Plasma and erythrocyte amino acid levels in normal adult subjects fed a high protein meal with and without added monosodium glutamate.

It has been suggested that the addition of free glutamate to meals already containing large amounts of protein-bound glutamate would produce an early rapid rise in plasma glutamate and/or aspartate concentrations, increasing the potential for glutamate-induced adverse effects. Normal adult subjects were fed a hamburger and milk shake meal providing protein at 1 g/kg body weight with and without added monosodium L-glutamate (34 mg/kg body weight). The addition of glutamate to the meal at this level had no significant effect on either plasma or erythrocyte concentrations of glutamate or aspartate beyond those arising from the meal itself. Free glutamate added to a hamburger and milk shake meal at this level is rapidly metabolized and does not elevate plasma concentrations of these dicarboxylic amino acids.