Cod liver oil has been used for centuries for its anti-rachitic properties. We get cod liver oil from codfish (scientific name is Gadus morhua). It is a foul-smelling brown colored liquid. Cod liver oil benefits our health in many ways such as a good source of vitamin A, vitamin D, and omega 3 fatty acids, fights inflammation, good for bones, etc.
Modern science has found even more cod liver oil benefits apart from its antirachitic properties and they are relief from joint pain associated with rheumatic disorders, protective effect on the cardiovascular system, helps in preventing cancer, etc.
What is cod liver oil?
Cod liver oil is a rich source of omega 3 fatty acids, vitamin A, and vitamin D. Omega 3 fatty acids such as Docosahexaenoic acid (DHA) and Eicosapentaenoic acid (EPA) are necessary for brain development and maintaining a healthy lipid profile.
You can get cod liver oil by either eating fresh cod liver or taking supplements. One tablespoon or 4g of cod liver oil contains 4.5g of total fat and 888 mg of Omega-3 fatty acids. (1)
How cod liver oil benefits your health?
1) Loaded with vitamin A
Vitamin A has multiple functions in the human body. It is necessary for night vision. It is essential for maintaining skin in a healthy state.
It has antioxidant properties which protect from free radical-mediated damage. Vitamin A is used as a treatment for certain cancers. It is regularly used in the treatment of acne.
Too much vitamin A is toxic and leads to a condition called hypervitaminosis A. Vitamin A toxicity manifests with raised intracranial tension, nausea, vomiting, and hypercalcemia.
A teaspoonful of cod liver oil is generally safe and does not cause toxicity. A teaspoonful of cod liver oil will provide you with around 90-95% of your daily vitamin A requirements.
2) Provides omega 3 fatty acids
Every cell of your body needs fat to function normally. Cod liver oil provides docosahexaenoic acid and eicosapentaenoic acid. These omega 3 fatty acids found in cod liver oil benefits skin health, help in vitamin and mineral absorption, and boosts immunity.
The ideal ratio of omega 3 to omega 6 fatty acids in your diet is 2:1. Since the advent of processed foods, this ratio is rarely achieved due to the increase in omega 6 and trans fats.
Supplementing your diet with cod liver oil helps you achieve the ideal ratio. They are also helpful in fighting autoimmunity, reducing the risk for cancer, and improving heart health.
3) A treasure trove of vitamin D
Vitamin D deficiency can occur if you don’t don’t get enough sunlight, stay indoors, or live near the poles. Vitamin D is necessary for many essential functions of the body.
It also plays a role in the absorption of calcium from the gut. Vitamin D also boosts the immune system.
Vitamin D deficiency causes rickets in children and osteomalacia in adults. Vitamin D is also a fat-soluble vitamin and is activated in the body.
During the winter season, especially in Canada, Scandinavian countries, sunlight is scarce. In these conditions, cod liver oil serves as a rich source of vitamin D.
Inflammation is a protective response which helps the body to fight off invaders. Unfortunately, if this inflammation continues for a long time, it can cause collateral damage.
An example of chronic inflammation is arthritis, inflammatory bowel disease, etc.
The omega 3 fatty acids present in cod liver oil help to reduce inflammation by down-regulating pro-inflammatory molecules such as IL-1, TNF-alpha, IL-6, etc.(1)
The high vitamin A content helps to reduce inflammatory damage due to free radicals because vitamin A has antioxidant properties. (2)
Studies on the deficiency of vitamin A show that people who are vitamin A deficient are susceptible to inflammation. (3)
5) Provides protect from cardiovascular disease
Heart disease is one of the top causes of mortality and morbidity in both developed and developing nations. The risk factors for heart disease include high triglyceride levels, low HDL cholesterol levels chronic inflammation, high blood pressure, etc.
Evidence-based studies show that omega 3 fatty acids in cod liver oil help to reduce triglycerides. (4) Triglycerides are a significant risk factor for atherosclerosis.
Cod liver oil consumption also reduces blood pressure which is a risk factor by itself for heart disease.
Cod liver oil increases HDL cholesterol levels which protect against plaque formation and reduces the incidence of heart problems.
Hence taking cod liver oil benefits in the reduction of risk factors for cardiovascular disease.
6) Improve the symptoms of anxiety and depression
Anxiety and depression are the most common psychological illness in the world. The lifetime prevalence of depression is estimated to be 17%.
