in NHANES (P = 0.035) in patients with overweight and obesity. Conclusions: The relationship between WHR and mortality in the CKB data set was potentially caused by blood pressure and glucose to a much greater extent than in the NHANES one. The effect of BMI influenced by blood pressure was significantly higher among Chinese individuals with overweight and obesity. These results implicate a different intervention strategy is required for blood pressure and blood glucose in China and US to prevent obesity and obesity-related premature death.

Defining and diagnosing sarcopenia: Is the glass now half full?

Low muscle mass and function exert a substantial negative impact on quality of life, health and ultimately survival, but their definition, identification and combination to define sarcopenia have suffered from lack of universal consensus. Methodological issues have also contributed to incomplete agreement, as different approaches, techniques and potential surrogate measures inevitably lead to partly different conclusions. As a consequence: 1) awareness of sarcopenia and implementation of diagnostic procedures in clinical practice have been limited; 2) patient identification and evaluation of therapeutic strategies is largely incomplete. Significant progress has however recently occurred after major diagnostic algorithms have been developed, with common features and promising perspectives for growing consensus. At the same time, the need for further refinement of the sarcopenia concept has emerged, to address its increasingly recognized clinical heterogeneity. This includes potential differential underlying mechanisms and clinical features for age- and disease-driven sarcopenia, and the emerging challenge of sarcopenia in persons with obesity. Here, we will review existing algorithms to diagnose sarcopenia, and major open methodological issues to assess skeletal muscle mass and function under different clinical conditions, in order to highlight similarities and differences. Potential for consensus on sarcopenia diagnosis as well as emerging new challenges will be discussed.

Obesidad: alternativas al paradigma pesocéntrico y patologizante. Primera entrega / Obesity: alternatives to the weight-centric and pathologizing paradigm. First part

Si bien para los médicos la obesidad es una palabra técnica, para muchas personas tiene la implicaría de un largo sufrimiento en relación a su cuerpo. Históricamente, la medicina tradicional se ha comportado como una barrera en la atención a las personas con exceso de peso debido a la gordofobia y a una perspectiva reduccionista pesocentrista. Es preocupante que las ciencias y prácticas de la salud aún tengan esta mirada sobre la gordura, ya que supone un sesgo que impide que las personas sean atendidas integralmente, vulnerando sus derechos en nombre de una preocupación médica y anteponiendo el descenso de peso frente a otras necesidades de los pacientes. Este artículo, si bien intenta modestamente abrir una reflexión filosófica sobre el cuerpo, la medicina hegemónica y la enfermedad, también tiene como objetivo brindar herramientas técnicas y no técnicas para abordar la obesidad desde otro lugar. En esta primera entrega, desarrollaremos el abordaje integral de la persona con cuerpo gordo. La segunda entrega estará enfocada en los tratamientos farmacológicos, no farmacológicos y quirúrgicos de la obesidad. (AI)

Although obesity is a technical word for doctors, it implies long-term suffering in relation to their bodies for many people. Historically, traditional medicine has behaved as a barrier in caring for people with excess weight due to fatphobia and aweight-centric reductionist perspective. It is worrying that health sciences and practices still have this view of fatness, sinceit implies a bias that prevents people from being thoroughly cared for, violating their rights in the name of medical concernand putting weight loss before other patients' needs. This article modestly attempts to open a philosophical reflection about the body, hegemonic medicine, and disease, while also aiming to provide technical and non-technical tools to approach obesity. In this first part, we will explain the comprehensive approach to the person with a fat body. The second part will focus on pharmacological, non-pharmacological, and surgical treatments for obesity. (AU)

Increased Meal Size but Reduced Meal-Stimulated Plasma Cholecystokinin Concentrations in Women With Obesity.

To better understand the physiological basis of obesity in women, we investigated whether obesity or menstrual cycle phase affects laboratory test-meal size or meal-stimulated plasma cholecystokinin (CCK) concentration. Women with healthy weight (body mass index [BMI] of 18.5-24.9 kg/m2, N = 16) or obesity (BMI 30-39.9 kg/m2, N = 20) were tested once in the late-follicular or peri-ovulatory phase (LF/PO) and once in the mid-luteal phase (ML). Meals of ham sandwiches were offered and blood was sampled. Menstrual cycle phases were verified with participants' reports of menses and measurements of progesterone and luteinizing hormone (LH) concentrations. Women with obesity ate significantly larger meals than women with healthy weight, (mean, 711 [95% CI, 402-1013] kJ, P = 0.001, during the LF/PO and 426 [105-734] kJ, P = 0.027, larger during the ML). Women with healthy weight ate smaller meals during LF/PO than ML (decrease, 510 [192-821 kJ], P = 0.008), but women with obesity did not (decrease, 226 [-87-542] kJ, P = 0.15). CCK concentrations 18 to 30 minutes after meal onset were lower in women with obesity than in women with healthy weight during LF/PO (3.6 [3.1-4.1] vs 6.1 [4.5-7.7] pmol/L; P = 0.004), but not during ML, with a significant interaction effect (1.8 [1.2-2.4] pmol/L, P = 0.048). Women with obesity consumed larger meals than women with healthy weight but displayed reduced meal-stimulated plasma CCK concentrations. These data are consistent with the hypothesis that a defect in CCK secretion compromises satiation in obese women and contributes to the development or maintenance of obesity.

