Comparison of animal and vegetable protein sources in the dietary management of hepatic encephalopathy

Theoretical considerations based on amino acid metabolism in patients with hepatic encephalopathy as well as some limited patient studies had led to the proposal that dietary protein derived from a vegetable source may be better tolerated and more efficacious in such patients. However, studies in normal humans have revealed that vegetable protein is not as nitrogen sparing as animal protein. This prompted us to study under metabolic ward conditions the effects of vegetable and animal protein sources in patients with hepatic encephalopathy with respect to mental status, nitrogen balance, and plasma amino acids. No significant differences regarding any of the parameters studied was observed in relationship to the source of dietary protein, but compliance to the regimen was more difficult with the vegetable protein diet.