Abstract It is demonstrated that wheat flour suppresses the activity of inhibitors and increases the dietary efficiency of lentil ( Lens esculenta Moench.) and French bean ( Phaseolus vulgaris L.) for Trogoderma granarium Everts. This antagonism of the inhibitory activity is less marked in green gram ( P. aureus Roxb.) and least in semisynthetic glucose-brewer's yeast mixture. Such inhibition of the antagonistic property of natural foods has not been demonstrated before in insects.