British Journal of Nutrition

Human and Clinical Nutrition

Fish intake, erythrocyte n-3 fatty acid status and metabolic health in Danish adolescent girls and boys

Lotte Lauritzena1 c1, Laurine B. S. Harsløfa1, Lars I. Hellgrena2, Maiken H. Pedersena1a2, Christian Mølgaarda1 and Kim F. Michaelsena1

a1 Department of Human Nutrition, Faculty of Life Sciences, University of Copenhagen, Frederiksberg, Denmark

a2 Department of Systems Biology, the Technical University of Denmark, Lyngby, Denmark

Abstract

Marine n-3 long-chain PUFA (n-3 LCPUFA) may have a beneficial effect on several aspects of the metabolic syndrome (dyslipidaemia, insulin resistance, hypertension and abdominal obesity). The metabolic syndrome is increasing in prevalence during adolescence, but only few studies have investigated the effects of n-3 LCPUFA in adolescence. The present study examines associations between fish intake (assessed by a 7 d pre-coded food diary), erythrocyte (RBC) DHA status (analysed by GC) and metabolic syndrome measures (anthropometry, blood pressure and plasma lipids, insulin and glucose) in 109 17-year-old children from the Copenhagen Birth Cohort Study. Of the children, 8 % were overweight or obese and few showed signs of the metabolic syndrome, but all the metabolic syndrome variables were correlated. Median fish intake was 10·7 (interquartile range 3·6–21·2) g/d. Boys tended to have a higher fish intake (P = 0·052), but girls had significantly higher RBC levels of DHA (P = 0·001). Sex and fish intake explained 37 % of the variance in RBC-DHA (P < 0·001). After adjusting for confounders, high DHA status was found to be significantly correlated with higher systolic blood pressure (P = 0·014) and increased fasting insulin (P = 0·018), but no adverse association was observed with the mean metabolic syndrome z-score. Overall, the present study showed the expected association between fish intake and RBC-DHA, which in contrast to our expectations tended to be associated with a poorer metabolic profile. Whether these results reflect the physiological function of n-3 LCPUFA, lifestyle factors associated with fish intake in Denmark, or mere chance remains to be investigated.

(Received March 16 2010)

(Revised June 30 2010)

(Accepted July 26 2010)

(Online publication June 07 2011)

Correspondence:

c1 Corresponding author: Dr Lotte Lauritzen, fax +45 3533 2483, email ll@life.ku.dk

Footnotes

Abbreviations: BP, blood pressure; E%, percentage of energy; FA%, percentage of all fatty acids in the chromatogram; HDL-C, HDL-cholesterol; HOMA-IR, homeostasis model assessment of insulin resistance; LCPUFA, long-chain PUFA; RBC, erythrocyte; SBP, systolic blood pressure