The History of Obesity Research.

Perhaps the most unexpected development in pediatric endocrinology in the past 50 years has been the recognition of obesity as an endocrine/metabolic disorder rather than a life choice or moral failing. The history of obesity research is disjointed, having followed two separate paths in the 20th century, based on two independent yet overlapping paradigms. Proponents of the "Energy Storage" hypothesis point to data implicating monogenetic disorders, the ventromedial hypothalamus, insulin, cortisol, and the adipocyte itself in the pathogenesis of obesity. Alternatively, proponents of the "Energy Balance" hypothesis point to data implicating increased caloric intake, decreased caloric expenditure, gastrointestinal hormones, and microbiome changes as being critical for obesity. These two separate lines of research merged somewhat with the discovery of leptin in 1994, as leptin established a major hormonal role in weight control. Leptin has explained some of the dichotomy and has proved essential in understanding the importance of developmental programming and epigenetics. However, the mystery of leptin resistance remains unsolved. Despite all our collective knowledge, we appear no closer in solving the obesity puzzle today than we were 50 years ago.

Review and evaluation of vancomycin dosing guidelines for obese individuals.

INTRODUCTION: Vancomycin dosing decisions are informed by factors such as body weight and renal function. It is important to understand the impact of obesity on vancomycin pharmacokinetics and how this may influence dosing decisions. Vancomycin dosing guidelines use varied descriptors of body weight and renal function. There is uncertainty whether current dosing guidelines result in attainment of therapeutic targets in obese individuals. AREAS COVERED: Literature was explored using PubMed, Embase, and Google Scholar for articles from January 1980 to July 2021 regarding obesity-driven physiological changes, their influence on vancomycin pharmacokinetics and body size descriptors and renal function calculations in vancomycin dosing. Pharmacokinetic simulations reflective of international vancomycin dosing guidelines were conducted to evaluate the ability of using total, ideal, and adjusted body weight, as well as Cockcroft-Gault and CKD-EPI equations to attain an area-under-the-curve to minimum inhibitory concentration ratio (AUC24/MIC) target (400-650) in obese individuals. EXPERT OPINION: Vancomycin pharmacokinetics in obese individuals remains debated. Guidelines that determine loading doses using total body weight, and maintenance doses adjusted based on renal function and adjusted body weight, may be most appropriate for obese individuals. Use of ideal body weight leads to subtherapeutic vancomycin exposure and underestimation of renal function.

Sex differences in the ventilatory responses to exercise in mild to moderate obesity.

NEW FINDINGS: What is the central question of the study? What are the sex differences in ventilatory responses during exercise in adults with obesity? What is the main finding and its importance? Tidal volume and expiratory flows are lower in females when compared with males at higher levels of ventilation despite small increases in end-expiratory lung volumes. Since dyspnoea on exertion is a frequent complaint, particularly in females with obesity, careful attention should be paid to unpleasant respiratory symptoms and mechanical ventilatory constraints while prescribing exercise. ABSTRACT: Obesity is associated with altered ventilatory responses, which may be exacerbated in females due to the functional consequences of sex-related morphological differences in the respiratory system. This study examined sex differences in ventilatory responses during exercise in adults with obesity. Healthy adults with obesity (n = 73; 48 females) underwent pulmonary function testing, underwater weighing, magnetic resonance imaging (MRI), a graded exercise test to exhaustion, and two constant work rate exercise tests; one at a fixed work rate (60 W for females and 105 W for males) and one at a relative intensity (50% of peak oxygen uptake, V ̇ O 2 peak ${\dot{V}}_{{{\rm{O}}}_{\rm{2}}{\rm{peak}}}$ ). Metabolic, respiratory and perceptual responses were assessed during exercise. Compared with males, females used a smaller proportion of their ventilatory capacity at peak exercise (69.13 ± 14.49 vs. 77.41 ± 17.06% maximum voluntary ventilation, P = 0.0374). Females also utilized a smaller proportion of their forced vital capacity (FVC) at peak exercise (tidal volume: 48.51 ± 9.29 vs. 54.12 ± 10.43%FVC, P = 0.0218). End-expiratory lung volumes were 2-4% higher in females compared with males during exercise (P < 0.05), while end-inspiratory lung volumes were similar. Since the males were initiating inspiration from a lower lung volume, they experienced greater expiratory flow limitation during exercise. Ratings of perceived breathlessness during exercise were similar between females and males at comparable levels of ventilation. In summary, sex differences in the manifestations of obesity-related mechanical ventilatory constraints were observed. Since dyspnoea on exertion is a common complaint in patients with obesity, particularly in females, exercise prescriptions should be tailored with the goal of minimizing unpleasant respiratory sensations.

