What is Triglycerides?
Triglycerides (triacylglycerols) are glycerol esters of three fatty acid chains — the principal form of dietary fat storage and the primary energy substrate delivered by the hepatic VLDL secretory pathway to peripheral tissues. Postprandially, dietary triglycerides are packaged into chylomicrons in the intestine and cleared from the circulation within 4–6 hours by lipoprotein lipase on endothelial surfaces. In the fasting state, serum triglycerides reflect predominantly hepatic VLDL-TG production, regulated by insulin and dietary carbohydrate intake. Elevated VLDL production from caloric excess, insulin resistance, or genetic dyslipidaemia (familial hypertriglyceridaemia, lipoprotein lipase deficiency) produces fasting hypertriglyceridaemia. Triglycerides above 400 mg/dL invalidate the Friedewald LDL-C equation; above 1,000 mg/dL carry significant pancreatitis risk.