Dietary self-selection is a fundamental strategy for any foraging insect. Cockroaches such as, Rhyparobia madera, have the ability to choose optimal food sources based on nutritional requirements. Our study focuses on the specific regulation of nutritional preferences based on the concentration of various amino acids in the hemolymph. By injecting individual amino acids into starved cockroaches and recording nutrient selection over a 24 hour period, we were able to distinguish which amino acids play a key role in dietary regulation. To date, we have seen 50% reduction in protein feeding with the injection of the amino acid DL-β-alanine. Further investigation with thin-layer chromatography (TLC) showed this amino acid to be elevated only in those cockroaches which have been fed ad libidum, corroborating the feeding bioassay results. The amino acids that trigger any change in feeding behavior may be active in metabolic pathways, act as precursors to neurotransmitters or regulate hormonal feedback which have a regulatory role in nutrient self-selection.