Triglycerides

Blood fats that come from dietary fat or are made in the liver – among other things from excess carbohydrate and alcohol. Triglycerides are looked at in cardiovascular and pancreatic diagnostics. How they are to be read is set out in your findings report. They are considered together with the blood sugar values.

What triglycerides do in the body

Triglycerides consist of glycerol and three fatty acids and are the body's most important energy reserve, stored in fat tissue. In the blood they travel in two kinds of particle: after a meal, the gut packs dietary fat into chylomicrons, which reach the blood via the lymph; the liver releases VLDL, which contains triglycerides made from fatty acids from fat tissue and from excess carbohydrates, fructose and alcohol. On the capillary walls of muscles, heart and fat tissue, lipoprotein lipase splits the triglycerides, and the cells take up the fatty acids – to burn or to store them. Insulin activates this pathway in fat tissue and at the same time slows the release of stored fatty acids.

Low triglycerides – what happens in the body?

Low triglycerides show that few chylomicrons and little VLDL are travelling in the blood and that lipoprotein lipase is distributing the fatty acids to the tissues promptly. This is to be expected when fasting, with high insulin sensitivity and with regular exercise, when muscles burn a lot of fatty acids. Low values also occur with malnutrition, an overactive thyroid and disorders of fat absorption in the gut, and very rarely with inherited disorders of lipoprotein formation. On their own, low triglycerides usually have no significance of their own.

High triglycerides – what happens in the body?

Raised triglycerides arise when more triglyceride-rich particles are formed than broken down. With insulin resistance, insulin is less effective at slowing fat release from fat tissue; more fatty acids reach the liver, which exports them as VLDL or stores them, and at the same time high insulin there promotes the production of new fat. CETP then exchanges triglycerides for cholesterol from HDL and LDL – HDL falls, and small, dense LDL particles are formed. Very high values with many chylomicrons can inflame the pancreas and cause yellowish nodules in the skin. Causes include insulin resistance and diabetes, alcohol, an underactive thyroid, kidney disease, medications and inherited disorders of lipoprotein lipase.