Horm Metab Res 2008; 40(3): 199-205
DOI: 10.1055/s-2008-1046759
Humans, Clinical

© Georg Thieme Verlag KG Stuttgart · New York

High Omega-3 Fat Intake Improves Insulin Sensitivity and Reduces CRP and IL6, but does not Affect Other Endocrine Axes in Healthy Older Adults

P. D. Tsitouras 1 , F. Gucciardo 1 , A. D. Salbe 2 , C. Heward 3 , S. M. Harman 1
  • 1Kronos Longevity Research Institute, Phoenix, AZ, USA
  • 2Obesity and Diabetes Clinical Research Section, NIDDK/NIH, Phoenix, AZ, USA
  • 3Kronos Science Laboratories, Phoenix, AZ, USA
Further Information

Publication History

received 04.12.2006

accepted 16.08.2007

Publication Date:
17 March 2008 (online)


Aging diminishes hormone secretion and target cell responsiveness, possibly due to loss of cell membrane fluidity or alteration of membrane phospholipids affecting signal transduction. We investigated whether a high ω-3 polyunsaturated fatty acid diet would improve endocrine function in 6 men and 6 women aged over 60 years. Subjects first ate an isocaloric control diet for 6 weeks, followed by an 8-week experimental diet, which included 720 g of fatty fish weekly plus 15 ml of sardine oil daily. In the last week, we measured RBC membrane fatty acids on each diet, performed pituitary, adrenal, hepatic, and Leydig cell endocrine provocative testing, and assayed selected cytokines. We also assessed insulin sensitivity utilizing octreotide insulin suppression testing and assessed free fatty acid (FFA) responses to isoproteronol. Insulin sensitivity increased significantly after 8 weeks on the ω-3 diet and FFA responses trended lower. Serum C-reactive protein was significantly reduced and a trend towards lower IL-6 was noted. No differences were found in other metabolic parameters, adiponectin levels, or hormone responses. We conclude that, in older people, high ω-3 consumption increases insulin sensitivity, may reduce FFA mobilization by catecholamines, and reduces inflammatory markers, but did not alter endocrine responsiveness after 8 weeks.


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P. D. TsitourasMD 

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