Can your meal choice fire up brown fat? new study investigates

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

Inclusion Criteria: * • Males and females * Between 18 and 45 years old. * For the lean group: BMI\<25.0 kg/m2 * For the group with overweight/obesity: BMI\>27.5 kg/m2 and a waist circumference of over 94 cm (men) or 80 cm (women). Exclusion Criteria: * • Inability to have PET/CT (claustrophobia, weight \> 150 kg); * Pregnancy and pregnancy-related conditions (postpartum/lactation during the last 12 months, or planning to become pregnant soon); * Major alterations in the menstrual cycle (e.g., amenorrhea); * Use of nicotine-based products; * Hypo- or hyper- thyroidism (medical history, TSH, T3 or T4 levels out of the normal range); * Diabetes mellitus (fasting Hb1Ac \>6.5% or fasting glycaemia\>125 mg/dL) or abnormal oral glucose tolerance test (2h OGTT \> 7.8 mmol/L); * Hypertension (blood pressure \> 160/100 mmHg) or abnormal cardiovascular status (arrhythmia and/or long QTc in ECG, abnormal cardiac murmur, previous history of cardiovascular disease); * Abnormal coagulopathy (e.g., clotting abnormality); * Malignancies, immunological, autoimmune and primary/secondary immunodeficiency disorders (including or not any active treatment). * Virus or bacterial infection (both asymptomatic and symptomatic picture) within the 30 days prior to the study start; * Episode of fever or major surgery, burns and traumas within the month prior to the study start * Chronic infections requiring chronic antibiotic or anti-viral treatment * Whole blood donation in the last 3 months (\>400 mL of blood) or plans for blood donation during the entire protocol period * Weight change (intentional or not) over the last 6-months \> than 5% of body weight, or plan to lose weight during the study, * Use of any medication that, in the opinion of local clinician/researcher, would negatively affect or mitigate full participation and completion, or could influence the study results. This especially applies to the use of β or α adrenergic receptors agonists/antagonists (e.g., β-blockers). In addition, participants in use of medication for glucose control or weight loss such as GLP-1 analogs will not be included.