Ammonia

Protein intake should be limited to 3 to 6 ounces per meal to avoid overburdening the urea cycle. Ammonia is produced as a byproduct of protein metabolism. The liver converts ammonia to urea via the urea cycle; urea is far less toxic and is excreted by the kidneys. When the liver is damaged, protein is no longer converted to urea and ammonia backs up into the bloodstream and crosses into the brain. Ammonia buildup in the brain is the direct cause of hepatic encephalopathy-like symptoms in aging individuals with liver disease. When the liver is damaged, protein is no longer converted to urea and ammonia accumulates in the bloodstream instead. Ammonia accumulated in the blood crosses into the brain. The liver processes protein into ammonia and then into urea via the urea cycle, with the end product eliminated through urine. The liver converts toxic ammonia, a byproduct of protein metabolism, into urea for excretion. In liver failure, ammonia accumulates systemically rather than being converted to urea and penetrates the brain. Ammonia accumulation is the direct cause of the neurological symptoms in end-stage liver disease. Ammonia has a pH of approximately 11, making it highly alkal…