Secular trends and determinants of energy intake measured in a research setting from 1999-2020.

Introduction: Historically, secular and seasonal trend analyses have been examined using self-report measures of intake. Rarely are objective measures and known determinants of dietary intake used in these analyses. Our objective was to quantify the seasonal and secular differences in an objective intake paradigm while considering the contribution of determinants, such as fat-free mass (FFM) index and spontaneous physical activity (SPA) limited to the restricted space of a whole-room calorimeter.

Acid accumulation is associated with metabolic alterations; higher energy, fat, and protein intake; and energy expenditure.

Objective: The objective of this study was to study how acid accumulation (lower plasma bicarbonate and higher anion gap [AG] and corrected anion gap [CAG]) correlates with metabolic parameters, food intake, and 24-h energy expenditure (EE).

Methods: Acid accumulation was measured in 286 healthy adults with estimated glomerular filtration rate > 60 mL/min/1.73 m.

Twenty-Four-Hour Urinary Sugars Biomarker in a Vending Machine Intake Paradigm in a Diverse Population.

Accurately measuring dietary sugars intake in large-scale epidemiological studies is necessary to understand dietary sugars' true impact on health. Researchers have developed a biomarker that can be used to assess total sugars intake. Our objective is to test this biomarker in diverse populations using an ad libitum intake protocol.

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) ( = 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.

Validation of Total Water Intake from the Automated Self-Administered 24-h Recall, 4-d Food Records, and a Food Frequency Questionnaire Using Doubly Labeled Water.

Background: Although prior evidence indicates that water intake is important for health, the ability to accurately measure community-dwelling intake is limited. Only a few studies have evaluated self-reported water intake against an objective recovery biomarker.

Objectives: The aim was to compare preformed water intakes (all sources including food) by multiple Automated Self-Administered 24-h recalls (ASA24s), food frequency questionnaires (FFQs), and 4-d food records (4DFRs) against a recovery biomarker, doubly labeled water (DLW), to assess measurement error.

Carbon Isotope Ratios of Plasma and RBC Fatty Acids Identify Meat Consumers in a 12-Week Inpatient Feeding Study of 32 Men.

Background: Molecular stable isotope ratios are a novel type of dietary biomarker with high sensitivity and specificity for certain foods. Among these, fatty acid carbon isotope ratios (CIRs) have strong potential but have not been investigated as dietary biomarkers.

Objectives: We evaluated whether fatty acid CIRs and mass proportions were associated with meat, fish, and sugar-sweetened beverage (SSB) intake.

Food insecurity is associated with higher respiratory quotient and lower glucagon-like peptide 1.

Objective: Food insecurity is known to be associated with obesity, but its association with physiological measures is unclear. Therefore, it was hypothesized that, compared with food-secure individuals, those with food insecurity would have higher 24-hour energy expenditure (EE [kilocalories per day]) and 24-hour respiratory quotient (RQ [ratio]). Subsequently, hormones involved in appetite regulation, substrate oxidation, and EE were explored.

Amino Acid Nitrogen Isotope Ratios Respond to Fish and Meat Intake in a 12-Week Inpatient Feeding Study of Men.

Background: The natural abundance nitrogen stable isotope ratio (NIR) of whole tissue correlates with animal protein intakes, including meat and fish. Amino acid (AA) NIRs (NIRAAs) are more variable than the whole-tissue NIRs and may thus better differentiate among foods.

Objectives: We evaluated whether NIRAAs were associated with intakes of fish and meat and whether these dietary associations were larger than with whole-tissue NIRs.

The counterbalancing effects of energy expenditure on body weight regulation: Orexigenic versus energy-consuming mechanisms.

Objective: Weight change is a dynamic function of whole-body energy balance resulting from the interplay between energy intake and energy expenditure (EE). Recent reports have provided evidence for the existence of a causal effect of EE on energy intake, suggesting that increased EE may drive overeating, thereby promoting future weight gain. This study investigated the relationships between ad libitum energy intake and 24-hour EE (24-h EE) in sedentary conditions versus long-term, free-living weight change using a mediation analysis framework.

Food insecurity moderates the relationship between momentary affect and adherence in a dietary intervention study.

Objective: Negative affect and food insecurity have been proposed to impede adherence to weight loss interventions. Therefore, this study examined the role of these variables on dietary adherence using Ecological Momentary Assessment.

Methods: A total of 50 participants (19 male participants; age = 49 [SD 14] years) participated in an outpatient dietary study.

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; 177 m; Age = 36 ± 11; BMI = 32 ± 8) were admitted to our clinical research unit.

Higher fasting plasma FGF21 concentration is associated with lower ad libitum soda consumption in humans.

Background: The hepatokine fibroblast growth factor 21 (FGF21) influences eating behavior and sugar consumption in rodent models. However, whether circulating FGF21 concentration is associated with food and soda intake in humans is still unclear.

