It is believed that the organs of severely malnourished children malfunction because harmful compounds called oxidants injure the tissues in these organs. In a healthy person oxidants are made harmless because another compound called glutathione neutralizes them. Glutathione is made from three amino acids that we get from the protein we eat in our food. We found that malnourished children were not making enough glutathione because they lacked one of these amino acids called cysteine. In this study we determine why malnourished children do not have sufficient cysteine, and we will feed malnourished children a whey-based diet which is rich in cysteine during their treatment to determine whether they will make more glutathione. This in turn may make their organs recover faster. These findings will let us know whether malnourished children can recover faster if they are given more cysteine during the early phase of treatment.