The Journal of nutrition
-
The Journal of nutrition · Apr 2000
Circadian variations in plasma and erythrocyte glutamate concentrations in adult men consuming a diet with and without added monosodium glutamate.
This study evaluated the effect of monosodium glutamate (MSG) ingestion as a component of the diet on the 24-h variations in plasma and whole-blood glutamate (GLU) concentrations in healthy adult men. In the first arm of the study, subjects were given test meals without added MSG for 3 d. Protein and energy intakes of the subjects were 1.5 g and 40 kcal/(kg body weight.d), respectively. ⋯ In both trials, plasma GLU concentration increased (P < 0.01) after lunch and dinner, and decreased early in the morning (P < 0.05). Calculated erythrocyte GLU concentrations varied between 500 and 640 micromol/L, with or without MSG addition to the meals. The rather low plasma GLU concentrations over the 24-h period, despite high dietary intake of MSG, indicate that dietary MSG is metabolized very rapidly.