Fish oil - DHA - EPA

Mar 2014   Fish oil with DHA and EPA
Fish oil is extracted from the fatty tissue and the liver of fish. Fish liver oil has been an age old remedy for treating joint pains, rheumatoid arthritis conditions and vitamin A and D deficiency.
With the improved processing technologies the shift has been towards extracting the body oil for its contents of
docosahexaenoic acid (DHA) and
eicosapentaenoic acid (EPA).

The importance of DHA and EPA

ALA, DHA and EPA are very important polyunsaturated omega-3 fatty acids. They are required for many biochemical reactions in the human body. Alpha-linolenic acid (ALA), is an essential omega-3 fatty acid. Our body cannot synthesize ALA and we necessarily have to consume it in our diet. It is available in vegetable oils, flaxseed, rapeseed and soybeans. The long-chain omega-3 fatty acids, DHA and EPA, can be synthesized by the body from ALA but with low efficiency.

DHA and EPA become conditionally essential when ALA cannot be converted due to poor dietary intake, malnutrition, malabsorption or impaired enzyme mechanism. The rich sources of DHA and EPA are fish, krill and microalgae. Many research studies have indicated the importance these omega-3 fats in reducing risks of many inflammatory disorders such as ADHD, cardiovascular diseases and autoimmune diseases.  

Health benefits of DHA and EPA in fish oil

Research studies have indicated an array of health benefits in taking fish oil supplements.
  • Consumption of DHA and EPA has been found to decrease hypertension, decrease platelet aggregation and reduce the risk of arrhythmia and heart attack.
  • EPA reduces the risk of depression, anxiety, aggressive behavior and suicide.
  • Polyunsaturated omega-3 fats improves the brain function leading increased concentration and memory.
  • In persons with hallucinations or delusions, omega-3 fats prevent the onset of schizophrenia.
  • DHA in fish oil is found to be responsible for slowing down the progress of Alzheimer's disease and cognitive problems.
  • The American Heart Association recommends the consumption of 1g of fish oil daily for patients with coronary heart disease.
  • There is a possibility of anti-cancer effects, especially against breast cancer from omega-3 fats.
  • Omega-3 fats have anti-inflammatory function and reduce the risk of inflammatory disorders.
  • Fish oil alleviates the conditions of allergies and psoriasis.
  • Fish oil helps in proper fetal brain development, early visual development, psycho motor development and neurodevelopment.

How do fish get DHA and EPA

Microalgae have the capacity to make the polyunsaturated omega-3 fats. Fish cannot not synthesize the omega-3s. They accumulate the DHA and EPA in their tissues by eating food rich in these omega-3 fats. Smaller fish eat microalgae and accumulate these fatty acids in their tissues. The bigger ones preying on these small fish accumulate higher concentrations in their flesh.

Safety in eating fish

A big draw back in sourcing our requirement of DHA and EPA from fish is the accumulation of toxins in their flesh.
With high level of pollutant discharges into the coastal waters, many marine regions have become polluted with toxic contaminants such as PCBs, mercury, dioxin and chlordane. Fish which are on the higher levels in the food chain, though have higher concentrations of polyunsaturated omega-3 also have high concentration of these toxic contaminants in their tissues. There is a real concern about eating fish and fish oil and the possibility of simultaneously consuming harmful PCBs and methyl mercury.

FDA advisories

FDA had released an advisory about eating fish specifically for women who were pregnant, were planning a pregnancy or were nursing a baby. They were advised against eating shark, swordfish, king mackerel, or tilefish for their high mercury content. However FDA recommended eating safer fish like canned light tuna catfish, pollock, salmon and shrimp for their protein and omega-3 values. FDA also recommended checking local advisories for local catches from lakes and waterways.

Side effects and dangers

The side effects may include nausea, bloating, flatulence, belching and diarrhea.
As DHA and EPA in fish oil have blood thinning effects, taking it along with blood-thinning medications can cause serious bleeding.
Those taking blood-thinning medications such as aspirin, warfarin or clopidogrel must take fish oil only under the supervision of their physician.

Fish oil with DHA and EPA is unstable unless antioxidative protection is present. It can turn rancid and spoil. Peroxides are formed during spoilage affecting gastrointestinal tract. The concentration of the polyunsaturated omega-3s and their ratio may vary from brand to brand depending upon the methods of processing. Some fish oils may not contained the amount of DHA and EPA as claimed on the label. Proper institutional regularization is the need of the day.

Related posts in nutritional deficiency diseases:
Definition of saturated fatty acids.
Definition of unsaturated fatty acids.
Examples of unsaturated fatty acids.
Definition of trans fatty acids.
Examples of monounsaturated fatty acids.
Structure of polyunsaturated fatty acids.
Two essential fatty acids.
Arachidonic acid foods.
DHA from algae.
Krill EPA.

Current topic in nutritional deficiency diseases:
DHA and EPA in fish oil

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