Obesidade genética não sindrômica: histórico, fisiopatologia e principais genes / Non-syndromic genetic obesity: history, pathophysiology and key genes

A obesidade é definida pelo excesso de gordura corporal acumulada no tecido adiposo quando o indivíduo atinge valores de IMC igual ou superior a 30 Kg/m2. Constitui um dos principais fatores de risco para várias doenças não transmissíveis (DNTs) como por exemplo, diabetes mellitus tipo 2 (DM2), doenças cardiovasculares, hipertensão arterial, acidente vascular cerebral e até mesmo o câncer. Embora a obesidade esteja diretamente relacionada com o consumo calórico excessivo em relação ao gasto energético diário, sua etiologia pode estar associada aos baixos níveis de atividade física, às alterações neuroendócrinas e aos fatores genéticos. Considerando o componente genético, esta pode ser classificada como sindrômicas e estar associada às alterações cromossômicas estruturais ou numéricas, ou como não sindrômica, quando relacionada, principalmente, com os polimorfismos de nucleotídeos simples (SNPs) em alelos que atuam como herança monogênica, ou ainda com a interação vários genes (poligênica multifatorial). Apesar de existirem muitas etiologias diferentes, normalmente a obesidade é tratada a partir da mesma abordagem, desconsiderando a fisiologia que a desencadeou. Dessa forma, o objetivo do presente trabalho foi abordar a obesidade genética não sindrômica por meio a) da descrição breve de perspectiva histórica sobre seu entendimento; b) da exposição dos principais mecanismos moleculares envolvidos com o controle de peso; c) da compilação dos principais genes e SNPs relacionados; d) da definição dos principais genes; e e) da abordagem das principais perspectivas de intervenção.

Obesity is defined as excess body fat accumulated in the adipose tissue when the individual reaches BMI values equal to or greater than 30 kg/m2. It is one of the main risk factors for several non-communicable diseases (NCDs), such as Type 2 Diabetes mellitus (T2D), cardiovascular diseases, high blood pressure, stroke and even cancer. Although obesity is directly related to excessive calorie intake in relation to daily energy expenditure, its etiology may be associated with low levels of physical activity, neuroendocrine changes, and genetic factors. Considering the genetic component, it can be classified as syndromic and be associated with chromosomal or numerical changes, or as non-syndromic and being related mainly to single nucleotide polymorphisms (SNPs) in alleles that act as monogenic inheritance, or with an interaction of several genes (multifactorial polygenic). Although there are many different etiologies, obesity is usually treated using the same approach, disregarding the physiology that triggered it. Thus, the aim of this study was to address non-syndromic genetic obesity through a) a brief description of a historical perspective on its understanding; b) the exposure of the main molecular mechanisms involved in weight control, c) the compilation of the key genes and related SNPs, d) the definition of the key genes and e) the approach of the main intervention representations.

Exceso de grasa visceral asociado a severidad de COVID-19, cuantificado por bioimpedancia / Excess visceral fat associated with severity of COVID-19 quantified by bioimpedance

Hay dos tipos principales de tejido adiposo; el subcutáneo, que es menos activo metabólicamente, y el tejido adiposo visceral, que secreta constantemente citocinas inflamatorias y está relacionado a enfermedades metabólicas y cardiovasculares. Nuestro objetivo fue identificar la asociación entre el exceso de grasa visceral y la severidad de enfermedad en pacientes con COVID-19. Se realizó un estudio observacional analítico que incluyó a pacientes con COVID-19 admitidos al Hospital Carrión de Huancayo, Perú. Se utilizó la balanza de bioimpedancia para cuantificar la composición corporal, la variable dependiente fue la severidad de enfermedad. Se utilizó el análisis de regresión logística para determinar la asociación de la grasa visceral y otros parámetros antropométricos con severidad de enfermedad. Se analizaron a 120 personas con COVID-19, la edad promedio fue 50 años, el sexo masculino fue 60%. De acuerdo a los valores de la composición corporal emitidos por el equipo de bioimpedancia: La grasa visceral > 15Kg (OR 7,31; p = 0,001); la grasa corporal total > 35% (OR 5,58; p = 0,009) y el exceso de peso > 20Kg (OR 6,96; p = 0,011) fueron los parámetros asociados a enfermedad severa por COVID-19. La relación positiva entre el perímetro abdominal y la cantidad de grasa visceral fue significativo (p = 0,01). En la composición corporal, el exceso de grasa visceral es el mayor parámetro asociado a enfermedad severa por COVID-19(AU)

