Methionine and vitamin B6 intake and risk of pancreatic cancer: a prospective study of Swedish women and men.
OBJECTIVE
It has been hypothesized that dietary factors involved in methyl group metabolism, such as methionine, folate, and vitamin B(6), may modify cancer risk. We have previously reported an inverse association between folate intake and pancreatic cancer risk in a prospective population-based cohort of Swedish women and men. In the present study, we used data from this prospective study to examine whether methionine and vitamin B(6) intakes were associated with the incidence of exocrine pancreatic cancer.


METHODS
Our study population comprised 81,922 Swedish women and men, aged 45-83 years, who were free from cancer and completed a self-administered food-frequency questionnaire in 1997. We used Cox proportional hazards models to estimate rate ratios with 95% confidence intervals (CI), adjusted for age, sex, education, smoking, body mass index, diabetes, and intakes of total energy and dietary folate.


RESULTS
During a mean follow-up of 7.2 years, through June 2005, 147 incident cases of pancreatic cancer were diagnosed. Methionine intake was significantly inversely associated with risk of pancreatic cancer, whereas no significant association was observed for dietary or total vitamin B(6) intake. The multivariate rate ratios comparing the highest with the lowest quartile of methionine intake were 0.44 (95% CI, 0.26-0.73; P for trend = .0005) in women and men combined, 0.59 (95% CI, 0.28-1.21; P for trend = .07) in women, and 0.32 (95% CI, 0.15-0.65; P for trend = .002) in men.


CONCLUSIONS
These findings suggest that higher methionine intake may reduce the risk of pancreatic cancer.
Larsson
Susanna C
SC
Division of Nutritional Epidemiology, National Institute of Environmental Medicine, Karolinska Institutet, SE-17177 Stockholm, Sweden. susanna.larson@ki.se
Giovannucci
Edward
E
Wolk
Alicja
A
D000368:Aged; D000369:Aged, 80 and over; D019587:Dietary Supplements; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D008297:Male; D008715:Methionine / Q000008:administration & dosage*; D008875:Middle Aged; D046790:Pancreas, Exocrine; D010190:Pancreatic Neoplasms / Q000453:epidemiology* / Q000517:prevention & control*; D011446:Prospective Studies; D012307:Risk Factors; D011795:Surveys and Questionnaires; D013548:Sweden / Q000453:epidemiology; D025101:Vitamin B 6 / Q000008:administration & dosage*; D014803:Vitamin B Complex / Q000008:administration & dosage*
D014803:Vitamin B Complex; D025101:Vitamin B 6; D008715:Methionine