"To place an electronic embedded link to this study in your story Links will be live at the embargo time httparchpedi.jamanetwork.comarticle.aspxdoi.jamapediatrics.. JAMA Pediatrics Breastfeeding for six months or longer was associated with a lower risk of childhood leukemia compared with children who were never breastfed or who were breastfed for a shorter time according to an article published online by JAMA Pediatrics. Leukemia is the most common childhood cancer and accounts for about  percent of all childhood cancers. Still little is known about its cause. Breast milk is meant to exclusively supply all the nutritional needs of infants and current recommendations include exclusively breastfeeding for the first six months of life to optimize growth development and health. Efrat L. Amitay Ph.D. M.P.H. and Lital KeinanBoker M.D. Ph.D. M.P.H. of the University of Haifa Israel reviewed the evidence in  studies on the association between breastfeeding and childhood leukemia. In a review of all  studies the authors found breastfeeding for six months or longer was associated with a  percent lower risk compared with no breastfeeding or breastfeeding for a shorter period of time. A separate analysis of  studies found that ever being breastfed compared with never being breastfed was associated with an  percent lower risk of childhood leukemia. The authors suggest several biological mechanisms of breast milk may explain their results including that breast milk contains many immunologically active components and antiinflammatory defense mechanisms that influence the development of an infants immune system. Because the primary goal of public health is prevention of morbidity health care professionals should be taught the potential health benefits of breastfeeding and given tools to assist mothers with breastfeeding whether themselves or with referrals to others who can help. The many potential preventive health benefits of breastfeeding should also be communicated openly to the general public not only to mothers so breastfeeding can be more socially accepted and facilitated. In addition more highquality studies are needed to clarify the biological mechanisms underlying this association between breastfeeding and lower childhood leukemia morbidity the study concludes. JAMA Pediatr. Published online June  . doi.jamapediatrics... Available preembargo to the media at httpmedia.jamanetwork.com. Editors Note Please see article for additional information including other authors author contributions and affiliations etc."