There are two main types of adipose tissue; the subcutaneous, which is less metabolically active, and the visceral adipose tissue, which constantly secretes inflammatory cytokines and is related to metabolic and cardiovascular diseases. Our objetive was to identify the association between the excess of visceral fat and disease severity in COVID-19 patients. An analytical observational study was carried out which included patients with COVID-19 admitted to the Carrión Hospital in Huancayo, Peru. The bioimpedance balance was used to quantify the body composition; the dependent variable was the severity of the disease. A logistic regression analysis was used to determine the association of visceral fat and other anthropometric parameters with the severity of the disease. Out of 120 people with COVID-19 were analyzed, the average age was 50 years, the male sex was 60%. According to the body composition values issued by the bioimpedance team: Visceral fat> 15Kg (OR 7.31; p = 0.001); Total body fat> 35% (OR 5.58; p = 0.009) and excess weight> 20Kg (OR 6.96; p = 0.011) were the parameters associated with severe disease due to COVID-19. The positive relationship between abdominal circumference and the amount of visceral fat was significant (p = 0.01). In body composition, excess visceral fat is the main parameter associated with severe COVID-19 disease(AU)

Masticatory function according to body mass index: part I: kinematic analysis using different food textures / Función masticatoria según índice de masa corporal: parte I: análisis cinemático utilizando diferentes texturas de alimentos

Introduction: Chewing is a learned orofacial function, important in the nutrition process of most mammals. It has been described that it can vary according to the characteristics of the individuals and the characteristics of the food. The aim of this study was to compare the kinematic characteristics of mastication in subjects with different body mass index (BMI), including foods of different hardness in the analysis. Material and Methods: A cross-sectional observational study was conducted. The mastication of 3.7 g of peanut (soft food) and 3.7 g of carrot (hard food) was compared among three study groups formed according to BMI: normal weight (BMI 18.5-24.9), overweight (BMI 25-29.9) and obese (BMI ≥30); each with 7 participants. The kinematics of the masticatory movement were assessed with a 3D Electromagnetic Articulograph, the characteristics analyzed were number of masticatory cycles, masticatory frequency, speed and area of the cycles. Results: No significant differences were noted among the study groups for the number of masticatory cycles, frequency or speed in the two foods studied. It was observed that when chewing carrot, the horizontal area of the masticatory cycles was significantly larger in the obese than in the overweight group. However, when chewing peanuts, this parameter did not present significant differences among the different groups. A comparison of the characteristics of mastication of the two foods revealed that the carrot chewing presented a significantly greater masticatory frequency and speed than the peanut chewing. Conclusion: This study demonstrated that food hardness influences the kinematic characteristics of mastication more than BMI, noting that hard foods are masticated faster and more frequently than soft foods and that masticatory frequency tends to increase with BMI.

Introduction: Chewing is a learned orofacial function, important in the nutrition process of most mammals. It has been described that it can vary according to the characteristics of the individuals and the characteristics of the food. The aim of this study was to compare the kinematic cha-racteristics of mastication in subjects with different body mass index (BMI), including foods of different hardness in the analysis. Material and Methods: A cross-sectional observational study was con- ducted. The mastication of 3.7 g of peanut (soft food) and 3.7 g of carrot (hard food) was compared among three study groups formed according to BMI: normal weight (BMI 18.5-24.9), overweight (BMI 25-29.9) and obese (BMI ?30); each with 7 participants. The kinematics of the masticatory movement were assessed with a 3D Electromagnetic Articulograph, the characteristics analyzed were number of masticatory cycles, masticatory frequency, speed and area of the cycles. Results: No significant differences were noted among the study groups for the number of masticatory cycles, frequency or speed in the two foods studied. It was observed that when chewing carrot, the horizontal area of the masticatory cycles was significantly larger in the obese than in the overweight group. However, when chewing peanuts, this parameter did not present significant differences among the different groups. A comparison of the characteristics of mastication of the two foods revealed that the carrot chewing presented a significantly greater masticatory frequency and speed than the peanut chewing. Conclusion: This study demonstrated that food hardness influences the kinematic characteristics of mastication more than BMI, noting that hard foods are masticated faster and more frequently than soft foods and that masticatory frequency tends to increase with BMI.