What Is Cod Liver Oil Good For?

1. Boosts immunity: Cod liver oil is rich in vitamin A, which is a potent antioxidant that helps improve immunity by reducing the free radical damage to cells.
2. Heart health: Omega-3 fatty acids reduce bad cholesterol levels, improve good cholesterol levels, and slow the process of atherosclerosis (fat buildup in blood vessels). Moreover, they help maintain the inner lining of blood vessels.
3. Lowers cancer risk: Studies have suggested that vitamin D and omega-3 fatty acids may play a role in preventing cancer. People who received recommended daily intake of vitamin D had a low incidence of developing colon, prostate, ovarian, and breast cancers. 
4. Lowers blood sugar: Omega-3 fatty acids in cod liver oil reduce inflammation, control insulin resistance, and help regulate blood sugar levels in the body.
5. Eye health: Vitamin A in cod liver oil protects the surface of the eyes and mucus membranes and slows down the process of age-related macular degeneration and cataract formation, thus preventing vision problems.
6. Bone health: Vitamin D is required for the body to absorb calcium, which is crucial for bone health and protects against osteoporosis (bone loss). Studies have suggested that low vitamin D levels may lead to weak bones and result in an increased risk of hip fractures in older women. Cod liver oil is a good source of vitamin D, so intake of these supplements may help maintain bone health.
7. Rheumatoid arthritis: Omega-3 fatty acids have anti-inflammatory properties that help reduce inflammation and pain associated with rheumatoid arthritis. Vitamin A also helps repair damaged DNA in cells, and vitamin D helps maintain healthy joints.
8. Reduces anxiety: One study reported that omega-3 fatty acids in cod liver oil may reduce depression and anxiety in some people.
9. Improves memory: Studies have suggested that there may be a connection between high concentrations of omega-3 fatty acids and vitamin D and improved cognition and brain function in older people.

Although cod liver oil has shown to have various promising positive outcomes in improving overall health, further studies are needed to confirm these claims.

Cod liver oil is usually considered safe to consume, but too much can  lead to various side effects that include:

1. Risk of bleeding (gum and nose bleeds)
2. Increased risk of hemorrhagic stroke
3. Digestive system symptoms such as flatulence and diarrhea
4. Acid reflux that causes stomach discomfort, nausea and belching
5. Rapid decrease in blood pressure
6. Insomnia (sleeplessness)
7. Risk to the unborn fetus (if consumed during pregnancy)
8. Hypervitaminosis A (vitamin A toxicity), which can cause skin irritation, nausea, dizziness, and joint pain

If you experience any of the aforementioned symptoms, you should reduce or completely stop the consumption of foods and supplements high in omega-3 fatty acids.

Cod liver oil may interfere with other herbal supplements and some medications, especially anti-diabetic drugs, antihypertensive medications, and blood thinners, which may cause serious side effects. You should consult a doctor before using these supplements. 

The FDA does not directly regulate cod liver oil, although it is listed under dietary supplements. It’s best to look for authentic suppliers in order to purchase safe and effective supplements.