Objective: We investigated whether fasting plasma FGF21 concentration is associated with objective measures of ad libitum food intake and soda consumption.

Metabolic Characterization of Meat, Fish, and Soda Intake in Males: Secondary Results from a Randomized Inpatient Pilot Study.

Objective: This study aimed to evaluate whether a 12-week, weight-maintaining, macronutrient-stable dietary intervention that varies only by meat, fish, or soda consumption alters 24-hour energy expenditure (24hrEE) and substrate oxidation.

Methods: Healthy males were recruited to participate in a 12-week inpatient study and were randomized to a weight-maintaining dietary intervention that contained varying combinations of meat (0% or 19%), fish (0% or 6%), or soda (0% or 14%) in a factorial design. Macronutrient composition across dietary intervention groups was as follows: 50% of energy from carbohydrates, 30% of energy from fat, and 20% of energy from protein.

Reduced Albumin Concentration Predicts Weight Gain and Higher Energy Intake in Humans.

Objective: Circulating albumin is negatively associated with adiposity but whether it is associated with increased energy intake, lower energy expenditure or weight gain has not been examined.

Methods: In (n=238; 146 men), we evaluated whether fasting albumin concentration was associated with 24-h energy expenditure and energy intake. In (n=325;167 men), we evaluated the association between plasma albumin and change in weight and body composition.

The carbon isotope ratios of nonessential amino acids identify sugar-sweetened beverage (SSB) consumers in a 12-wk inpatient feeding study of 32 men with varying SSB and meat exposures.

Background: The carbon isotope ratios (CIRs) of individual amino acids (AAs) may provide more sensitive and specific biomarkers of sugar-sweetened beverages (SSBs) than total tissue CIR. Because CIRs turn over slowly, long-term controlled-feeding studies are needed in their evaluation.

Objective: We assessed the responses of plasma and RBC CIRAA's to SSB and meat intake in a 12-wk inpatient feeding study.

Reduced metabolic efficiency in sedentary eucaloric conditions predicts greater weight regain in adults with obesity following sustained weight loss.

Background: Successful long-term weight loss maintenance after caloric restriction (CR) is rarely achieved. Besides known metabolic, behavioural, and cognitive factors, 24-hour energy expenditure (24hEE) relative to body size (i.e.

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 individuals and two groups of individuals with obesity.

Methods: In a 6-week outpatient dietary intervention (23 males; aged 48  [SD 14] years), lean participants (n = 23; BMI 23  [SD 2] kg/m ) received a weight-maintaining energy needs (WMEN) diet, and participants with obesity (BMI 36  [SD 7]) were randomized to either WMEN (n = 18) or a 35% calorie-reduced (CR) diet (n = 19).

Early adaptive thermogenesis is a determinant of weight loss after six weeks of caloric restriction in overweight subjects.

Background: Adaptive thermogenesis during prolonged energy deficit refers to the greater than expected reduction in energy expenditure (EE) independent of concomitant loss of metabolically active body mass.

Objective: As inter-individual variability in the magnitude of adaptive thermogenesis may influence the extent of energy deficit thereby predicting the amount of weight reduction, we investigated whether early adaptive thermogenesis is a determinant of weight loss after 6 weeks of daily 50% caloric restriction in an inpatient setting.

Design And Methods: The current study reports the results of an exploratory, secondary analysis in overweight but otherwise healthy subjects (n = 11, 7 men, 35 ± 9y, BMI = 40 ± 7 kg/m, body fat = 63.

Assessing established BMI variants for a role in nighttime eating behavior in robustly phenotyped Southwestern American Indians.

Background/objectives: Nighttime eating (NE) behavior has a genetic component and predicts weight gain. We hypothesized that some genetic variants, which affect NE would also show an effect on body mass index (BMI). We aimed to determine which known BMI variants associate with NE in Southwestern American Indians (SWAIs), who are at elevated risk for obesity.

Thigh Adipocyte Size is Inversely Related to Energy Intake and Respiratory Quotient in Healthy Women.

Objective: The relationship between adipocyte size and ad libitum energy intake has not been previously examined. This study hypothesized an inverse relationship between adipocyte size and daily energy intake (DEI).

Methods: Seventy healthy adults (39 men and 31 women; BMI 30.

Recharacterizing the Metabolic State of Energy Balance in Thrifty and Spendthrift Phenotypes.

Purpose: The human thrifty phenotype hypothesis presupposes that lower 24-hour (24h) energy expenditure (24EE) during famine preserves body mass and promotes survival. The prevailing view defines thrifty individuals as having a lower 24EE during fasting. However, it is also plausible that the greater decline in 24EE during fasting in thrifty individuals is due to higher 24EE during energy balance conditions (ENBAL).