Metabolic Heterogeneity Underlying Hypertriglyceridemia: Hepatic Triglyceride Biosynthesis in Humans With Different Insulin Resistance Phenotypes

Inclusion Criteria: * Ability to give informed consent * Overweight, defined as BMI 25-30 kg/m2 * Modest hypertriglyceridemia, defined as fasting plasma triglycerides 1.5-3.0mM * High risk of insulin resistance, defined as fasting plasma insulin \>64pM * Stable weight for at least 3mo prior to participation Exclusion Criteria: * Active or chronic liver disease, kidney disease, congestive heart failure, unstable angina, history of acute cardiovascular events within 6mo of screening, history of seizures or syncope, or an active infection requiring antimicrobial therapy; * Use of insulin, thiazolidinediones, SGLT2 inhibitors, or sulfonylureas; * Use of fibrates, omega 3 (fish oil), niacin, or PCSK9 antagonists; * Use of systemic glucocorticoids within 60d prior to participation; * Hematocrit \<35%; * Pregnancy of breastfeeding; * Active tobacco use, excessive alcohol intake (\>14U/wk), or history of drug abuse.