Adherence to the mediterranean diet is inversely associated with circulating interleukin-6 among middle-aged men: a twin study.
BACKGROUND
The Mediterranean diet is protective against cardiovascular disease; a proposed mechanism is through a reduction in systemic inflammation. It is unknown to what extent the association between the Mediterranean diet and inflammation is due to genetic or other familial factors.


RESULTS
We administered the Willett food frequency questionnaire to 345 middle-aged male twins and assessed adherence to the Mediterranean diet using a published adherence score. Fasting plasma levels of interleukin-6, C-reactive protein, and known cardiovascular risk factors were measured. Mixed-effect regression analyses were used to examine the relationship between diet score and inflammatory biomarkers after accounting for known cardiovascular risk factors. Adherence to the Mediterranean diet was associated with reduced levels of interleukin-6 (P<0.001) but not C-reactive protein (P=0.10) after adjustment for total energy intake, other nutritional factors, known cardiovascular risk factors, and use of supplements and medications. When the overall association of adherence to the diet with interleukin-6 levels was partitioned into between- and within-pair effects, the between-pair effect was not significant (P=0.9) and the within-pair effect was highly significant (P<0.0001). A 1-unit within-pair absolute difference in the diet score was associated with a 9% (95% CI, 4.5 to 13.6) lower interleukin-6 level.


CONCLUSIONS
Shared environmental and genetic factors are unlikely to play a major role in the association between adherence to the Mediterranean diet and systemic inflammation. These results support the hypothesis that reduced inflammation is an important mechanism linking Mediterranean diet to reduced cardiovascular risk.
Dai
Jun
J
Nutrition and Health Sciences Program, Emory University School of Medicine, Atlanta, Ga, USA.
Miller
Andrew H
AH
Bremner
J Douglas
JD
Goldberg
Jack
J
Jones
Linda
L
Shallenberger
Lucy
L
Buckham
Rocky
R
Murrah
Nancy V
NV
Veledar
Emir
E
Wilson
Peter W
PW
Vaccarino
Viola
V
D002097:C-Reactive Protein / Q000032:analysis; D002318:Cardiovascular Diseases / Q000517:prevention & control; D038441:Diet, Mediterranean; D006801:Humans; D007249:Inflammation / Q000517:prevention & control; D015850:Interleukin-6 / Q000097:blood*; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D011795:Surveys and Questionnaires
D015850:Interleukin-6; D002097:C-Reactive Protein