For many years we have encountered a repetitious combination of complaints in office practice with children. The familiar list includes poor appetite; failure to gain weight and to grow normally; irritability; frequent gastrointestinal upsets, including vomiting and constipation; repeated bouts of infectious disease; dental caries, and pallor. Frequently when a child has been brought in with one or two of these conditions as presenting symptoms, history and examination have revealed others.
Gradually we came to realize that this combination of complaints is consistently associated with a certain type of dietary history. The child's diet is nearly always adequate in minerals and vitamins but is not adequate in protein. Ordinarily milk and carbohydrate foods are taken in large quantities, but meat, eggs, and other protein foods are neglected. Prompt and dramatic response to provision of adequate protein has established this syndrome, in our minds, as a true deficiency disease.
Lynch HD, Snively WD. HYPOPROTEINOSIS OF CHILDHOOD. JAMA. 1951;147(2):115–119. doi:10.1001/jama.1951.03670190015004