Disinhibition augments thirst perception from two dehydrating stimuli in men

Physiological systems controlling water and energy ingestion are coordinated. Whether maladaptive eating behavior and appetite for water are linked is unknown. Thus, we sought to investigate the association between maladaptive eating and both thirst and water drinking behavior with two dehydrating conditions. Twenty-two lean men and 20 men with obesity (mean age 32.3 ± 8.4 years and 30.0 ± 11.1 years, respectively) completed the Three-Factor Eating Questionnaire (TFEQ) and Gormally Binge Eating Scale. On separate days, volunteers were dehydrated by a 2-h hypertonic saline infusion and a 24-h water deprivation, and thirst was measured on a 100-mm visual analogue scale (VAS) during each procedure. After each dehydrating condition, ad libitum water intake was measured. In the saline infusion, higher Disinhibition on the TFEQ was associated with thirst in the lean group (β = 4.2 mm VAS, p = 0.03) but not in the group with obesity (p = 0.51). In the water-deprivation condition, higher Disinhibition was also associated with thirst in the lean group (β = 5.6 mm VAS, p = 0.01) with the strength of relationship being 3.5-fold stronger than that observed in the group with obesity (β = 1.6 mm VAS, p = 0.0003). Hunger, Restraint, and binge-eating scores were not associated with thirst in either dehydrating condition (all p > 0.05). Maladaptive eating behaviors were not associated with ad libitum water intake (all p > 0.05). Disinhibition is associated with higher thirst perception in healthy weight individuals and may be attenuated in obesity. The characteristics of disinhibition which typically includes a heightened readiness to eat, may reflect a more general phenotype that also reflects a readiness to drink

Meal-to-meal and day-to-day macronutrient variation in an ad libitum vending food paradigm

Background Theory posits that macronutrient intake is regulated by protein consumption and adequate intake of protein results in consumption of less carbohydrates and fat. The current study investigates the effect of protein intake on calorie and macronutrient content using an ad libitum vending machine paradigm. Methods Healthy volunteers (n = 287; 177m; Age = 36 ± 11; BMI = 32 ± 8) were admitted to our clinical research unit. Macronutrient meal content (grams) and energy intake (Kcal) were quantified by specialized food processing software and collected on an hourly basis over a three-day period using a validated ad libitum vending machine paradigm. Body composition was assessed by DXA. Lagged multi-level models accounting for age, sex, race/ethnicity, fat and fat free mass indices were fitted to examine the impact of prior macronutrient content on subsequent meals. Results Protein intake was associated with decreased energy intake (Kcal; B = −1.67 kcal, p = 0.0048), lower protein and carbohydrate intake (B = −0.08 grams, p = 0.0006; B = −0.21 grams, p = 0.0003, respectively) at subsequent meals. Daily Macronutrient intake and subsequent intake were positively associated. Conclusions Dietary protein exhibits a negative regulatory effect on a short-term meal-to-meal rather than day-to-day basis. In the setting of readily available food, protein intake impacts energy intake only over very short time courses

Cognitive dietary restraint, disinhibition, and hunger are associated with 24-h energy expenditure

