Cod liver oil is a nutritional supplement derived from liver of cod fish. It has high levels of the omega-3 fatty acids, EPA and DHA, and very high levels of vitamin A and vitamin D. It is widely taken to ease the symptoms of arthritis and for other health benefits. It was once commonly given to children, because the high levels of vitamin D in cod liver oil have been shown to prevent rickets and other symptoms of hypovitaminosis D.

Cod liver oil and fish oil are similar, but cod liver oil has much higher levels of vitamins A and D. Many adults do not meet the RDA for Vitamin D.

^{Depending on the quality of the oil, the flavor and aroma range from a mild sardine-like flavor, to an intense odor of fish and oil. High quality cod liver oil is a pale-yellow, thin, oily liquid, having a slightly fishy and bland taste. Manufacturers sometimes add flavorings, such as citrus or mint essence, to cod liver oil to make it more palatable. While taking the capsules as well as the liquid form, one may experience a rancid fishy aftertaste during belching.}

^{How does cod liver oil improve dental health?}

In the oral cavity, Vitamin A plays a major role in regulating certain functions such as:

-cell differentiation

– wound healing

– tissue regeneration

– maintenance of the integrity of oral mucosa

– keratinization

– resistance to infection

– regulation of taste

– regulation of salivary flow

– tooth development

Deficiency of vitamin A will lead to :

– impaired healing

– desquamation of oral mucosa

– increased risk of infection (eg. oral thrush)

– gum swelling

– increased chance of oral cancer

– loss of taste sensation

– irregular tooth development leading to deformed tooth

– increased risk for dental decay

The high levels of vitamin D content in cod liver oil also helps in improving the strength of the dentition by increasing the calcification and mineralization of tooth structure. It helps in reducing the risk of dental decay, especially in children.

Cod liver oil is widely taken to ease the pain and joint stiffness associated with arthritis, and has also been clinically proven to have a positive effect on heart, bone,as well as helping to nourish skin,hair, and nails. Patients suffering from temporomandibular joint arthritis often have difficulties in opening the mouth, chewing and talking and suffer from pain. These group of people will benefit from consumption of cod liver oil.

Cod liver oil may be an effective complementary measure for long-term treatment of multiple sclerosis. Multiple sclerosis is an inflammatory disease in which the fatty myelin sheaths around the axons of the brain and spinal cord are damaged. MS affects the ability of nerve cells in the brain and spinal cord to communicate with each other. Due to the nerve injury, patient will have speech disorder (dysarthria) and difficulty in swallowing (dysphagia).

Because cod liver oil has a very high level of vitamin A, it is possible to exceed the Recommended Dietary Allowance (RDA) of vitamin A. Vitamin A accumulates in body fat, and can reach harmful levels sufficient to cause hypervitaminosis A. Pregnant women may want to consider consulting a doctor when taking cod liver oil because of the high amount of natural forms of vitamin A such as retinol. High doses of synthetic vitamin A (retinoids) have been shown to cause birth defects.

The risks of hypervitaminosis and of exposure to environmental toxins such as mercury, polychlorinated biphenyls, dioxins, and other contaminants, are reduced when purification processes are applied to produce refined fish-oil products, which consequently contain raised levels of omega-3 fatty acids, such as EPA and DHA.