Adaptation of Human Brown Adipose Tissue to Calorie Restriction

Inclusion Criteria: * Body mass index (BMI) of 27-40 kg/m², with a body fat percentage (determined by DXA, Hologic Wi) exceeding 25% in men and 30% in women. * Reported stable body weight over the preceding 3 months (body weight changes of less than 3%). * Laboratory safety test results (general biochemistry and complete blood count) within the normal reference range or with abnormalities deemed clinically insignificant by the medical research team and not requiring pharmacological treatment. * Adequate venous access for blood sampling required by the procedures described in this protocol and absence of needle, blood, or medical procedure phobia. * Readiness and ability to consume all foods included in the assessments and dietary intervention. * Ability to understand and comply with study procedures, as assessed by the research team. * Availability to participate in the study. * Commitment to completing the study regardless of the assigned group. Exclusion Criteria: * Diagnosis or presence of signs or symptoms that, in the opinion of the research team, may contraindicate the dietary intervention or any of the procedures included in the study. * Diagnosis or history of metabolic (including any type of diabetes mellitus), hematologic, pulmonary, cardiovascular, gastrointestinal, neurological, immune, hepatic, renal, urologic, or psychiatric diseases that could interfere with study outcomes or protocol adherence. * History of any surgical procedure that, in the opinion of the…