Effect of varying the ratio of n-6 to n-3 fatty acids by increasing the dietary intake of alpha-linolenic acid, eicosapentaenoic and docosahexaenoic acid, or both on fibrinogen and clotting factors VII and XII in persons aged 45-70 y: the OPTILIP study.
BACKGROUND
Elevated fibrinogen, activated factor XII (FXIIa), and factor VII coagulant activity (FVIIc) are associated with higher risk of fatal ischemic heart disease. This study tested the hypothesis that lowering the dietary ratio of n-6 to n-3 polyunsaturated fatty acids (n-6:n-3) would modify these risk factors in older men and women.


OBJECTIVE
The objective of the study was to measure fasting hemostatic risk factors and postprandial changes in activated FVII (FVIIa) concentrations after a 6-mo alteration in dietary n-6:n-3.


METHODS
In a randomized, parallel design in 258 subjects aged 45-70 y, we compared 4 diets providing 6% of energy as polyunsaturated fatty acids at an n-6:n-3 between 5:1 and 3:1 with a control diet that had an n-6:n-3 of 10:1. The diets were enriched in alpha-linolenic acid, eicosapentaenoic (EPA) and docosahexaenoic (DHA) acid, or both.


RESULTS
Fasting and 3-h plasma triacylglycerol concentrations were 11.1% and 7.2% lower with the diet that had an n-6:n-3 of approximately 3:1 and that was enriched with EPA and DHA than with the other diets. Fasting fibrinogen, FXIIa, FVIIc, FVIIa, and FVII antigen and postprandial FVIIa were not influenced by the diets. Avoiding foods high in fat the day before measurement decreased FVIIc and FVIIa by 8% and 19.2%, respectively. A test meal containing 50 g fat resulted in a mean 47% (95% CI: 42%, 52%) increase in FVIIa 6 h later, but the response did not differ by n-6:n-3.


CONCLUSIONS
Decreasing the n-6:n-3 to approximately 3:1 by increasing the intake of EPA and DHA lowers fasting and postprandial plasma triacylglycerol concentrations in older persons but does not influence hemostatic risk factors.
Sanders
Thomas A B
TA
Nutritional Sciences Research Division, King's College London, London, United Kingdom. tom.sanders@kcl.ac.uk
Lewis
Fiona
F
Slaughter
Suzanne
S
Griffin
Bruce A
BA
Griffin
Margaret
M
Davies
Ian
I
Millward
D Joe
DJ
Cooper
Jackie A
JA
Miller
George J
GJ
D000368:Aged; D019540:Area Under Curve; D004042:Dietary Fats, Unsaturated / Q000008:administration & dosage / Q000097:blood; D004281:Docosahexaenoic Acids / Q000008:administration & dosage / Q000097:blood; D015118:Eicosapentaenoic Acid / Q000008:administration & dosage / Q000097:blood; D005167:Factor VII / Q000032:analysis*; D015956:Factor XIIa / Q000032:analysis*; D005215:Fasting / Q000097:blood; D015525:Fatty Acids, Omega-3 / Q000008:administration & dosage* / Q000097:blood; D043371:Fatty Acids, Omega-6 / Q000008:administration & dosage* / Q000097:blood; D005260:Female; D005340:Fibrinogen / Q000032:analysis*; D006487:Hemostasis / Q000187:drug effects; D006801:Humans; D008297:Male; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000097:blood / Q000453:epidemiology; D019518:Postprandial Period; D012307:Risk Factors; D014280:Triglycerides / Q000097:blood*; D017962:alpha-Linolenic Acid / Q000008:administration & dosage / Q000097:blood
D004042:Dietary Fats, Unsaturated; D015525:Fatty Acids, Omega-3; D043371:Fatty Acids, Omega-6; D014280:Triglycerides; D017962:alpha-Linolenic Acid; D004281:Docosahexaenoic Acids; D005167:Factor VII; D005340:Fibrinogen; D015118:Eicosapentaenoic Acid; D015956:Factor XIIa