J Nutr. 2021 Dec 6:nxab412. doi: 10.1093/jn/nxab412. Online ahead of print.
ABSTRACT
BACKGROUND: The relationship between dietary n-3 PUFAs and the prevention of cardiometabolic diseases, including type 2 diabetes, is unresolved. Examination of the association between n-3 PUFAs and chronic low-grade inflammation in a population where many individuals have had an extremely high intake of marine mammals and fish throughout their lifespan may provide important clues regarding the impact of n-3 PUFAs on health.
OBJECTIVE: The aim of this study was to explore associations between concentrations of n-3 PUFAs resulting from habitual intake of natural food sources high in fish and marine mammals with immune biomarkers of metabolic inflammation and parameters of glucose regulation.
DESIGN: A total of 569 Yup’ik Alaska Native adults (18-87 years) were enrolled in this cross-sectional study between December 2016 and November 2019. The red blood cell (RBC) nitrogen isotope ratio (15N/14N, or NIR) was used as a validated measure of n-3 PUFA intake to select 165 participant samples from the first and fourth quartiles of n-3 PUFA intake. Outcomes included 38 pro- and anti-inflammatory cytokines and eight measures of glucose homeostasis associated with type 2 diabetes risk. These outcomes were evaluated for their association with direct measurements of EPA, DHA and arachidonic acid in RBCs.
ANALYSIS: Linear regression was used to detect significant relationships with cytokines and n-3 PUFAs, adiposity, and glucose related variables.
RESULTS: DHA concentration in RBC membranes was inversely associated with IL-6 (β = -0.0066, P < 0.001); EPA was inversely associated with TNFα (β = -0.4925, P < 0.001); and the NIR was inversely associated with MCP-1 (β = -0.8345, P < 0.001) and IL-10 (β = -1.2868, P < 0.001).
CONCLUSIONS: Habitual intake of marine mammals and fish rich in n-3 PUFAs in this study population of Yup’ik Alaska Native adults is associated with reduced systemic inflammation, which may contribute to the low prevalence of diseases in which inflammation plays an important role.
PMID:34871429 | DOI:10.1093/jn/nxab412
