The aims of the present study were to assess whether protection against peanut (PN) sensitization can be conferred by maternal PN consumption alone and if so, whether protection was increased by mucosal adjuvant co-administration. Mice were fed with low dose of either PN or PN with cholera toxin (CT) preconceptionally, and during pregnancy and lactation. Offspring serum PN-specific immunoglobulins and cellular responses by splenocytes and mesenteric lymph node (MLN) cells were determined after an active PN sensitization protocol. Milk was collected from lactating mothers of 11-21-day-old pups for evaluation of PN-specific immunoglobulin levels. We found that offspring of PN fed mothers exhibited lower PN-specific IgE levels and reduced PN-stimulated splenocyte and MLN cells cytokine secretion than offspring of non PN fed mothers. CT co-administration with PN enhanced these responses.. Milk from mothers fed PN and CT, but not PN alone preconceptionally and during pregnancy and lactation contained markedly and significantly increased levels of both peanut-specific IgG2a and IgA. Our study demonstrated that maternal feeding of PN alone had a protective effect against PN sensitization of the progeny, which was enhanced by co-administration of a mucosal adjuvant. Increased levels of PN-specific IgG2a and/or IgA in milk were seen when PN and CT were administered together, suggesting that transmission of maternal immunoglobulins may play a role in the observed protection.