Dietary polyunsaturated fat intake is associated with low-density lipoprotein size, but not with susceptibility to oxidation in subjects with impaired glucose metabolism and type II diabetes: the Hoorn study.
OBJECTIVE
A high monounsaturated fatty acid (MUFA) and polyunsaturated fatty acid (PUFA) intake is associated with lower plasma low-density lipoprotein (LDL)-cholesterol. However, PUFA may increase the susceptibility of LDL to undergo oxidative modifications. The aim of this study was to analyze the association of habitual dietary fat intake with LDL size and oxidizability.


METHODS
Cross-sectional.


METHODS
Cohort study.


METHODS
Seven hundred and fifty-eight subjects with normal, impaired glucose metabolism and type II diabetes.


METHODS
Mean LDL size was measured by high-performance gel-filtration chromatography. In vitro oxidizability of LDL was determined by measuring lag time, reflecting the resistance of LDL to copper-induced oxidation. Information about dietary fat intake was obtained by a validated food frequency questionnaire.


RESULTS
PUFA intake (energy percent) was significantly and negatively associated with LDL size in subjects with type II diabetes (standardized beta (95% confidence interval) -0.17 (-0.28;-0.06)) and impaired glucose metabolism - although not statistically significant - (-0.09 (-0.24;0.05)), but not in subjects with normal glucose metabolism (0.01 (-0.10;0.12)) (P-value for interaction=0.02). No significant associations were observed for total, saturated fat and MUFA intake with LDL size. Intake of fat was associated with lag time; however, the small magnitude of the associations suggested that the composition of dietary fat is not a major factor affecting lag time. The same association with lag time was observed in all three glucose metabolism categories.


CONCLUSIONS
In individuals with abnormal glucose metabolism, higher PUFA intake is associated with smaller LDL particle size, but does not alter the susceptibility of LDL to in vitro oxidation.


BACKGROUND
Dutch Diabetes Research Foundation, and the Nederlandse Organisatie voor Wetenschappelijk Onderzoek (NWO).
Bos
G
G
Institute for Research in Extramural Medicine, VU University Medical Center, Amsterdam, The Netherlands. griet.bos@rivm.nl
Poortvliet
M C
MC
Scheffer
P G
PG
Dekker
J M
JM
Ocke
M C
MC
Nijpels
G
G
Stehouwer
C D A
CD
Bouter
L M
LM
Teerlink
T
T
Heine
R J
RJ
D000368:Aged; D000369:Aged, 80 and over; D001786:Blood Glucose / Q000378:metabolism; D008078:Cholesterol, LDL / Q000097:blood* / Q000737:chemistry / Q000378:metabolism; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000378:metabolism*; D004042:Dietary Fats, Unsaturated / Q000008:administration & dosage* / Q000378:metabolism; D005231:Fatty Acids, Unsaturated / Q000097:blood / Q000378:metabolism*; D005247:Feeding Behavior; D005260:Female; D018149:Glucose Intolerance / Q000097:blood / Q000378:metabolism*; D006801:Humans; D015227:Lipid Peroxidation; D008297:Male; D008875:Middle Aged; D010084:Oxidation-Reduction; D010316:Particle Size; D011795:Surveys and Questionnaires
D001786:Blood Glucose; D008078:Cholesterol, LDL; D004042:Dietary Fats, Unsaturated; D005231:Fatty Acids, Unsaturated