According to WebMD, cod liver oil is beneficial for lowering blood fat known as triglycerides when it is taken orally. It is also believed to help regulate high blood pressure and aid in the treatment of diabetes-related kidney disease symptoms.
WebMD explains that cod liver oil contains fatty acids that are helpful in keeping the blood from clotting. Although some pain and swelling is also thought to be relieved by these acids, they do not seem to be effective for reducing pain associated with arthritis. People use cod liver oil on their skin to help speed up the healing of wounds. The benefits of the oil can also be experienced by taking supplements or eating fresh cod liver. Other uses of cod liver oil are still being evaluated for their effectiveness. This includes treatment for depression, children's ear infections, systemic lupus, heart disease, glaucoma and an irregular heartbeat.
WebMD notes that cod liver oil in moderate doses is generally safe for public use. Some of the minor side effects are nosebleeds, heartburn, bad breath and belching. These side effects can probably be reduced by taking the oil with meals; however, high doses of cod liver oil may possibly be unsafe, increasing the chances of bleeding due to a loss of the blood's ability to clot.