According to the Centers for Disease Control and Prevention (CDC), leukemia is the most common childhood cancer, and acute lymphocytic leukemia is the most common type of leukemia. A new study has found that breast feeding for six months may lower the risk of this malignancy. The findings were published in the journal JAMA Pediatrics by researchers at the School of Public Health, University of Haifa, Haifa, Israel; and Ministry of Health, Israel Center for Disease Control, Ramat Gan, Israel.
The study authors note that childhood cancer is a leading cause of mortality among children and teens in developed nations and the incidence increases by 0.9% each year. Leukemia accounts for about 30% of all childhood cancer; however, factors underlying its development remains mostly unknown. Therefore, they conducted meta-analyses of available scientific evidence regarding the relationship between breastfeeding and childhood leukemia. (A meta-analysis is a compilation of data from a number of studies to clarify a point.
The researchers reviewed the medical literature for articles published between January 1960 and December 2014 that investigated the association between breastfeeding and childhood leukemia. For inclusion in the meta-analysis, the studies had to be case control, meaning that they included two groups: breastfeeding and non-breastfeeding. Eligible studies had to describe the months of breastfeeding and had to be published in a peer-reviewed journal with full text available in English.
The investigators identified 25 relevant studies; 18 of them satisfied all inclusion criteria. No bias or disparate factors were found among the eligible studies. The quality of each eligible study was assessed using the Newcastle-Ottawa Scale. The main outcome measurements of the study were no or short duration of breastfeeding and the incidence of childhood leukemia.
The investigators found that their meta-analysis revealed that, compared to no or a short duration of breastfeeding, any breastfeeding for six months or more was associated with a 19% lower risk for childhood leukemia. A separate meta-analysis of 15 studies found that ever breastfed compared with never breastfed was related to a 11% lower risk for childhood leukemia; however, the definition of never breastfed differed between studies. All meta-analyses of subgroups of the 18 studies revealed similar associations. Based on the results of the meta-analyses, 14-19% of all childhood leukemia cases may be prevented by breastfeeding for six months or more.
The authors concluded that breastfeeding is a highly accessible, low-cost public health measure. The meta-analysis that included studies not contained in previous meta-analyses on the subject indicated that promoting breastfeeding for six months or more may help lower childhood leukemia incidence. This benefit is in addition to a number of other reported benefits of breastfeeding.
