Written by Greg Arnold, DC, CSCS. After just 3 hours of exercise, those who supplemented with krill oil for 6 weeks significantly increased immune system protein IL by 45.9% and natural killer immune cells by 6.5%. 

Fish oil’s anti-inflammatory, blood-thinning properties as well as its ability to help regulate heart rhythm make it an ideal supplement for athletes participating in intense exercise (1). Immune system changes that occur after intense exercise can hamper immune system strength and recovery (2).

Now a new study (3) suggests that Krill oil, a type of fish oil, may strengthen the immune system after intense exercise. In the study, 37 subjects (19 men, 18 women) aged 21 to 29 were given either 2,000 milligrams per day of krill oil (18 subjects) or placebo (19 subjects) for 6 weeks. Before and after the study, each subject completed a maximal incremental exercise test and cycling time trial (time to complete set amount of work). Blood samples were collected from the subjects before and after supplementation at rest and then before, immediately after, 1 hour and 3 hours after exercise.

For the cycling test, each subject started at a pace of their choice between 70 and 90 repetitions per minute. They then increased their power by 30 Watts per minute for males and 20 Watts every minute for females until exhaustion.

The researchers found that those in the krill oil group saw 2 significant improvements over the placebo group:

  • A 54.2% increase in the immune system protein IL-2 3 hours post-exercise (875 to 1350 micrograms/mL) compared to an 8.3% increase in the placebo group (900 to 975 micrograms/mL, p < 0.05). Increased activation of IL-2 increases overall immune system strength (4) and may minimize cell damage from exercise.
  • A 17.2% increase in the activity of the immune system cells called Natural Killer cells immediately after exercise (29 to 34) compared to a 10.7% increase in the placebo group (28 to 31) (p < 0.05). As natural killer cells help protect the body against viral infections (5), this increase may help minimize the risk of viral infections during training.

No significant differences were seen between the two groups regarding cycling performance.

For the researchers, “Six weeks of krill oil supplementation can increase IL-2 production and natural killer cell activity 3 hours post-exercise in both healthy young males and females” but that “Krill oil does not modify exercise performance.”

Source:  Da Boit M, Mastalurova I, Brazaite G, McGovern N, Thompson K, Gray SR (2015) The Effect of Krill Oil Supplementation on Exercise Performance and Markers of Immune Function. PLoS ONE 10(9): e0139174. doi:10.1371/journal. pone.0139174

© 2015 Da Boit et al. Creative Commons Attribution License

Click here to read the full text study.

Posted December 21, 2015.

Greg Arnold is a Chiropractic Physician practicing in Hauppauge, NY.  You can contact Dr. Arnold directly by emailing him at PitchingDoc@msn.com or visiting his web site at www.PitchingDoc.com.

References:

  1. Simopoulos AP. Omega-3 fatty acids and athletics. Curr Sports Med Rep. 2007; 6:230-6
  2. Walsh NP, Gleeson M, Shephard RJ, Woods JA, Bishop NC, Fleshner M, et al. Position statement. Part one: Immune function and exercise. Exercise immunology review. 2011; 17:6–63
  3. Da Boit M.  The Effect of Krill Oil Supplementation on Exercise Performance and Markers of Immune Function.  PLoS One. 2015 Sep 25;10(9):e0139174
  4. Balkhi MY. T cell exhaustion and Interleukin 2 downregulation. Cytokine 2015 Feb;71(2):339-47. doi: 10.1016/j.cyto.2014.11.024. Epub 2014 Dec 13
  5. Waggoner SN. Roles of natural killer cells in antiviral immunity. Curr Opin Virol 2015 Nov 16;16:15-23. doi: 10.1016/j.coviro.2015.10.008. [Epub ahead of print]