Evaluating Body Composition for Obesity

Inclusion Criteria: * Being willing to provide written informed consent prior to participation Being willing to complete the study visits and comply with the study procedures * Being willing to travel to the various study locations for On-site, DXA, MRI, and Phlebotomy visits * Being willing to change into appropriate form-fitting clothing for 3DO assessments and/or appropriate gowns for DXA and MRI imaging * Must have a BMI within the range of 18.5 - 45 kg/m2 * Being willing to refrain from all food, drink, and substances for 8 hours prior to the On-site visit(s) and phlebotomy visit * Being willing to refrain from all food, drink, and substances for 4 hours prior to the DXA and MRI scan visits * Being willing to refrain from any exercise or vigorous physical activity for 24 hours prior to all visits * Stable weight (no more than 5 kg change) for 3 months prior to screening * If recruited in the Phoenix, AZ area, participants must be willing to drive yourself to the Phoenix Office location for the On-site Visits 1 and 2 (if applicable) located at the Exponent Phoenix Office. Exclusion Criteria: * Being pregnant or attempting to become pregnant * Having medical implants, such as a pacemaker or metal joint replacements, or other metal implants contraindicated for MRI * Cosmetic implants, such as breast implants * Having a height greater than DXA scanning limit (77 inches) * Having a body weight greater than indicated for the equipment (400 lbs) * Prior amputation or major body-altering surgery that could invalidate body composition estimates * Having claustrophobia or a history of claustrophobia * Known HIV infection * Known Lipodystrophy * Known hydration abnormality (e.g., significant edema, end-stage renal disease, end-stage liver disease) * Severe illness or life-threatening conditions such as end-stage kidney, liver, lung disease, NYHA III-IV heart failure, or active malignancy