Cod liver oil can be obtained from eating fresh cod liver or by taking supplements.

Cod liver oil is used for high cholesterol, high triglycerides, kidney disease in people with diabetes, high blood pressure, heart disease, osteoarthritis, depression, an autoimmune disease called systemic lupus erythematosus (SLE), glaucoma, and middle ear infections (otitis media).

Some people put cod liver oil on their skin to speed wound healing.

When taken in appropriate doses by mouth, cod liver oil seems to help lower high triglycerides (a type of blood fat), lower high blood pressure, and treat some symptoms of kidney disease related to diabetes. It doesn’t seem to lower high cholesterol or reduce arthritis pain. Other uses are still under investigation.

How does it work?
Cod liver oil contains certain “fatty acids” that prevent the blood from clotting easily. These fatty acids also reduce pain and swelling.
For lowering triglycerides: 20 mL of cod liver oil per day.
For high cholesterol: 30 mL of cod liver oil per day.
For lowering blood pressure: 20 mL of cod liver oil per day.

The recommended one teaspoon (two capsules) daily of cod liver oil (5 ml) of the most commonly used Norwegian brand (Möller’s, Axellus AS, Oslo) contains 10 μg (400 IU) of vitamin D₃, 250 μg of vitamin A, 10 mg of vitamin E and 1.2 g of the omega-3 fatty acids EPA and DHA.