Dietary intake of alpha-linolenic acid and risk of fatal ischemic heart disease among women.
BACKGROUND
Experimental studies in laboratory animals and humans suggest that alpha-linolenic acid (18:3n-3) may reduce the risk of arrhythmia.


OBJECTIVE
The objective was to examine the association between dietary intake of alpha-linolenic acid and risk of fatal ischemic heart disease (IHD).


METHODS
This was a prospective cohort study. The intake of alpha-linolenic acid was derived from a 116-item food-frequency questionnaire completed in 1984 by 76283 women without previously diagnosed cancer or cardiovascular disease.


RESULTS
During 10 y of follow-up, we documented 232 cases of fatal IHD and 597 cases of nonfatal myocardial infarction. After adjustment for age, standard coronary risk factors, and dietary intake of linoleic acid and other nutrients, a higher intake of alpha-linolenic acid was associated with a lower relative risk (RR) of fatal IHD; the RRs from the lowest to highest quintiles were 1.0, 0.99, 0.90, 0.67, and 0.55 (95% CI: 0.32, 0.94; P for trend = 0.01). For nonfatal myocardial infarction there was only a modest, nonsignificant trend toward a reduced risk when extreme quintiles were compared (RR: 0.85; 95% CI: 0.61, 1.19; P for trend = 0.50). A higher intake of oil and vinegar salad dressing, an important source of alpha-linolenic acid, was associated with reduced risk of fatal IHD when women who consumed this food > or =5-6 times/wk were compared with those who rarely consumed this food (RR: 0.46; 95% CI: 0.27, 0.76; P for trend = 0.001).


CONCLUSIONS
This study supports the hypothesis that a higher intake of alpha-linolenic acid is protective against fatal IHD. Higher consumption of foods such as oil-based salad dressing that provide polyunsaturated fats, including alpha-linolenic acid, may reduce the risk of fatal IHD.
Hu
F B
FB
Department of Nutrition, Harvard School of Public Health, Boston, MA 02115, USA. Frank.Hu@channing.harvard.edu
Stampfer
M J
MJ
Manson
J E
JE
Rimm
E B
EB
Wolk
A
A
Colditz
G A
GA
Hennekens
C H
CH
Willett
W C
WC
D000328:Adult; D003327:Coronary Disease / Q000175:diagnosis* / Q000209:etiology / Q000401:mortality; D004042:Dietary Fats, Unsaturated / Q000008:administration & dosage*; D005260:Female; D005518:Food Preferences; D006801:Humans; D008487:Medical History Taking; D008875:Middle Aged; D009726:Nurses; D011446:Prospective Studies; D012306:Risk; D011795:Surveys and Questionnaires; D014810:Vitamin E / Q000008:administration & dosage; D017962:alpha-Linolenic Acid / Q000008:administration & dosage*
D004042:Dietary Fats, Unsaturated; D017962:alpha-Linolenic Acid; D014810:Vitamin E