Sugar test during surgery may unlock secrets of fatty liver disease

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

Inclusion Criteria: To be eligible to participate in this study, a subject must meet all of the following criteria: Adult individuals, age \>35 \< 65 years old. Stable weight (no more than 3% TWL of initial body weight from screening to surgery) Subjects should be able to give informed consent Subjects agree to have tissue biopsies performed during surgery, that is 2 liver, subcutaneous, visceral and omental biopsies plus a one-time jejunal biopsy. For obese non-MASLD patients: * Adult individuals, age \>35 \< 65 years old. * BMI ≥ 40 kg/m², or a BMI ≥ 35 kg/m² with an obesity-related comorbidity * No MASLD based on Fibroscan * Estimated glomerular filtration rate (eGFR) \> 60mL/min/1.73m2 For obese MASLD patients: * MASLD diagnosis according to Fibroscan * Compensated liver disease with the following hematologic and biochemical criteria on entry into study: * ALAT \<10x ULN * Hemoglobin \> 11g/dL for females and 12 g/dL for males * White blood cell (WBC) \> 2.5 K/ μL * Neutrophil count \> 1.5 K μL * Platelets \> 100 K/μL * Total bilirubin \<35 μmol/L * Albumin \>30 g/L * TP \>80% or INR \<1.4 * Serum creatinine \<1.3 mg/dL (men) or \<1.1 mg/dL (women) or * Estimated glomerular filtration rate (eGFR) \> 60mL/min/1.73m2 Exclusion Criteria: A potential subject who meets any of the following criteria will be excluded from participation in this study: * Use of metformin and SGLT2/ exogenous insulin/GLP-1 RA * Primary lipid disorder * Known genetic basis for insulin resistance or glucose intolerance * All medical and psychiatric conditions except for obesity related diseases. * Uncontrolled hypertension (RR \> 150/95 mmHg) * Chronic kidney disease (creatinine \> 150 umol/L) * Pregnancy, females who are breastfeeding * Evidence of another form of liver disease * History of sustained excess alcohol ingestion: daily consumption \>30g/day (3 drinks per day) for males and \>20 g/day (2 drinks per day) for females * Significant systemic or major illnesses other than liver disease, including congestive heart failure (class C and D of the AHA), unstable coronary artery disease, cerebrovascular disease, pulmonary disease, kidney failure, organ transplantation, serious psychiatric disease, active malignancy, compromised immunity * Body mass index (BMI) \>45 kg/m2 * Type 1 or type 2 diabetes * Hemostasis disorders or current treatment with anticoagulants * Known heart failure * Contra-indication for liver biopsy History of/or current cardiac dysrhythmias and/or a history of cardiovascular events including myocardial infarction, except patients with only well-controlled hypertension