Why does fish oil reduce triglycerides?

Beyond its ability to slash risk for cardiovascular events, omega-3 fatty acids from fish oil also reduce triglycerides.

There's no remaining question that omega-3s do this quite effectively. After all, the FDA approved prescription fish oil, Lovaza, to treat a condition called familial hypertriglyceridemia, an inherited condition in which very high triglycerides in the 100s or 1000s of milligrams typically develop.

The omega-3 fraction of fatty acids are unique for their triglyceride-reducing property. No other fraction of fatty acids, such as omega-6 or saturated, can match the triglyceride-reducing effect of omega-3s.

But why does fish oil reduce triglycerides?

First of all, what are triglycerides? As their name suggests, triglycerides consist of three ("tri-") fatty acids lined up along a glycerol (sugar) "backbone." Triglycerides are the form in which most fatty acids occur in the bloodstream, liver, and other organs. (Fatty acids, like omega-3, omega-6, mono- or polyunsaturated, or saturated, rarely occur as free fatty acids unbound to glycerol.) In various lipoproteins in the blood, like LDL, VLDL, and HDL, fatty acids occur as triglycerides.

Of all lipoproteins, chylomicrons (the large particle formed through intestinal absorption of fatty acids and transported to the liver via the lymph system) and VLDL (very low-density lipoprotein, very low-density because they are mostly fat and little protein) particles are richest in triglycerides. Thus, we would expect that omega-3s exert their triglyceride-reducing effect via reductions in either chylomicrons or VLDL.

Indeed, that seems to be the case. The emerging evidence suggests that omega-3 fatty acids from fish oil reduce triglycerides through:

--Reduced VLDL production by the liver (Harris 1989)
--Accelerating chylomicron and VLDL elimination from the blood
--Activation of peroxisome proliferator-activated receptor gamma (PPAR-gamma)--Omega-3s ramp up the cellular equipment used to convert fatty acids to energy (oxidation) (Gani 2008)

Combine omega-3 fatty acids from fish oil with wheat elimination and you have an extremely potent means of reducing triglycerides. Read a previous Heart Scan Blog post here to read how a patient reduced triglycerides 93.5% from 3100 mg/dl to 210 mg/dl in just a few weeks using fish oil and wheat elimination.