Synthetic Omega-3 Fish Oil Product Has Unexpected Side Effects

In 2005 the United States Food and Administration approved a synthetic fish oil made by pharmaceutical giant GlaxoSmithKline and marketed under the trade name Lovaza. This chemically modified form of fish was advertised as the first clinically proven treatment for high triglycerides.

Well, almost the very clinically proven treatment. Diabetics who lower their blood sugar levels and anyone who simply eats less is likely to enjoy lower triglyceride levels.

Triglycerides are both found in food and made by our bodies. When we eat foods that contain triglycerides, these bulky fat acids are absorbed by specialized cells in the lining of the intestine called enterocytes. They enter the lymphatic system and are carried near major blood vessels.

Some of the triglycerides leaking into the major blood vessels reach the liver where they are transformed into a kind of cholesterol called VLDL, or very low-density lipoprotein. Even though very low-density lipoprotein is even lower-density than LDL, or low-density lipoprotein, VLDL does not cause heart or cardiovascular disease.

When we eat more fat or carbohydrate than our bodies need, the excess calories become triglycerides for storage inside the liver and fat cells. In times of stress, they are easily converted back into the glucose sugar the body uses for fuel.

People who eat too much, or who have diabetes, tend to have high triglycerides. There is no direct effect of triglycerides on cardiovascular health, either, although people who have very high levels of triglycerides tend also to have low levels of HDL cholesterol. About 60% of the triglycerides in the bloodstream are derived from excess food consumption.

Any kind of fish oil can lower triglycerides but only Lovaza has been subjected to rigorous clinical testing. Ironically, this synthetic fish oil is probably less effective than regular fish oil. Lovaza is made by boiling the fatty acids in fish oil with alcohol to make a shelf-stable form of omega-3 fatty acids known as fish oil esters.

This synthetic fish oil is more shelf-stable than regular fish oil, but it is also less available to the body because the intestine has to process the esters into their constituent fatty acids before the body can use them.

And since high triglycerides can also be lowered by dieting or regular fish oil, one has to wonder why one would spend $250 on a 30-day supply of Lovaza instead of $25 on a 30-day supply of fish that does the same thing.

There is one claim about Lovaza made in natural health news that is true but misleading. Many natural health gurus claim that people who use Lovaza get lab results showing higher levels of LDL cholesterol. That's true. However, many people who use fish oil also get lab results showing higher levels of LDL cholesterol.

Labs "guesstimate" LDL cholesterol

That isn't because they actually have higher levels of LDL cholesterol. It is because medical labs usually don't actually measure LDL cholesterol. They measure total cholesterol and triglycerides and then "guesstimate" LDL cholesterol as 1/5 of the difference, the other 4/5 being the harmless VLDL cholesterol. If triglycerides go down, estimated LDL cholesterol will go up, whether actual LDL cholesterol goes up or not.

If you are really concerned about cholesterol, the test you need is not LDL cholesterol. It is a test for apo-A cholesterol, which is more directly linked with heart disease. But that test costs about 25 times as much as the estimate of LDL.

Especially if you would have to pay the full price out of pocket for Lovaza, ask your doctor if you cannot just try a high-quality fish oil supplement first. And be sure your doctor knows that labs estimate LDL cholesterol levels, or ask for a more appropriate apo-A test.

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