Varied food intake, disease, and genetic differences result in complex diet-health interactions. In principle, information-rich metabolic analyses combined with bioinformatic tools provide an approach to explore these interactions. This project is a feasibility study of the use of high-resolution 1H-nuclear magnetic resonance (NMR) to study metabolic perturbations induced by a deficiency in sulfur amino acids (SAA). The investigators will 1) test the hypothesis that deficient dietary intake of SAA in humans results in oxidation of reduced glutathione (GSH)/oxidized glutathione (GSSG) redox and 2) determine whether 1H-NMR of blood and urine detects metabolic changes due to SAA deficiency.