title: Nutrients related to one-carbon metabolism and risk of renal cell cancer.
abstract: OBJECTIVE
  Folate, vitamins B6 and B12, methionine, choline, and betaine are nutrients related to one-carbon metabolism and have been hypothesized to decrease cancer risk. Few studies have evaluated dietary intakes of these nutrients in relation to renal cell cancer (RCC).
  
  
  METHODS
  We conducted prospective follow-up studies of women in the Nurses' Health Study and men in the Health Professionals Follow-up Study. Diet was assessed repeatedly using a validated semi-quantitative food-frequency questionnaire in both studies.
  
  
  RESULTS
  During follow-up of 24 years among 77,208 women (918,891 person-years) and 22 years among 47,886 men (1,731,752 person-years), we accrued 436 cases of RCC (225 women and 211 men). Intakes of folate, vitamins B6 and B12, methionine, and betaine were not found to be related to RCC risk. Higher intake of free choline, but not other forms of choline, was associated with reduced RCC risk. The results were similar in men and women.
  
  
  CONCLUSIONS
  We found little evidence that higher intakes of nutrients related to one-carbon metabolism lower RCC risk. One-carbon metabolism may have little influence on renal carcinogenesis.
authors.affiliation: Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA. hpeyc@channing.harvard.edu
authors.forename: Eunyoung
authors.initials: E
authors.lastname: Cho
authors.forename: Edward L
authors.initials: EL
authors.lastname: Giovannucci
authors.forename: Hee-Kyung
authors.initials: HK
authors.lastname: Joh
mesh_terms: D000328:Adult; D002244:Carbon / Q000378:metabolism*; D002292:Carcinoma, Renal Cell / Q000453:epidemiology* / Q000378:metabolism / Q000517:prevention & control; D004032:Diet; D005260:Female; D005492:Folic Acid / Q000008:administration & dosage; D006801:Humans; D015994:Incidence; D007680:Kidney Neoplasms / Q000453:epidemiology* / Q000378:metabolism / Q000517:prevention & control; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012307:Risk Factors; D014481:United States / Q000453:epidemiology; D014805:Vitamin B 12 / Q000008:administration & dosage; D025101:Vitamin B 6 / Q000008:administration & dosage
chemical_list: D002244:Carbon; D025101:Vitamin B 6; D005492:Folic Acid; D014805:Vitamin B 12