A low-protein diet is prescribed for those with inherited metabolic disorders, such as Phenylketonuria and Homocystinuria and reduced protein levels have been used by people with kidney or liver disease. Low protein consumption appears to reduce the risk of bone breakage, presumably through changes in calcium homeostasis.[1] Consequently, there is no uniform definition of what constitutes low-protein, because the amount and composition of protein for an individual suffering from phenylketonuria would differ substantially from one suffering homocystinuria or tyrosinemia[2]. The amount used by those with liver disease would still result in individuals being in nitrogen balance.