Oily fish reduces plasma triacylglycerols: a primary prevention study in overweight men and women.
OBJECTIVE
Previous studies have demonstrated benefits of high-dose long-chain omega-3 polyunsaturated fatty acid (LC omega-3 PUFA) supplements on metabolic risk. Effects of increased dietary omega-3 PUFA, via oily fish and/or plant-derived omega-3 PUFAs, are less clear and may be modulated by the omega-6:omega-3 PUFA of the habitual diet. This study examined the effect on cardiovascular disease risk markers of reducing dietary omega-6:omega-3 PUFA by changes in linoleic acid:alpha-linolenic acid (LA:LNA) and/or increasing LC omega-3 PUFA. It tested whether decreases in LA:LNA modulate effects of LC omega-3 PUFA.


METHODS
One hundred forty-two subjects, recruited to a 24-wk randomized study, were assigned to a control group or one of four interventions. Intervention groups received two portions of oily fish (4.5 g eicosapentaenoic acid + docosahexanoic acid) or white fish (0.7 g eicosapentaenoic acid + docosahexanoic acid) per week, and replaced habitual household fats with ones high in sunflower (high LA:LNA) or rapeseed (low LA:LNA) oil.


RESULTS
Modest dietary manipulations of omega-6 and omega-3 PUFAs resulted in significant group x time interactions for serum triacylglycerols (TAGs; P = 0.05); at 24 wk the control and two oily fish groups showed lower TAG than did the white fish/sunflower group (P = 0.05). Reductions in TAG, associated with increased oily fish intakes, were maximized when combined with lower dietary LA:LNA. There were no significant changes in several other cardiovascular disease risk markers.


CONCLUSIONS
Two portions of oily fish per week led to significant reductions in TAG relative to consumption of two portions of white fish per week. Changes in TAG were maximized when combined with lower LA:LNA.
Moore
Carmel S
CS
Medical Research Council Human Nutrition Research, Elsie Widdowson Laboratory, Cambridge, UK. carmel.moore@mrc-hnr.cam.ac.uk
Bryant
Susan P
SP
Mishra
Gita D
GD
Krebs
Jeremy D
JD
Browning
Lucy M
LM
Miller
George J
GJ
Jebb
Susan A
SA
D015415:Biomarkers / Q000097:blood; D002318:Cardiovascular Diseases / Q000097:blood / Q000517:prevention & control*; D004042:Dietary Fats, Unsaturated / Q000008:administration & dosage*; D005229:Fatty Acids, Monounsaturated; D015525:Fatty Acids, Omega-3 / Q000008:administration & dosage; D043371:Fatty Acids, Omega-6 / Q000008:administration & dosage; D005260:Female; D005395:Fish Oils / Q000008:administration & dosage / Q000737:chemistry; D006801:Humans; D019787:Linoleic Acid / Q000008:administration & dosage; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000097:blood*; D010938:Plant Oils; D000074262:Rapeseed Oil; D012307:Risk Factors; D000074242:Sunflower Oil; D014280:Triglycerides / Q000097:blood*; D017962:alpha-Linolenic Acid / Q000008:administration & dosage
D015415:Biomarkers; D004042:Dietary Fats, Unsaturated; D005229:Fatty Acids, Monounsaturated; D015525:Fatty Acids, Omega-3; D043371:Fatty Acids, Omega-6; D005395:Fish Oils; D010938:Plant Oils; D000074262:Rapeseed Oil; D000074242:Sunflower Oil; D014280:Triglycerides; D017962:alpha-Linolenic Acid; D019787:Linoleic Acid