Objective: Intrauterine environmental factors, including maternal diet, may play an etiologic role in acute lymphoblastic leukemia (ALL), a common childhood cancer. Expanding on previous findings from phase 1 of the Northern California Childhood Leukemia Study (NCCLS), a population-based case-control study, we sought to further elucidate and replicate the relationships between maternal diet and ALL risk.
Methods: We matched 282 case-control sets of children (205 pairs and 77 triplets) from phases 1 and 2 of the NCCLS on sex, date of birth, mother's race, Hispanic racial/ethnic status, and county of residence at birth. We used an interviewer-administered food frequency questionnaire to obtain information on maternal dietary intake in the 12 months prior to pregnancy.
Results: Risk of ALL was inversely associated with maternal consumption of vegetable (adjusted odds ratio [AOR] = 0.65, 95% confidence interval [CI] 0.50, 0.84); protein sources (AOR = 0.55, 95% CI 0.32, 0.96); fruit (AOR = 0.81, 95% CI 0.65, 1.00); and legume food groups (AOR = 0.75, 95% CI 0.59, 0.95). The risk reduction was strongest for consumption of the protein sources and vegetable food groups, independent of the child's diet up to age 2 years, and consistent across phases 1 and 2 of data collection for vegetable consumption.
Conclusions: These data suggest that it may be prudent for women to consume a diet rich in vegetables and adequate in protein prior to and during pregnancy as a possible means of reducing childhood ALL risk in their offspring.