What is the recommended fasting duration for triglycerides and lipoproteins?

• A. 6-8 hours
• B. 12-14 hours
• C. None required
• D. 24 hours

Answer: (B)

Triglycerides in the blood rise after a meal because of chylomicrons and other postprandial lipoproteins. To get a stable, comparable measurement of triglycerides and lipoprotein fractions, you want the blood drawn after a period of fasting so that recent dietary fat doesn’t skew the results. About 12 to 14 hours of fasting is commonly recommended because it allows postprandial lipemia to subside and reduces variability in the results. Shorter fasts, like 6–8 hours, can leave residual post-meal lipids and yield higher or more variable triglyceride levels. A 24-hour fast isn’t necessary and can be inconvenient without added benefit. None required would apply to nonfasting panels, but for accurate triglyceride and lipoprotein measurements, a 12–14 hour fast is the standard.