Krill Oil Clinical Evidence

Lipids

Journal of Evidence-Based Complementary & Alternative Medicine Takanari, J., et al. Effects of

Ulven SM, et al. Metabolic effects of krill oil are essentially similar to those of fish oil but at lower dose of EPA and DHA, in healthy volunteers. 2011 Jan;46(1):37-46.

Topic: 
Does the molecular form of omega-3 influence its affect on plasma levels of EPA and DHA? 

Background:
Both krill oil and fish oil contain omega-3 fatty acids; however in krill oil it is present in phospholipid form, while in fish oil it is present in triacylglycerol form. Does the form impact its absorption?

Study Type:
Human clinical intervention trial

Study Design:                                                                                                                                                                                                                    Randomized, placebo-controlled. Subjects were divided into three groups and took krill oil, fish oil, or nothing for 7 weeks. Researchers measured subjects’ plasma levels of EPA, DHA, and DPA.

Subjects:
113 subjects with normal or slightly elevated total blood cholesterol and/or triglyceride levels

Dosage: 
3 grams of krill oil (providing 543 mg of omega-3) or 1.8 grams of fish oil (providing 864 mg of omega-3)

Results:
Both groups supplemented with omega-3 fatty acids experienced significant increases in plasma EPA, DHA, and DPA compared with controls; however, there was not a significant difference in changes in any of the omega-3s between the fish oil and krill oil groups. 

Conclusion:
“Krill oil and fish oil thus represent comparable dietary sources of n-3 PUFAs, even if the EPA + DHA dose in the krill oil was 62.8% of that in the fish oil.”

 

Journal of the American College of Nutrition

Deutsch L. Evaluation of the effect of Neptune Krill Oil on chronic inflammation and arthritic symptoms. 2007 Feb;26(1):39-48.

Topic: 
What effect does Neptune Krill Oil (NKO) have on C-reactive protein (CRP) in patients with chronic inflammation, and how effective is NKO on symptoms of arthritis?

Background:
Omega-3 fatty acids are well-established to have anti-inflammatory properties. CRP is a standard test for assessing systemic inflammation levels.

Study Type:
Human clinical intervention trial

Study Design:                                                                                                                                                                                                                    Randomized, double-blind placebo-controlled. Subjects took either NKO or a placebo daily. Their CRP levels and scores on two assessments of osteoarthritis were measured at the beginning of the study and after 7, 14, and 30 days of supplementation.

Subjects:
90 subjects with a confirmed diagnosis of cardiovascular disease and/or rheumatoid arthritis and/or osteoarthritis, who also had elevated CRP levels.       
Dosage: 
300 mg of NKO for 30 days                                                                                                                                                                                                                   
Results:
Supplementation with NKO decreased CRP levels significantly compared to placebo at 14 and 30 days:

NKO
7 days: decreased CRP by 19.3%, pain by 28.9%, stiffness by 20.3%, and functional impairment by 22.8%
14 and 30 days: further decreased CRP by 29.7% and 30.9% respectively

Placebo
7 days: decreased CRP by 15.7%
14 days: increased CRP by 32.1%
30 days: decreased CRP by 25.1%

Conclusion:                                                                                                                                                                                                                                      “The results of the present study clearly indicate that NKO at a daily dose of 300 mg significantly inhibits inflammation and reduces arthritic symptoms within a short treatment period of 7 and 14 days.”

 

Poster Presentation, Montreal Neurological Hospital and Institute.

Rouder L. Evaluation of the effects of Neptune Krill Oil adult attention deficit and hyperactivity. 

Topic: 
Is Neptune Krill Oil (NKO) safe and effective for the treatment of adult ADHD?

Background:
Omega-3 fatty acids are well-established to have anti-inflammatory properties. CRP is a standard test for assessing systemic inflammation levels.

Study Type:
Human clinical intervention trial

Study Design:                                                                                                                                                                                                                       Prospective open label study. Subjects took NKO for 24 weeks. They were tested at the beginning of the study, as well as at 12 and 24 weeks, for executive function, behavioral inhibition, and self control.

Subjects:
30 subjects with a mean age of 23 years who had had a diagnosis of ADHD for an average of 7 years                                                                                        
Dosage: 
500 mg of NKO for 24 weeks                                                                                                                                                                                                          
Results:
NKO improved several major executive brain functions after 24 weeks, including 60.2% for concentration, 48.8% for focus and 47.8% for planning skills.

