title: Influence of a healthy Nordic diet on serum fatty acid composition and associations with blood lipoproteins - results from the NORDIET study.
abstract: BACKGROUND
  The fatty acid (FA) composition of serum lipids is related to the quality of dietary fat intake.
  
  
  OBJECTIVE
  To investigate the effects of a healthy Nordic diet (ND) on the FA composition of serum cholesterol esters (CE-FA) and assess the associations between changes in the serum CE-FA composition and blood lipoproteins during a controlled dietary intervention.
  
  
  METHODS
  The NORDIET trial was a 6-week randomised, controlled, parallel-group dietary intervention study that included 86 adults (53±8 years) with elevated low-density lipoprotein cholesterol (LDL-C). Serum CE-FA composition was measured using gas chromatography. Diet history interviews were conducted, and daily intake was assessed using checklists.
  
  
  RESULTS
  Food and nutrient intake data indicated that there was a reduction in the intake of fat from dairy and meat products and an increase in the consumption of fatty fish with the ND. The levels of saturated fatty acids in cholesterol esters (CE-SFA) 14:0, 15:0, and 18:0, but not 16:0, showed a significant decrease after intake of ND compared to the control diet (p<0.01). Also, a significant increase in serum 22:6n - 3 was observed compared with the control diet (p<0.01). The changes in CE-SFA 14:0, 15:0, and 18:0 correlated positively with changes in LDL-C, HDL-C, LDL-C/HDL-C, ApoA1, and ApoB (p<0.01), respectively, whereas the changes in polyunsaturated fatty acids in cholesterol esters (CE-PUFA) 22:6n - 3 were negatively correlated with changes in the corresponding serum lipids.
  
  
  CONCLUSIONS
  The decreased intake of saturated fat and increased intake of n-3 PUFA in a healthy ND is partly reflected by changes in the serum CE-FA composition, which are associated with an improved serum lipoprotein pattern.
authors.affiliation: Department of Public Health and Caring Sciences, Clinical Nutrition and Metabolism, Uppsala University, Uppsala, Sweden.
authors.forename: Viola
authors.initials: V
authors.lastname: Adamsson
authors.affiliation: Department of Public Health and Caring Sciences, Clinical Nutrition and Metabolism, Uppsala University, Uppsala, Sweden.
authors.forename: Tommy
authors.initials: T
authors.lastname: Cederholm
authors.affiliation: Department of Public Health and Caring Sciences, Clinical Nutrition and Metabolism, Uppsala University, Uppsala, Sweden.
authors.forename: Bengt
authors.initials: B
authors.lastname: Vessby
authors.affiliation: Department of Public Health and Caring Sciences, Clinical Nutrition and Metabolism, Uppsala University, Uppsala, Sweden; ulf.riserus@pubcare.uu.se.
authors.forename: Ulf
authors.initials: U
authors.lastname: Risérus
keywords: n-3 polyunsaturated fatty acids; plasma cholesterol; saturated fat; serum cholesterol esters; stearoyl-CoA desaturase-1