Assessing the Impact of Perceptions of Unpredictability on Objective Measures of Food Consumption and Metabolism

Background: Many people in the United States are overweight or obese. This natural history study will look into how life events during childhood can impact eating behaviors and weight gain as adults. Objective: To explore how childhood experiences affect adult eating behaviors. Eligibility: Healthy people aged 18 to 60 years. Design: Participants will have 3 clinic visits. They will be screened with blood tests. They will answer questions about their alcohol and tobacco use. At the next visit, participants will undergo these activities: Parts of their body (such as waist, neck, and thighs) will be measured with a tape. They will have an imaging scan to find out how much body fat they have. They will start wearing a device like a wristwatch that measures their physical activity. They will wear this device for up to 10 days. They will wear a device on their upper arm or belly that measures blood glucose (sugar) levels. Participants will wear this for 7-10 days. They will answer questions about their education, childhood, and routines. They will receive a kit to collect a stool sample at home. At the last visit, participants will have these tests: Participants will relax and breathe normally while wearing a clear, plastic canopy that fits over their entire head. Blood samples will be taken before and after participants drink a sugary drink. Participants will be offered a large selection of foods for lunch. They will eat as much as they want. Then they will answer questions about how they feel about food and themselves.

Study Description: The unpredictability schema - "a pervasive belief that other people cannot be trusted and future outcomes cannot be predicted or controlled" - has been hypothesized to (1) be shaped by parental/household dynamics and (2) impact appetitive and consumptive behaviors. However, studies on appetitive behaviors were mostly based on self-report and to our knowledge, no studies have examined objective measurements of energy intake or expenditure in association with unpredictability. Therefore, the current study seeks to examine whether the unpredictability schema as measured by a composite score of unpredictability assessments is associated with ad libitum food consumption and eating in the absence of hunger, measured objectively. Furthermore, we will examine the associations between the unpredictability schema and physical activity, resting metabolic rate/respiratory quotient, and glucose trajectories during an oral glucose tolerant test and continuous glucose monitoring in a cohort of healthy participants. Objectives: Primary Objective: * To determine whether an association exists between unpredictability schema measures (schema/beliefs and childhood experiences as measured by derived from the Child Unpredictability Index, Scale of Unpredictability Beliefs, Unpredictability Schema Scale, and Confusion, Hubbub, and Order Scale and, individually, by scale totals and subscales) and ad libitum food intake. * To determine whether an association exists between the unpredictability schema and experience scores and eating in the absence of hunger (as determined by the snack food taste test). Secondary Objectives: * To determine whether an association exists between measures of the unpredictability schema and experience scores and physical activity. * To determine whether an association exists between measures of the unpredictability schema and experience scores and resting metabolic rate and RQ. * To determine whether an association exists between measures of the unpredictability schema and experience scores and glucose values (CGM and OGTT). * To determine whether an association exists between measures of the unpredictability schema and experience scores and telomere length. * To determine whether an association exists between measures of the unpredictability schema and experience scores and with gut microbiota composition. Tertiary Objectives: * To determine the associations between measures of early childhood experiences (as measured by an overall composite measure derived by the maternal care/warmth subscale of the Parental Bonding Instrument and physical and emotional neglect subscales from the Childhood Trauma Questionnaire and, individually, by scale totals and subscales) and outcomes outlined in the primary and secondary objectives. * To determine whether an association exists between measures of early childhood experiences and the unpredictability schema and experience scores. * Examine psychosocial and physiological variables (based on theory and past literature) that may mediate or moderate the relationship between the unpredictability schema and our primary and secondary endpoints. * Examine associations of metabolic measures with psychosocial measures (e.g., perceived stress, anhedonia, anxiety, depression, etc.), hormonal endpoints, or future biomarker assayed at a later time point. Endpoints: Primary Endpoint: * Ad libitum Food Intake (kcal) measured from a buffet meal task. * Eating in the absence of hunger (kcal) from a snack food taste test. Secondary Endpoints: * Physical activity values and trajectories from the 10-day outpatient consumer wearable activity tracker assessment. * Resting metabolic rate and respiratory quotient values obtained from the metabolic hood. * Glucose values and trajectories from fasting labs, OGTT, and 10-day outpatient CGM assessment. * Telomere length (t/s ratio) * Gut Flora Composition Tertiary Endpoints: * Ad libitum Food Intake (kcal) measured from (1) a buffet meal task and (2) the snack food taste test; Physical activity values and trajectories from the 10-day outpatient consumer wearable activity tracker assessment; Resting metabolic rate and respiratory quotient values obtained from the metabolic hood; Glucose values and trajectories from fasting labs, OGTT, and 10-day outpatient CGM assessment. * Ad libitum Food Intake (kcal) measured from (1) a buffet meal task and (2) the snack food taste test; Physical activity values and trajectories from the 10-day outpatient consumer wearable activity tracker assessment; Resting metabolic rate and respiratory quotient values obtained from the metabolic hood; Glucose values and trajectories from fasting labs, OGTT, and 10-day outpatient CGM assessment. * Unpredictability schema and experience scores * Ad libitum Food Intake (kcal) measured from (1) a buffet meal task and (2) the snack food taste test; Physical activity values and trajectories from the 10-day outpatient consumer wearable activity tracker assessment; Resting metabolic rate and respiratory quotient values obtained from the metabolic hood; Glucose values and trajectories from fasting labs, OGTT, and 10-day outpatient CGM assessment. * Plasma hormone, metabolite and protein concentration measured following data collection.