Conclusion:                                                                                                                                                                                                                                     “NKO® may be considered a safe, toxic free treatment able to improve brain executive function for adults having ADHD. This may act to reduce the need for stimulant medication, reducing treatment costs and improving the life quality of patients.”

Mechanism of Action:                                                                                                                                                                                                    Krill oil provides Omega-3 PUFAs, and increases plasma EPA, DHA, and DPA comparable to fish oil, even though the EPA + DHA dose is only 62.8% of that in fish oil. Omega-3 fatty acids in krill oil are bound to phospholipids, which make them more easily absorbed by virtue of the water-soluble phosphate portion. Phospholipids are also more readily incorporated into cell membranes, which are composed of phospholipids. Because omega-3s support optimal cell membrane structure and cell function, they have a range of physiological roles, and they play a role in preventing, and possibly even treating, a broad range of health conditions.

Nutrition Research

Saldeen T, Wallin R, Marklinder I. Effect of a small dose of stable fish oil substituted for margarine in bread on plasma phospholipid fatty acids and serum triglycerides. 1998;18:1483-1492.


Topic: 
Can a small amount of fish oil, substituted for margarine in the diet, have a sizeable impact on blood lipids?

Background:
Fish oil has been shown to help reduce several risk factors for cardiovascular disease. However, because it is fatty by nature, adding fish oil to the diet necessarily increases the amount of fat consumed. What if margarine were replaced with fish oil?

Study Type:
Human clinical intervention trial. A small dose of fish oil was substituted for margarine on bread. Blood levels of phospholipid fatty acids and triglycerides were measured at baseline and after 4 weeks

Study Design:                                                                                                                                                                                                                      Randomized, parallel, single-blinded.

Subjects:
17 healthy subjects                                                                                                                                                                                                                                              
Dosage: 
1 gram of fish oil containing 38% omega-3 fatty acids                                                                                                                                                                                                                              
Results:
4 weeks of fortification with fish oil increased blood levels of phospholipid fatty acids by almost 50% and decreased triglycerides by 17%. Fish oil intake did not affect lipid peroxidation or blood sugar levels. 

Conclusion:                                                                                                                                                                                                                                      “This study showed that by use of a stable fish oil preparation it is possible to substitute fish oil for margarine in bread, a food product consumed in large amounts, and that a small amount of this fish oil has significant effects on blood lipids, without any signs of lipid peroxidation.”

Sports Medicine, Training and Rehabilitation

Baker SJ, Al-Najadah R. Effect of ingesting fish oil on serum lipid and lipoprotein concentration in exercising and nonexercising women. 1996;6(4):287-297.                                                                                                                                                                                                                                       
Topic: 
How do fish oil, fish oil plus exercise, or exercise only affect blood lipids in pre and postmenopausal women?

Background:
Elevated blood lipids are considered a risk factor for cardiovascular disease. Does fish oil have an effect on blood lipid levels?.

Study Type:
Human clinical intervention trial. Women were randomly divided into three groups: fish oil, fish oil plus exercise, or exercise only for 12 weeks. A control group followed their normal routine for the duration of the study period. Blood lipids were measured at baseline and at four intervals of 1 week in all subjects. Body fatness was also measured.

Study Design:                                                                                                                                                                                                                      Randomized, controlled

Subjects:
30 premenopausal and 30 postmenopausal women                                                                                                                                                                                      
Dosage: 
1 fish oil capsule daily, containing 171 mg EPA and 114 mg DHA                                                                                                                                                                                                   
Results:
Both the fish oil and fish oil plus exercise groups experienced a decrease in LDL. There were no changes in triglycerides. Both groups that exercised experienced decreases in body fat.

Nutrition Research

Liu M, Wallin R, Saldeen T. Effect of bread containing stable fish oil on plasma phospholipid fatty acids, triglycerides, HDL-cholesterol, and malondialdehyde in subjects with hyperlipidemia. 2001 Nov;21(11):1403-1410.

Topic: 
What is the effect of ingesting a small amount of fish oil daily through enriched bread?

Background:
Some evidence has shown that fish oil supplementation can positively affect blood lipids. Will it be effective at a low dose?

