Childhood folate, B6, B12, and food group intake and the risk of childhood brain tumors: results from an Australian case-control study.

ABSTRACT

PURPOSE: The etiology of childhood brain tumors (CBT) is poorly understood, but dietary factors could be involved. In this case-control study of CBT, the possible associations of childhood intake of dietary and supplemental folate, vitamin B6, and vitamin B12 with the risk of CBT were investigated, along with various food groups. METHODS: Cases diagnosed between 2005 and 2010 were identified from 10 pediatric oncology centers in Australia and controls by nationwide random-digit dialling. For study children of ages 3-14 years, diet in the year before diagnosis (or recruitment) was assessed using food frequency questionnaires. Folate intake was adjusted for bioavailability, and dietary micronutrient intake was energy-adjusted. Micronutrients and food groups were analyzed using logistic regression adjusting for relevant confounders. Principal components analysis was conducted to assess food group intake patterns for analysis. RESULTS: Food and micronutrient data were available for 216 cases and 523 controls. Folate intake was associated with a reduced risk of CBT overall (odds ratio for highest tertile vs. lowest 0.63, 95% confidence interval 0.41, 0.97) and particularly low-grade gliomas (odds ratio for highest tertile vs. lowest 0.52, 95% confidence interval 0.29, 0.92). Vitamin B6 and B12 intake was not associated with CBT risk, nor was processed meat. CONCLUSIONS: High folate intake during childhood may reduce the risk of CBT. This potentially important finding needs to be corroborated in other studies. If replicated, these results could have important implications for public health recommendations regarding diet during childhood.