Background Higher energy expenditure (EE) is associated with greater food intake, possibly because the human body senses EE and modifies eating behaviors to regulate food intake and ultimately achieve energy balance. As eating behaviors are also influenced by social and cultural factors, any association between EE and eating behavior may differ between ethnicities and sexes. Objective To assess relationships between EE and eating behavior constructs of the Three-Factor Eating Questionnaire (TFEQ). Subjects/Methods In all, 307 healthy adults (201 M/106 F, 160 Native Americans) completed the TFEQ and had measures of 24-h EE in a whole-room calorimeter during energy balance. Body composition was assessed by DXA. Results On average, adjusted 24-h EE was lower (β = −229 kcal/day, CI: −309 to −148, p < 0.001) but cognitive restraint (Δ = + 1.5; CI: 0.5 to 2.5, p = 0.003) and disinhibition (Δ = + 2.1, CI: 1.3 to 2.8, p < 0.001) scores were higher in women compared with men. In Native Americans, adjusted 24-h EE (β = + 94 kcal/day, CI: 48 to 139, p < 0.001) and disinhibition scores (Δ = + 1.0, CI: 0.1 to 2.0, p = 0.003) were higher compared with other ethnicities. Higher 24-h EE associated with lower cognitive restraint in women (ρ = −0.20, p = 0.04), but not men (p = 0.71; interaction term p = 0.01) with no ethnic differences. Greater 24-h EE associated with higher disinhibition (ρ = 0.20, p = 0.001) and hunger cues (ρ = 0.16, p = 0.004) with no gender differences. These associations were primarily present in non-Native Americans (ρ = 0.23, p = 0.006 and ρ = 0.25, p = 0.003) but not observed in Native Americans (both p > 0.40). Conclusions Higher EE is associated with psychological constructs of eating behaviors that favors overeating including lower cognitive restraint, higher dietary disinhibition, and greater susceptibility to hungers cues, supporting the existence of energy-sensing mechanisms influencing human eating behavior. These associations were observed in ethnicities other than Native Americans, possibly explaining the contradictory relationships reported between EE and weight change in different ethnic groups. We propose that increased EE may alter eating behaviors, potentially leading to uncontrolled overeating and weight gain

Trends in spontaneous physical activity and energy expenditure among adults in a respiratory chamber, 1985 to 2005

Objective Fidgeting, a type of spontaneous physical activity (SPA), has substantial thermogenic potential. This research aims to examine secular trends in SPA and energy expenditure (EE) inside a respiratory chamber. Methods From 1985 to 2005, healthy adults (n = 678; mean age: 28.8 years; men: 60%; 522 Indigenous American, 129 White, and 27 Black) had a 24-hour stay in the respiratory chamber equipped with radar sensors. Body composition, glucose tolerance, fasting insulin, insulin action (hyperinsulinemic-euglycemic clamp), and insulin secretion (intravenous glucose tolerance test) were measured as covariates. Results SPA, adjusted for age, sex, race, and body composition, declined (r = −0.30, p < 0.0001), with a concomitant rise in the energy cost of SPA (r = 0.30, p < 0.0001). The 24-hour EE adjusted for covariates increased (r = 0.31, p < 0.0001), which was reflected in increases in EE during sleep (r = 0.18, p < 0.0001) and during the awake, fed condition (r = 0.28, p < 0.0001). The secular trends in SPA or 24-hour EE were unchanged with adjustment for measures related to glucose metabolism. Conclusions Secular trend analyses showed a decline in fidgeting. However, this decline in SPA was partially counterbalanced by an increase in energy cost of this activity and a rise in EE. Nevertheless, our results support public health efforts to promote small but sustained changes in these behaviors

Is Dietary Non-Adherence unique to obesity and weight loss? Results from a randomized clinical trial

Objective: Weight stigma is associated with poor dietary adherence, yet adherence is essential for weight loss and maintenance. This study aimed to determine differences in dietary adherence and perceived hunger between lean and two groups of individuals with obesity. Methods: In a 6-week outpatient dietary intervention (23males; age 48±14), lean participants (n=23; BMI 23±2 kg/m2 ) received a weight maintaining diet (WMEN) and participants with obesity (BMI 36±7) were randomized to either WMEN (n=18) or 35% calorie reduced (CR) diet (n=19). All food was provided and multiple All food was provided and multiple adherence and hunger ratings were assessed daily and weekly on an outpatient basis and in person at twice weekly visits (e.g. 24h recall, diaries, etc.). Results: Weight decreased more in individuals with obesity CR group (β=-0.301kg/week, p=0.02) compared to lean and individuals with obesity WMEN groups. However, total percent adherence did not differ between groups (p=0.60) and hunger scores did not change across groups over time (p=0.08). Conclusions: Results indicate there are no differences in dietary adherence between lean and individuals with obesity and adherence is not associated with adiposity or hunger. Thus, the belief that non-adherence (e.g. lack of willpower) is unique to obesity is untrue and may perpetuate weight bias and stigma

