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.

* INCLUSION CRITERIA: In order to be eligible to participate in this study, an individual must meet all of the following criteria: * Stated willingness to comply with all study procedures and availability for the duration of the study. * 18-60 years of age. * Able to read and understand English proficiently (to be able to complete the multiple study questionnaires and instruments). EXCLUSION CRITERIA: An individual who meets any of the following criteria will be excluded from participation in this study: * Diabetes * Fasting glucose \>= 126 mg/dl or HbA1c \>= 6.5% or * Self-reported history of type 1 or type 2 diabetes. * Endocrine disorders, such as --Self-reported history of Cushing's disease, pituitary disorders, or hypo- and hyperthyroidism * TSH \= 10 uIU/mL * Pulmonary disorders --Self-reported history of chronic obstructive pulmonary disease or other lung disease that which would limit ability to follow the protocol (investigator judgment) * Cardiovascular diseases, --Self-reported history of coronary heart disease, heart failure, arrhythmias, and peripheral artery disease that which would limit ability to follow the protocol (investigator judgment) * Liver disease, * Advanced liver disease (as determined by history, labs, exams, and patient self-report) that which would limit ability to follow the protocol (investigator judgment) * AST or ALT elevations \> 3 times upper limit of normal * Gastrointestinal Surgery --Self-reported history of bariatric surgery * Renal disease * Self-reported history of renal replacement therapy * Abnormal kidney function (defined as eGFR \