E. Gatti et al., PLASMA AMINO-ACIDS CHANGES IN OBESE PATIENTS ON VERY-LOW-CALORIE DIETS, International journal for vitamin and nutrition research, 64(1), 1994, pp. 81-85
The reduced feeling of hunger alleged by obese patients on very low-ca
lorie diets (VLCD) could be supposed due to restoration to a normal le
vel of plasma TRP:LNAA ratio previously found lowered in these subject
s. We tested this hypothesis measuring weekly the changes of plasma am
ino acid concentration in obese individuals who followed a 5 week slim
ming regimen consisting in a powdered formula diet (500 kcal/d). A dec
rease in plasma TRP:LNAA ratio was seen, since tryptophan decreased, w
hereas valine and isoleucine increased over time. An increase in plasm
a lysine, threonine, glycine and aminobutyrate was also observed The e
arly decrease shown by alanine and glutamate was followed by an increa
se in the last weeks of the study. Our hypothesis was not confirmed, s
ince VLCD failed to carry back the plasma TRP:LNAA ratio to a normal l
evel.