Krill oil omega-3 fatty acids - Krill DHA - Krill EPA

Mar 2014   Omega-3 DHA and EPA in krill oil
Krill, small shrimp-like crustaceans, are very important food sources of many marine animals including the largest known animal species, the blue whale.
Krill is a rich source of omega-3 (n-3) long-chain polyunsaturated fatty acids (PUFAs), such as
eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA).

Omega-3 fats like, alpha-linolenic acid (ALA), EPA and docosahexaenoic acid are very important for the biological functions of the human body. In the recent years, the role of PUFA nutrition in stress-resilience, neurodevelopment and neurocognition has been recognised. Recent research studies have associated the risk of diseases such as inflammation, neurodegenerative disorders and neuropsychiatric disorders with the nutritional deficiency of EPA and docosahexaenoic acid.

Omega fats -ALA, EPA and DHA

ALA is available from plant based foods like vegetable fats, walnuts and algae. EPA and DHA are present in marine sources of food such as fish, algae and krill. However ALA form of omega-3 is not directly used by the body and it has to be metabolized into EPA and DHA for the utilization of the body. ALA is not well-absorbed in the intestines and vegans have the risk of developing nutritional deficiency diseases of omega-3 fats. Though ALA supplementation appears to increase the EPA, there is not much increase in docosahexaenoic acid in phospholipids. Administration of preformed docosahexaenoic acid shows significant increase in its proportion in phospholipids.

What is krill oil?

Krill is shrimp-like crustacean thriving in oceans forming swarms. The body of this crustacean contains lipids in the form of oil. Though there are more than eighty species of krill, the most sought after species are Antarctic krill, Euphausia superba. Antarctic krill has higher concentrations of omega-3 EPA, docosahexaenoic acid and astaxanthin antioxidant.

The nutritional value of krill increases with the Antarctic summer with increased availability of their food, phytoplankton. The right harvesting time will be at the end of an Antarctic summer. Soon after the harvest, the krill are quick-frozen to preserve their nutritional value. Two extraction methods, namely hexane extraction and cold-vacuum extraction process are used for the extraction of krill oil. In hexane extraction, small quantities of the chemical may remain back in the end product. In cold-vacuum extraction process, the nutrients are not affected and no additives are present.

Bioavailability of krill DHA and EPA

Compared to fish fats, docosahexaenoic acid content of the krill oil is similar, but the EPA content of fish oil is higher. In fish, the fats are stored as triglycerides. However, in krill oil about 50% of the FAs are attached to phospholipids, especially phosphatidylcholine. Research studies have indicated that omega-3 fats as phospholipids are better absorbed than those from triglycerides. Bioavailability of docosahexaenoic acid in the plasma and its concentration in the target cell membranes increased substantially when ingested as phospholipids.

Stine M. Ulven et all in their comparative study of krill oil and fish fats found that when "the daily EPA + DHA dose in the krill oil group was 62.8% of the dosage given in the fish oil group", "Plasma levels of EPA, docosahexaenoic acid, and DPA increased significantly from baseline to the end of the intervention phase" but there was no significant difference in the change of omega-3 fats between the fish fats and the krill oil groups. It was concluded that omega-3 fats from krill oil are readily and effectively absorbed after ingestion and subsequently distributed in the blood.

Health benefits of krill oil

  • It contains omega-3 EPA and DHA in phospholipid structure which increases the absorbability.
  • Though a marine source, the risk of contamination with heavy metals is minimal.
  • It is also a natural source of vitamins A, D and E.
  • The potent antioxidant, astaxanthin, present in krill oil increases the shelf-life of the product.
  • Many antioxidant benefits are realized from the krill lipids.
  • Omega-3 fats like EPA have shown immense benefits in hypertension, cardiovascular diseases and coronary heart disease.
  • Omega-3 docosahexaenoic acid and EPA generate neuroprotective metabolites alleviating the conditions of ADHD, dyslexia, autism, schizophrenia, personality disorder, bipolar disorder, cognitive impairment, cognitive decline and psychosis.
  • Omega-3 fats, docosahexaenoic acid and EPA are required for the neurodevelopment of the fetus and for treating maternal depression.
  • Omega-3 fats docosahexaenoic acid and eicosapentaenoic acid are effective in treating inflammation and pain due rheumatoid arthritis.
Omega-3 krill oil has few side effects. Rarely some people may suffer from belching, nausea, bloating, or diarrhea. People using hypertension medication, diabetes medication, anticoagulants, weight loss medicines must consult their health care provider before using krill lipid supplements as they may be contraindicated.
Related topics on Nutritional deficiency diseases:
DHA and pregnancy.
DHA and brain.
Omega 3 fatty acids food sources
DHA food sources.
DHA side effects.
Algal DHA.
DHA fish oil.
DHA supplements.
Arachidonic acid (ARA).

1.Stine M. Ulven, Bente Kirkhus, Amandine Lamglait, Samar Basu, Elisabeth Elind, Trond Haider, Kjetil Berge, Hogne Vik,  Jan I. Pedersen. Metabolic Effects of Krill Oil are Essentially Similar to Those of Fish Oil but at Lower Dose of EPA and DHA, in Healthy Volunteers. Lipids. 2011 January; 46(1): 37–46.
2.Joanne Bradbury. Docosahexaenoic Acid (DHA): An Ancient Nutrient for the Modern Human Brain. Nutrients. 2011 May; 3(5): 529–554.

Current topic in Nutritional deficiency diseases:
omega-3 krill oil - Krill DHA and EPA

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