Fish oil can help reduce the level of triglycerides in your blood, but its impact on your cholesterol is still debatable. While some research has proved promising, the National Institutes of Health labels fish oil as being just "possibly effective" at reducing high cholesterol. Like cholesterol, triglycerides are a type of blood lipid, or fat. Reducing the level of low-density lipoprotein, or LDL, cholesterol in your blood can lower your overall risk of developing heart disease. The same is true of triglycerides. Do not use fish oil supplements to reduce cholesterol without first consulting with your physician.
Cholesterol
Although LDL cholesterol increases your risk of heart disease, high-density lipoprotein, or HDL, cholesterol can help keep your arteries open and prevent plaque from adhering to your arterial walls. If you are over age 20, the National Institutes of Health recommends that you have your blood cholesterol checked every five years. Your doctor will give you a lipoprotein profile that lists your total levels of LDL, HDL and triglycerides. Your total cholesterol level should be less than 200 milligrams per deciliter, and your LDL level should be under 100 mg/dL.
Fish Oil
Fish oil contains two types of omega-3 fatty acids, docosahexaenoic acid, or DHA, and eicosapentaenoic acid, or EPA. Omega-3 fatty acids are essential polyunsaturated fats that your body needs to perform vital functions, even though it is unable to produce it on its own. All omega-3 fatty acids that your body needs you must obtain through dietary or supplemental sources.
Dosing
Dosing recommendations for fish oil vary. If you have high triglycerides as well as high cholesterol, the NIH notes that researchers use a daily dose of fish oil supplements providing 1,800 to 2,160 mg of EPA and 1,200 to 1,440 mg of DHA, combined with 900 to 1,200 mg of garlic powder. There are no official dosing recommendation for using fish oil to treat cholesterol alone.
Evidence
The January 2010 issue of "Current Atherosclerosis Reports" contains a meta-review, a study of past studies, on fish oil. One study analyzed the blood levels of 14,981 Japanese patients who entered the study with untreated high cholesterol and high triglycerides. All patients received statins, cholesterol-lowering medication, and one group also received 1,800 mg of EPA daily. Researchers followed the participants for five years. The authors write that EPA provided numerous cardiovascular benefits, including reducing the risk of death from cardiovascular causes, but there was "no clinically meaningful changes in lipids."
Warning
High doses of fish, more than 3 grams per day, oil may prevent your blood from clotting and can increase your risk of bleeding. Fresh fish may contain certain environmental contaminants. Typically the fish oil contained in supplements is treated to remove such contaminants. Fish oil can also cause gas or bloating and may interact with diabetes drugs, cholesterol medication and blood thinners.
References
- MedlinePlus: Fish Oil
- National Cholesterol Education Program; High Blood Cholesterol: What You Need to Know; May 2001
- University of Maryland Medical Center: Omega-3 Fatty Acids
- American Heart Association: Fish and Omega-3 Fatty Acids
- "Current Atherosclerosis Reports"; Fish Oil for Primary and Secondary Prevention of Coronary Heart Disease; Eli M. Roth, M.D., et al.; January 2010
