Evaluation of Biomarkers for Predicting Macronutrient Intake

The goal of this clinical trial is to establish the relationship between macronutrient food intake and the resulting blood and intersticial fluid (ISF )levels of small molecule markers, as well as, validate wearable optical readers and data fusion algorithms to accurately predict individual-specific macronutrient availability in real time. The study involves 1 screening visit of approximately 2 hours and up to 4 study days of approximately 14 hours. Subjects will be asked to arrive in the fasted state on all study days. Fasting prior to screening is not required. On the screening visit, body weight, height, and body composition by Dual-energy X-ray absorptiometry (DXA) will be measured. In addition, habitual dietary intake, physical activity level (PASE), and quality of life (SGRQ-C) will be assessed.

Inclusion criteria * Ability to walk, sit down and stand up independently * Age 50-75 years old * Ability to lie in supine or slightly elevated position for approximately 13 hours * BMI between 25 and 35 * Willingness and ability to comply with the protocol Exclusion Criteria * Established diagnosis of malignancy * Established diagnosis of Insulin or non-Insulin Dependent Diabetes Mellitus * History of untreated metabolic diseases including hepatic or renal disorder * Currently on anticoagulants (i.e., warfarin, factor X inhibitors or direct thrombin inhibitors) * History of deep vein thrombosis, pulmonary embolisms, or known clotting disorders * Presence of acute illness or metabolically unstable chronic illness * Recent myocardial infarction (less than 1 year) * Known allergy or intolerance to any of the meal components * Any other condition according to the PI or nurse that was found during the screening visit, that would interfere with the study or safety of the patient * Failure to give informed consent or Investigator\'s uncertainty about the willingness or ability of the participant to comply with the protocol requirements