High Triglycerides: What Causes Them and How Can You Lower Them?

What are triglycerides, and why is it important to monitor them?

Triglycerides are blood lipids produced from dietary calories that the body does not use immediately. Stored in fat cells, they serve as an energy reserve that can be tapped between meals. High levels promoteatherosclerosis —the hardening and thickening of artery walls—and increase the risk of cardiovascular disease, stroke, and acute pancreatitis. Reference values according to HAS/ESC recommendations:

• Normal: less than 150 mg/dL (1.7 mmol/L).
• Upper limit: 150–199 mg/dL.
• High: 200–499 mg/dL.
• Very high (risk of pancreatitis): ≥ 500 mg/dL.

Hypertriglyceridemia is often asymptomatic and is discovered during a routine lipid profile. It is frequently associated with a decrease in protective HDL cholesterol.

What causes elevated triglycerides?

Hypertriglyceridemia is most often multifactorial:

• A diet high in simple sugars, alcohol, and saturated fats.
• A sedentary lifestyle and being overweight, particularly abdominal obesity.
• Type 2 diabetes or insulin resistance— diabetes is one of the most common secondary causes.
• Hypothyroidism, kidney failure, or nephrotic syndrome.
• Certain medications (corticosteroids, beta-blockers, antiretrovirals).
• Genetic factors: familial hypertriglyceridemia, mixed dyslipidemia.

It is important to note that hypertriglyceridemia is often part of a broader metabolic syndrome, involving abdominal obesity, insulin resistance, high blood pressure, and low HDL. Treating the underlying cause is often more effective than targeting triglycerides alone.

How can triglycerides be reduced through diet?

Dietary changes are often sufficient to normalize moderately elevated levels:

• Eliminate or drastically reduce added sugars (sodas, juices, candy, and processed desserts).
• Limit alcohol, which directly stimulates the liver’s production of triglycerides.
• Increase dietary fiber (legumes, whole grains, vegetables), which slows the absorption of sugars.
• Choose unsaturated fats (olive oil, avocados, fatty fish).
• Replace refined carbohydrates with complex carbohydrates that have a low glycemic index.

A weight loss of 5 to 10 percent of body weight reduces triglycerides by an average of 20 percent, regardless of the diet followed. This reduction is due to decreased insulin resistance, which is the main driver of excessive triglyceride production by the liver in obesity. Spreading out meals to avoid postprandial blood sugar spikes also helps stabilize triglyceride levels.

Which dietary supplements help lower triglycerides?

Several supplements have documented efficacy:

• Omega-3 (EPA/DHA): Lowering triglycerides is the best-documented effect of high-dose omega-3s. At doses of 2 to 4 g per day, they can lower triglycerides by 15 to 30 percent.
• Niacin (vitamin B3): Reduces triglycerides and raises HDL, but high-dose use requires medical supervision (hot flashes, possible liver toxicity).
• Psyllium and soluble fiber: limit the intestinal absorption of fats and carbohydrates.
• Plant sterols: reduce the absorption of dietary cholesterol and triglycerides.

These supplements are intended to support lifestyle changes, not to replace them.

What impact do stress and physical activity have on triglycerides?

Chronic stress raises cortisol levels and promotes risky behaviors (sugary foods, a sedentary lifestyle, alcohol) that increase triglycerides. Conversely, regular aerobic physical activity (brisk walking, swimming, cycling) is one of the most effective ways to lower them: 150 minutes per week of moderate-intensity exercise can lower triglycerides by 10 to 20 percent over several weeks, regardless of weight loss.

When should you see a doctor for high triglycerides?

A doctor’s visit is necessary if triglyceride levels exceed 200 mg/dL despite dietary changes, if the level is higher than 500 mg/dL (risk of acute pancreatitis), or if other associated cardiovascular risk factors are present (high blood pressure, diabetes, smoking). The doctor may prescribe fibrates or high-dose omega-3 supplements. Regular lipid monitoring is still necessary even after levels have returned to normal.