Depression is thought to be due to reduced levels of serotonin, a neurotransmitter, in the brain. Serotonin regulates our mood, appetite, and sleep. Vitamin D binds to receptors in the brain and stimulates a release of serotonin. (5)
There seems to be a link between chronic inflammation and depression. Omega 3 fatty acids help reduce this chronic inflammation and may help improve mood.
A study found people taking cod liver oil showed reduced symptoms of depression and anxiety. (6)
However, further research is required into the effectiveness of cod liver oil when it comes to treating depression and anxiety.
7) Beneficial for pregnant women
Omega 3 fatty acids are required to produce chemicals known as eicosanoids. Eicosanoids have varied functions in the human body.
A deficiency of these chemicals can cause disturbances in various organ systems. Eicosanoids help to initiate and limit inflammation. They are involved in menstrual bleeding and fertility.
DHA(Docosahexaenoic acid), an omega 3 fatty acid found in cod liver oil is required for healthy brain development early in life.
A study among 4-year-olds reports that children born to mothers who consumed cod liver oil during pregnancy had higher intelligence scores than other children. (7)
8) Protects against cancer
Cancer is the unregulated proliferation of immature cells. Vitamin A helps in cell maturation and helps prevent cancer. Vitamin A also acts as an antioxidant and protects our body from free radical damage.
We all know UV ray exposure cause skin cancer. How does this happen? The answer is UV rays damage the DNA by free radical formation.
Hence, cod liver oil with its rich vitamin A content helps to reduce the incidence of cancer. Vitamin A is a treatment for acute myeloid leukemia (M3 subtype).
Studies show the high vitamin D content of cod liver oil is proapoptotic and antiproliferative for mammary tumor cells. (8)
9) Strengthens your bones
Vitamin D found in cod liver oil benefits you in the absorption of calcium from the food. This helps maintain adequate calcium levels in the body and prevent bone resorption.
Thus, it may be a natural remedy for osteoporosis. It also prevents rickets and osteomalacia. Rickets occurs in children, which is a painful condition in which bones of the body are deformed and weak.
Osteomalacia is the term used for adult rickets. Cod liver oil also reduces joint pain and muscle soreness.
10) Improves gastric ulcer healing
Studies conducted in lb settings show cod liver oil benefits in the improvement of gastric ulcer healing rates. The oil has cell-protective effects leading to a reduction in pain caused by gastric ulcers. (9)
Another study conducted on animals shows that cod liver oil suppresses genes linked with gut inflammation. (10)
All these studies are promising, but more evidence is required before recommending cod liver oil as a remedy for gastric ulcers in humans.
11) Improves eye health
Vision loss is a magnanimous health problem, affecting over 300 million people around the world.
Two leading causes of vision loss are glaucoma and age-related macular degeneration (ARMD). Inflammation is associated with ARMD as well as glaucoma. Hence, cod liver oil can help prevent these two diseases. (11)
The high vitamin A content in cod liver oil also helps prevent night blindness. However, high doses of vitamin A are not recommended as it leads to vitamin A toxicity.
12) Maybe helpful in diabetes
Diabetes is characterized by elevated plasma glucose levels and insulin resistance. Dietary supplementation with cod liver oil during pregnancy and the first year of life also reduced the risk of developing diabetes mellitus later in life (12).
Animal studies show regular cod liver oil supplementation reduces inflammatory markers, endothelial damage, and insulin resistance (13).
The oil also helps manage weight gain in rats and reduce markers of metabolic syndrome ( a precursor to diabetes and heart disease).
Still, extensive research in humans is necessary before deciding the effectiveness of cod liver oil in treating diabetes and its related complications.
Adding cod liver oil to your diet
Cod liver oil is widely available in the form of capsules and liquid. Although there are no set guidelines for daily intake, still, recommended intake would be not more than two teaspoons of cod liver oil per day.
Excess cod liver oil can be harmful as it causes vitamin A toxicity. Also, people on blood thinners or blood pressure medication must consult with their doctors before taking cod liver oil as the oil itself has blood thinning effects.
Pregnant women should consult their doctors before taking cod liver oil as vitamin A in excess is teratogenic.
Final words on cod liver oil benefits
The significant cod liver oil benefits are protection against heart disease, a rich source of omega 3 fatty acids, vitamin A and D, Prevents or treats rickets, reduces inflammation, fights ulcers and improves cognitive function.
There are no significant adverse effects to taking a cod liver oil supplement. However, high doses can cause hypervitaminosis A and are not recommended.
An excellent way to consume cod liver oil, mix it with a small quantity of lemon water, applesauce, yogurt or a smoothie to avoid the disagreeable fishy taste. Store your bottle of cod liver oil away from sunlight in a cool, dry place.