title: Low-fat diet and skin cancer risk: the women's health initiative randomized controlled dietary modification trial.
abstract: BACKGROUND
  Large cohort studies have reported no relationship between dietary fat and nonmelanoma skin cancer (NMSC), although a low-fat diet intervention reduced NMSC risk in a small clinical trial. In animal studies, skin tumor development has been reduced by low-fat diet. We evaluated the effect of a low-fat dietary pattern on NMSC and melanoma in the Women's Health Initiative Dietary Modification trial.
  
  
  METHODS
  Postmenopausal women aged 50 to 79 years (n = 48,835) were randomly assigned to the low-fat dietary pattern intervention (n = 19,541) or comparison group (n = 29,294). The intervention goals included decreasing fat intake to 20% or less of calories, increasing vegetable and fruit intake, and increasing grain intake. Self-reported incident NMSC (n = 4,907) and physician-adjudicated incident melanoma (n = 279) were ascertained every 6 months.
  
  
  RESULTS
  Over 8.1 years of follow-up, the low-fat diet intervention did not affect overall incidence of NMSC [HR 0.98; 95% confidence interval (CI), 0.92-1.04] or melanoma (HR, 1.04; 95% CI, 0.82-1.32). In subgroup analyses of melanoma risk, baseline fat intake interacted significantly with group assignment (Pinteraction = 0.006). Among women with higher baseline fat intake, the dietary intervention significantly increased risk (HR, 1.48; 95% CI, 1.06-2.07), whereas, among women with lower baseline fat intake, the intervention tended to reduce melanoma risk (HR, 0.72; 95% CI, 0.50-1.02).
  
  
  CONCLUSIONS
  In this large randomized trial, a low-fat dietary pattern did not affect overall incidence of NMSC or melanoma.
  
  
  CONCLUSIONS
  A low-fat diet does not reduce incidence of NMSC, but an interaction between baseline fat intake and dietary intervention on melanoma risk warrants further investigation.
authors.affiliation: Stanford School of Medicine, Stanford University, Stanford, USA.
authors.forename: Christina S
authors.initials: CS
authors.lastname: Gamba
authors.forename: Marcia L
authors.initials: ML
authors.lastname: Stefanick
authors.forename: James M
authors.initials: JM
authors.lastname: Shikany
authors.forename: Joseph
authors.initials: J
authors.lastname: Larson
authors.forename: Eleni
authors.initials: E
authors.lastname: Linos
authors.forename: Stacy T
authors.initials: ST
authors.lastname: Sims
authors.forename: James
authors.initials: J
authors.lastname: Marshall
authors.forename: Linda
authors.initials: L
authors.lastname: Van Horn
authors.forename: Nathalie
authors.initials: N
authors.lastname: Zeitouni
authors.forename: Jean Y
authors.initials: JY
authors.lastname: Tang
mesh_terms: D000368:Aged; D015331:Cohort Studies; D018752:Diet, Fat-Restricted / Q000706:statistics & numerical data*; D004041:Dietary Fats / Q000008:administration & dosage*; D005247:Feeding Behavior; D005260:Female; D006801:Humans; D015994:Incidence; D008875:Middle Aged; D017698:Postmenopause / Q000378:metabolism; D012307:Risk Factors; D012878:Skin Neoplasms / Q000453:epidemiology*; D016896:Treatment Outcome
chemical_list: D004041:Dietary Fats