Guide to Triglycerides

WRITTEN BY

The Levels Team

Updated: 05/22/2025|12 min read

Summary

Triglycerides are your body's primary form of stored energy, transported through the bloodstream as part of lipoproteins. Your body's triglyceride level reflects how well it processes and stores energy from both dietary fats and carbohydrates.

Why It Matters

Triglycerides provide insight into metabolic health beyond traditional cholesterol markers. Your body creates triglycerides through two paths: packaging dietary fats into chylomicrons in your intestines and synthesizing them in your liver from excess carbohydrates and fatty acids. While this storage system is essential, elevated blood triglycerides often signal metabolic dysfunction.

High triglycerides directly impact cardiovascular risk by altering how other lipids behave. They cause high-density lipoprotein (HDL, or beneficial cholesterol) particles to become triglyceride-heavy and less protective, and transform low-density lipoprotein (LDL, or potentially harmful cholesterol) into smaller, denser, more dangerous particles. When triglyceride-rich particles enter artery walls, they contribute to plaque formation and trigger inflammatory responses, making them an important marker for both current health status and future disease risk.

The relationship between triglycerides and insulin resistance is also telling. When insulin resistance develops, three problems occur: glucose can't easily enter muscle cells and returns to the liver for triglyceride production; insulin becomes less effective at suppressing fat cell breakdown, releasing more fatty acids to the liver; and the liver itself becomes resistant to insulin's normal suppression of triglyceride production. This creates a vicious cycle where insulin resistance drives high triglycerides, which in turn worsens metabolic health.

Clinical Ranges

Lab Reference Ranges:

• 10-19 Years: < 90 mg/dL
• ≥20 Years: < 150 mg/dL

Lifestyle Factors That Can Impact It

Factors that help lower triglycerides:

• Regular aerobic exercise increases lipoprotein lipase activity, helping clear triglycerides from blood.
• The Mediterranean diet reduces refined carbohydrates while providing beneficial fats.
• Fiber-rich foods slow glucose absorption and reduce triglyceride formation.
• Time-restricted eating helps regulate metabolic processes affecting triglyceride production.
• Omega-3-rich foods directly reduce liver triglyceride synthesis.

Factors that raise triglycerides:

• Excessive fructose/high fructose corn syrup drives liver triglyceride production more than other sugars.
• Post-meal high glycemic loads increase chylomicron production.
• Chronic sleep disruption alters hormones that regulate fat metabolism.
• Heavy alcohol use both increases production and impairs clearance of triglycerides.

Other Factors That Can Impact It

Genetic Factors

• Familial hypertriglyceridemia: Increases triglycerides significantly
• Genetic variations in lipid metabolism: Can increase or decrease triglycerides, depending on specific variation
• Inherited disorders of fat metabolism: Usually increases triglycerides

Medical Conditions

• Hypothyroidism: Increases triglycerides due to slowed metabolism
• Diabetes: Increases triglycerides, especially with poor control
• Lupus: associated with elevated triglycerides
• Rheumatoid arthritis: associated with elevated triglycerides
• Kidney disease: Often increases triglycerides
• Pregnancy: Typically increases triglycerides, especially in third trimester

Medications

• Oral retinoids: Can increase triglycerides
• Steroids: Can increase triglyceride levels
• Immunosuppressants: Can elevate triglycerides
• Beta-blockers: May slightly increase triglycerides
• Diuretics: High doses, especially of thiazides, may increase triglycerides
• Birth control pills: Often increase triglycerides
• Corticosteroids: Typically increase triglycerides
• Some HIV medications: May increase triglycerides

Supplements

• Fish oil: Decreases triglycerides, especially at higher doses
• Niacin: Decreases triglycerides significantly
• Berberine: Decreases triglycerides moderately
• Red yeast rice: Decreases triglycerides moderately
• Bergamot: May decrease triglycerides and increase HDL
• Curcumin: May decrease triglycerides and increase HDL

Testing Accuracy and Stability

Triglyceride tests are generally accurate under proper testing conditions. However, some factors may affect your results.

Factors That Can Affect the Accuracy of Your Test

• If you ate before the test (fasting 8-12 hours is recommended)
• You have an acute Illness or infection
• Pregnancy
• Recent alcohol consumption

How it Relates to Other Markers

• High triglycerides with low HDL: Classic insulin resistance pattern; high ratio (>3.0) suggests metabolic dysfunction.
• High triglycerides with normal total cholesterol: May indicate early metabolic issues before other lipids change. Could also indicate lifestyle factors like smoking or heavy alcohol use. Could also be related to autoimmune conditions, medications, or genetic factors.
• High triglycerides with small dense LDL: Pattern suggesting significant metabolic dysfunction.
• Normal triglycerides with high ApoB: May indicate need to look at particle numbers rather than just lipid content.

Follow-up Considerations

When Re-Testing May be Appropriate

• Normal (< 150 mg/dL): Males 45 and up and females 55 and up, get tested annually; others, every five years if no risk factors
• Borderline (150-199 mg/dL): Every 6-12 months, more frequently if implementing changes
• High (200+ mg/dL): Every 3-6 months until improved

Additional Testing Your Doctor May Consider

• Advanced lipoprotein particle testing
• Insulin levels, if not already tested
• Thyroid function tests
• Liver function evaluation

When Additional Care May be Warranted

• Borderline: If levels don't improve with lifestyle changes after 6 months
• High: Medical evaluation needed, especially if:
  • Other lipid abnormalities present
  • Diabetes or heart disease present
  • Family history of early heart disease
  • Multiple risk factors exist

Bibliography