Study Type:
Human clinical intervention trial. Subjects were randomly divided into three groups: stable fish oil with oat fiber, control with oat fiber, and control with wheat fiber. Phospholipid fatty acids, triglycerides, HDL-cholesterol, and malondialdehyde (a marker of lipid peroxidation) were measured at baseline, as well as after 2 and 4 weeks of supplementation.

Study Design:                                                                                                                                                                                                                    Randomized, controlled.

Subjects:
36 subjects with hyperlipidemia (elevated blood lipids)                                                                                                                                                                             
Dosage: 
1.3 grams of stable fish oil                                                                                                                                                                                                                                                                              
Results:
Subjects consuming fish oil experienced increases in blood levels of EPA and DHA at 2 and 4 weeks. They also had decreased triglycerides and increased HDL cholesterol. There were no significant changes in either of the control groups. Fish oil did not induce lipid peroxidation. 

Conclusion:                                                                                                                                                                                                                                      “This study showed that in subjects with hyperlipidemia intake of bread containing a small amount of fish oil results in a significant increase in omega-3 fatty acids, an increase in HDL-cholesterol, and a decrease in triglycerides and MDA, which may reduce the risk of ischemic heart disease.”

 

Pediatric Research

Birch EE, et al. Visual acuity and the essentiality of docosahexaenoic acid and arachidonic acid in the diet of term infants. 1998 Aug;44(2):201-9.         
Topic: 
Are docosahexaenoic acid (DHA) and arachidonic acid (AA) necessary for brain and eye development?

Background:
The brain and eye — particularly the retina — contain high levels of omega-3 fatty acids. They accumulate in these tissues during late pregnancy and in early infanthood. What role do they play in brain and eye development? 

Study Type:
Human clinical intervention trial. 

Study Design:                                                                                                                                                                                                                             Double-blind, randomized: 79 infants were formula-fed from birth and 29 were breast-fed. The infants were evaluated four times over their first 12 months of life for blood fatty acid composition, growth, sweep visual evoked potential (VEP) acuity, and forced choice preferential looking acuity. 

Subjects:
108 healthy term infants                                                                                                                                                                                                                                          
Dosage: 
Formula supplemented with DHA (0.35% of total fatty acids) or with DHA (0.36%) and AA (0.72%)                                                                                                                                                                                                                              
Results:
4 Infants who were supplemented with DHA or DHA + AA had total red blood cell lipid composition and sweep VEP acuity comparable to that of breast-fed infants, while infants who were not supplemented did not.

Conclusion:                                                                                                                                                                                                                                     “Early dietary intake of preformed DHA and AA appears necessary for optimal development of the brain and eye of the human infant.”

Investigative Ophthalmology & Visual Science

Malcolm CA, et al. Scotopic electroretinogram in term infants born of mothers supplemented with docosahexaenoic acid during pregnancy. 2003 Aug;44(8):3685-91.                                                                                                                                                                                                                                                                                                   
Topic: 
Does supplementing pregnant women with fish oil rich in DHA enhance retinal development in healthy term infants?

Background:
Several studies in both preterm and term infants indicate that omega-3 fatty acids may be necessary for healthy visual development. Can this be proven? 

Study Type:
Human clinical intervention trial. 

Study Design:                                                                                                                                                                                                                    Randomized, placebo-controlled. Subjects were divided into two groups: half received a fish oil supplement, while half received placebo of oleic acid. Both groups took their assigned pills from 15 weeks until delivery. Total fatty acids in mothers’ red blood cells and plasma were measured at baseline, 28 weeks, and delivery, and in infants at delivery. Within the first week of life, infants’ retinal development was also assessed

Subjects:
100 pregnant women                                                                                                                                                                                                                                                   
Dosage:                                                                                                                                                                                                                                                                          
Results:
DHA levels of infants did not differ between groups. However, there was a correlation between infant DHA status and retinal maturity at birth, regardless of which group they were in. In fact, infants in the highest quartile for umbilical cord blood DHA had higher retinal sensitivity compared with those in the lowest quartile. Additionally, infants in the highest quartile for plasma DHA were more likely to be carried to term than those in the lower quartiles.

Conclusion:                                                                                                                                                                                                                                      “These findings demonstrate an association between the DHA status of term infants and retinal sensitivity, suggesting an essential role of this long-chain polyunsaturated fatty acid (LCPUFA) in the development and function of the retina.”