Cod Liver Oil
Supplements
About
Cod liver oil can be obtained from eating fresh cod liver or by taking supplements.
Cod liver oil is used as a source of vitamin A and vitamin D, and to treat high cholesterol and high triglyceride levels, kidney disease in people with diabetes, high blood pressure, heart disease, osteoarthritis, rheumatoid arthritis, depression, an autoimmune disease called systemic lupus erythematosus (SLE), glaucoma, and middle ear infections (otitis media). It is also used to prevent respiratory infections, and an age-related eye condition called macular degeneration.
Some people put cod liver oil on their skin to speed healing of wounds, burns, and rashes.
How it works
Cod liver oil contains certain "fatty acids" that prevent the blood from clotting easily. These fatty acids also reduce pain and swelling.
Effectiveness
Not Proven
Age-related macular degenerationPeople who eat a lot of fish and take cod liver oil don't have a lower risk of developing this condition compared to people who just eat a lot of fish.
Taking cod liver oil by mouth might reduce a specific type of irregular heartbeat in some people. But it's not known if this reduces the risk of heart-related death. Taking cod liver oil by mouth does not seem to reduce irregular heartbeat in men with irregular heartbeat after a heart attack.
Taking cod liver oil has been linked with a 29% lower chance of older adults having depression symptoms.
Taking cod liver oil by mouth doesn't lower cholesterol levels in people with high cholesterol. But it might increase "good" high-density lipoprotein cholesterol levels in people with type 1 diabetes and high cholesterol. Also it might lower blood fats called "triglycerides" in men who have had a heart attack. But cod liver oil doesn't improve these outcomes in people with an inherited form of high cholesterol.
Taking cod liver oil by mouth seems to slightly lower blood pressure in healthy people and those with slightly high blood pressure. But it's not clear if this reduction is clinically meaningful for people with very high cholesterol.
Some people with inflammatory bowel disease have joint pain. Taking cod liver oil might reduce joint pain in some people with this condition.
Taking cod liver oil along with an NSAID doesn't reduce swelling in people with osteoarthritis better than taking an NSAID alone.
Taking cod liver oil and a multivitamin might reduce the need to use medicine to treat ear infections in young children by about 12%.
Giving young children cod liver oil and a multivitamin seems to reduce the number of doctor's office visits for airway infections.
Taking cod liver oil might decrease pain, morning stiffness, and swelling in some patients with rheumatoid arthritis. Also, taking cod liver oil and fish oil seems to reduce the need to use medicine to treat joint swelling in people with this condition.
Taking cod liver oil seems to increase blood levels of vitamin D in some people. But it's not clear if cod liver oil increases vitamin D to normal levels in people with low levels of vitamin D.
Concerns
Likely safe
Cod liver oil is LIKELY SAFE for most adults and children when taken by mouth. It can cause side effects including belching, bad breath, heartburn, loose stools, and nausea. Taking cod liver oil with meals can often decrease these side effects
Possibly unsafe
High doses of cod liver oil are POSSIBLY UNSAFE. They might keep blood from clotting and can increase the chance of bleeding. Vitamin A and vitamin D levels might also become too high with high doses of cod liver oil.The safety of cod liver oil when used on the skin is unknown.
Warnings
Pregnancy and breast-feeding: Cod liver oil is POSSIBLY SAFE when used in amounts that provide no more than the recommended daily intakes of vitamin A and vitamin D. Cod liver oil isPOSSIBLY UNSAFEwhen taken in larger amounts. Women who arepregnantorbreast-feeding should not take cod liver oil that provides more than about 3000 mcg of vitamin A and 100 mcg of vitamin D.Are there any interactions with medications?
Diabetes: There has been some concern that cod liver oil or other fish oils might increase blood sugar in people with diabetes. But there is no strong research that supports this concern. High blood pressure: Cod liver oil can lower blood pressure and might cause blood pressure to go too low if used along with medications for high blood pressure. Be careful when using cod liver oil if you are taking high blood pressure drugs.
Interactions
Moderate
Medications that slow blood clotting (Anticoagulant / Antiplatelet drugs)Cod liver oil seems to decrease blood pressure. Taking cod liver oil along with medications for high blood pressure might cause your blood pressure to go too low.Some medications for high blood pressure include captopril (Capoten), enalapril (Vasotec), losartan (Cozaar), valsartan (Diovan), diltiazem (Cardizem), amlodipine (Norvasc), hydrochlorothiazide (HydroDIURIL), furosemide (Lasix), and many others.Cod liver oil might slow blood clotting. Taking cod liver oil along with medications that also slow clotting might increase the chances of bruising and bleeding.Some medications that slow blood clotting include aspirin, clopidogrel (Plavix), diclofenac (Voltaren, Cataflam, others), dipyridamole (Persantine), ibuprofen (Advil, Motrin, others), naproxen (Anaprox, Naprosyn, others), dalteparin (Fragmin), enoxaparin (Lovenox), heparin, ticlopidine (Ticlid), warfarin (Coumadin), and others.