Creatine and phosphocreatine serve not only as an intracellular buffer for adenosine
triphosphate, but also as an energy shuttle for the movement of high-energy phosphates
from mitochondrial sites of production to cytoplasmic sites of utilization. The spontaneous
loss of creatine and of phosphocreatine to creatinine requires that creatine be continuously
replaced; this occurs by a combination of diet and endogenous synthesis. Vegetarians
obtain almost no dietary creatine. Creatine synthesis makes major demands on the�…