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.