Water intake, thirst, and copeptin responses to two dehydrating stimuli in lean men and men with obesity

Objective Physiological systems responsible for water homeostasis and energy metabolism are interconnected. This study hypothesized altered responses to dehydration including thirst, ad libitum water intake, and copeptin in men with obesity. Methods Forty-two men (22 lean and 20 with obesity) were stimulated by a 2-hour hypertonic saline infusion and a 24-hour water deprivation. In each dehydrating condition, thirst, ad libitum water intake after dehydration, and urinary and hormonal responses including copeptin were assessed. Results After each dehydration condition, ad libitum water intake was similar between both groups (p > 0.05); however, those with obesity reported feeling less thirsty (p < 0.05) and had decreased copeptin response and higher urinary sodium concentrations when stressed (p < 0.05). Angiotensin II, aldosterone, atrial and brain natriuretic peptides, and apelin concentrations did not differ by adiposity group and did not explain the different thirst or copeptin responses in men with obesity. However, leptin was associated with copeptin response in lean individuals during the hypertonic saline infusion (p < 0.05), but the relationship was diminished in those with obesity. Conclusions Diminished thirst and copeptin responses are part of the obesity phenotype and may be influenced by leptin. Adiposity may impact pathways regulating thirst and vasopressin release, warranting further investigation

Is Dietary Nonadherence Unique to Obesity and Weight Loss? Results From a Randomized Clinical Trial

Objective: Weight stigma is associated with poor dietary adherence, yet adherence is essential for weight loss and maintenance. This study aimed to determine differences in dietary adherence and perceived hunger between lean and two groups of individuals with obesity. Methods: In a 6-week outpatient dietary intervention (23males; age 48±14), lean participants (n=23; BMI 23±2 kg/m2 ) received a weight maintaining diet (WMEN) and participants with obesity (BMI 36±7) were randomized to either WMEN (n=18) or 35% calorie reduced (CR) diet (n=19). All food was provided and multiple All food was provided and multiple adherence and hunger ratings were assessed daily and weekly on an outpatient basis and in person at twice weekly visits (e.g. 24h recall, diaries, etc.). Results: Weight decreased more in individuals with obesity CR group (β=-0.301kg/week, p=0.02) compared to lean and individuals with obesity WMEN groups. However, total percent adherence did not differ between groups (p=0.60) and hunger scores did not change across groups over time (p=0.08). Conclusions: Results indicate there are no differences in dietary adherence between lean and individuals with obesity and adherence is not associated with adiposity or hunger. Thus, the belief that non-adherence (e.g. lack of willpower) is unique to obesity is untrue and may perpetuate weight bias and stigma

Dietary Adherence Is Associated with Perceived Stress, Anhedonia, and Food Insecurity Independent of Adiposity

We examined whether perceived stress, anhedonia, and food insecurity were associated with dietary adherence during a 6-week intervention. Sixty participants (23 m; 53 ± 14 y) completed psychosocial measures and were provided with full meals. Individuals with obesity were randomized to a weight-maintaining energy needs (WMENs) (n = 18; BMI 33 ± 4) or a 35% calorie-reduced diet (n = 19; BMI 38 ± 9); normal-weight individuals (n = 23; BMI 23 ± 2) were assigned to a WMENs diet. Adherence scores were determined via weekly assessments and daily ecological momentary assessments (EMAs) of real-time behavior in a natural environment. Perceived stress and anhedonia were associated with % body fat (all r-values > 0.25, all p-values r = −0.31, p = 0.02), anhedonia (r = −0.34, p = 0.01), and food insecurity (r = −0.27, p = 0.04) were associated with lower adherence scores, even after adjusting for age, sex, and % body fat. In all adjusted models, % body fat was not associated with adherence. Higher measures of stress, anhedonia, and food insecurity predicted lower adherence independently of body fat, indicating that psychosocial factors are important targets for successful adherence to dietary interventions, regardless of body size