A method of producing bee larvae that are at least 100% greater in weight than control larvae comprising feeding young worker bees a histone deacetylase (HDAC) inhibitor or a mixture of HDAC inhibitors and feeding bee larvae royal jelly secreted by these young worker bees, while the bee larvae of the control receive the royal jelly produced by young worker bees not fed with a HDAC inhibitor or a mixture of HDAC inhibitors, wherein the HDAC inhibitor is selected from the group consisting of suberoylanilide hydroxamide acid (SAHA), Taiwanese green propolis, propolin A, propolin B, propolin C, propolin D, propolin E, propolin F, propolin G, propolin H, propolin I, propolin J, and