There are health benefits of cod liver oil and there are drawbacks.
Cod liver oil benefits may not outweigh the risks. The primary benefit
of cod liver oil is related to its omega-3 content, but fish oils
derived from the flesh of fish, rather than the liver, provide that
benefit without the risks.
The health benefits of cod liver oil
are related, primarily to omega-3 fatty acids. These are essential for
the healthy function of the brain, the heart, the joints, the digestive
system and many other systems of the body. Another benefit of cod liver
oil is related to its vitamin E content, which helps the body process
the fatty acids, is an essential antioxidant and promotes the health of
the skin and the hair.
Omega-3 Fatty Acids/Benefits of Cod Liver Oil
Omega-3s
are essential to human health, cannot be produced inside the body, and
so, must be obtained from food or through supplementation. The best
know source of omega-3 fatty acids is fish. Some fish contain more
omega 3s than others.
There are two types of omega-3 fatty acids
that have been identified as essential for human health. They are
Docosahexaenoic Acid or DHA and Eicosapentaenoic Acid or EPA. These are
found primarily in fish. The body can convert another omega-3 fatty
acid, known as Alpha-linolenic acid or ALA, to DHA and EPA, but the
process is relatively inefficient. It is believed that one would have
to consume a great deal of ALA in order to get the health benefits
provided by DHA and EPA.
The omega-3 found in flax seed oil is
ALA. And some believe that flax seed oil can provide cod liver oil
benefits, without the risks, but this is debatable. Although there are
no risks associated with flax seed oil, it is unknown if ALA provides
the same health benefits as DHA and EPA.
The Risks
Cod
liver oil contains large amounts of vitamin A and vitamin D and may
contain contaminants such as mercury and pesticides. The body needs
adequate amounts of vitamin A, but large amounts can be toxic. Vitamin D
is not commonly found in natural foods, but many processed foods are
fortified with vitamin D to ensure good nutrition.
At one time the
benefits of cod liver oil were believed to be associated with its
vitamin A and D content. This was before omega-3 fatty acids had been
identified and before food fortification was a common practice. It was
also before taking daily multi-vitamins became a common practice and
before industrial pollutants had contaminated our oceans.
Vitamin D
While
no tolerable upper limit for vitamin D consumption has been
established, adequate intake for adults, under the age of 50, and
children is believed to be around 200 units per day. Adults over 50
should increase consumption to 400 units per day for men and 600 units
per day for women. Vitamin D is necessary for the body to process
calcium and is therefore a factor in preventing osteoporosis and
maintaining bone health. However, one of the popular cod liver oil
products contains 4000 to 5000 units of vitamin D per teaspoon, more
than anyone needs on a daily basis.
Vitamin A
A
tolerable upper limit for vitamin A has been established. The maximum
amount of vitamin A that a 25 year old man should consumer per day is
10,000 IU. Women should consume less than half that amount. Women who
are pregnant should avoid dietary supplements that contain vitamin A
because of the risk of birth defects. While vitamin A is necessary for
fetal development and overall good health, it is stored in the fat cells
and there is a great risk of over supplementation. Excess consumption
of vitamin A is also believed to contribute to osteoporosis.
One
of the popular cod liver oil products contains 4000-5000 IU of vitamin
A, per teaspoon. When added to the amount that may be present in other
dietary supplements, as well as the food that a person consumes per day,
it will put most people over the safe upper limit for vitamin A. While
the benefit of cod liver oil for supplying essential omega 3s is known,
it is unknown if excess consumption of vitamin A will counteract those
effects.
A better choice for vitamin A supplementation is beta
carotene and other carotenoids. Present in the better daily dietary
supplements, carotenoids are converted by the body to vitamin A on an
as-needed basis and are not associated with the negative effects of
"pre-formed" vitamin A. The only known side effect of excess
consumption of carotenoids is a yellowing of the skin, called
carotenosis, which is not dangerous, but may be undesirable.
Alternatives
Fish
oil derived from the flesh of fish does not contain the vitamins A and
D. Those vitamins are usually present in adequate amounts in daily
multi-vitamins and fortified foods. Though extra vitamin D
supplementation is often recommended for persons over the age of 50, it
is not a benefit of cod liver oil and there are better choices for
vitamin D supplementation.
From an environmental standpoint, over
harvesting of the cod fish has led to the depletion of many populations.
Farms affect the health of wild fish. The equipment used for
harvesting damages the habitat of other water dwelling life forms.
Although there are cod liver oil benefits, these health benefits can be
obtained from other sources that do not cause damage to our environment.By
Patsy Hamilton
