Advancing Precision Nutrition: Wearable Technology for Noninvasive Insulin Monitoring

Inclusion criteria: * Age * 18-30 years old * 50-90 years old * BMI between 22 and 35 kg/m2 * Ability to walk, sit down, and stand up (independently or with a walking assistance device) * Willingness to lay supine in bed for up to 9 hours * Willingness and ability to comply with the protocol Exclusion criteria * Known allergy to any of the components of the meal or agents used for the application of the devices * Sunflower oil * Maltodextrin * Whey protein * Pilocarpine solutions * Established diagnosis and active treatment of chronic disease: insulin-dependent diabetes, active malignancy, heart failure, kidney disease, liver disease, HIV/AIDS, asthma (moderate to severe), Hep (A, B, or C) * History of untreated metabolic disease including hepatic or renal disorder * Presence of acute illness or metabolically unstable chronic illness * Active dependence on alcohol or drugs * Use of a short course of oral corticosteroids within 4 weeks preceding study day * Current use of long-term oral corticosteroids * Presence of fever within the last 3 days * Planned elective surgery requiring 2 or more days of hospitalization during the entire study * (Possible) pregnancy (confirmed via urine pregnancy test for females 18-30 years) * Failure to give informed consent or Investigator's uncertainty about the willingness or ability of the subject * Any 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