The omega-3 index is inversely associated with the neutrophil-lymphocyte ratio in adults'

Prostaglandins Leukot Essent Fatty Acids. 2022 Feb;177:102397. doi: 10.1016/j.plefa.2022.102397. Epub 2022 Jan 7.


The neutrophil-lymphocyte ratio (NLR) is a biomarker of systemic inflammation and measures innate-adaptive immune system balance. The omega-3-index (O3I) measures the amount of EPA+DHA in blood. Both a low O3I and an elevated NLR are associated with increased risk for chronic disease and mortality, including cardiovascular diseases and cancer. Hypothesizing that low O3I may partly contribute to systemic chronic inflammation, we asked if a relationship existed between O3I and NLR in healthy adults (≥18 y, n = 28,871, 51% female) without inflammation [C-reactive protein (CRP) <3 mg/mL)] who underwent a routine clinical assessment. NLR was inversely associated with O3I before (p < 0.0001) and after adjusting for age, sex, BMI, and CRP (p < 0.0001). Pearson correlations of other variables with NLR were r = 0.06 (CRP), r = 0.14 (age), and r = 0.01(BMI). In this healthy population, an O3I < 6.6% was associated with increasing NLR whereas NLR remained relatively constant (low) when O3I > 6.6%, suggestive of a quiescent, balanced immune system.

Keywords: Docosahexaenoic acid; Eicosapentaenoic acid; Lymphocytes; Neutrophil-lymphocyte ratio; Neutrophils; Omega-3 index.

MeSH terms

  • Adult
  • Docosahexaenoic Acids
  • Eicosapentaenoic Acid*
  • Erythrocytes / metabolism
  • Female
  • Humans
  • Lymphocytes
  • Male
  • Neutrophils*


  • Docosahexaenoic Acids
  • Eicosapentaenoic Acid