LDL & Fish Oil

Low-density lipoprotein, or LDL, is widely known as the potentially harmful form of cholesterol in the human body. High LDL levels are linked to heart disease and other health problems. Having yielded some positive findings on the possible effect of certain fish oils on the occurrence of and prognosis for heart disease, research on the topic is continuing. Data regarding fish oil's impact on LDL cholesterol remain mixed.

Cholesterol

Cholesterol is a lipid molecule that is widely incorporated within the structures of both human and animal cells. Cholesterol is produced within the body and can also be ingested from meat and animal products. The liver, the single most important site for cholesterol synthesis in the body, produces all the cholesterol the body needs for healthy functioning. Once produced, cholesterol is transported across the body to the cells that need it.

LDL and HDL

Cholesterol molecules aren't released freely into the bloodstream; rather they "catch a ride" on particles called low-density lipoproteins. LDL molecules carry cholesterol from the liver and a few other production sites into the blood and deposit the cholesterol where it is needed. Another set of carriers, high-density lipoproteins or HDLs, transport cholesterol molecules away from cells when they're no longer needed and returns them to the liver for excretion.

The Role of LDL in Disease

While LDL particles are tasked with delivering cholesterol to cells in need, LDL doesn't always arrive as planned. While traveling through the bloodstream, LDL particles can become lodged inside small imperfections on the walls of arteries. Over time, these deposits can build up to form plaques and cause secondary inflammation, both of which narrow the artery and restrict blood flow. This can cause cardiovascular disease and other dangerous health conditions.

Fish Oils

Intensive research on the possible health effects of fish oils began in the 1990s. Researchers focused on a group of oils known as omega-3s and on several members of the group that seemed to hold the most significance for health: eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), which are found naturally in certain fish, and alpha-linoleic acid (ALA), which is derived from plants. Australian research reported in the "Journal of Nutrition" in 2008 showed that fish oils reduced LDL cholesterol and triglyceride levels, both risk factors for heart disease. Earlier research in the the journal "Arteriosclerosis, Thrombosis, and Vascular Biology" showed that EPA and DHA intake from 0.5 to 1.8 g per day significantly reduced the likelihood of death due to heart disease. Largely in response to such findings, fish oils and ALA have become popular nutritional supplements.

Divergency of Findings

Other data have been more ambiguous. Several studies have found that fish oil supplementation apparently increased, rather than decreased, blood levels of LDL cholesterol. In most of these studies, triglyceride levels decreased, indicating that fish oil supplements may still be worthwhile in certain patients for reducing overall heart disease risk. Research examining the effects of fish oil on LDL levels and overall cardiovascular disease continues. Discuss the possible risks and benefits of fish oil supplementation with your doctor before beginning any regimen.