[Effect of monosodium glutamate given orally on appetite control (a new theory for the obesity epidemic)].

Monosodium glutamate is a substance widely used as flavouring agent in the whole world. It is considered to be innocuos by the health agencies of North America and Europe. The effects of the oral administration of two dosages of MSG during the second half of pregnancy and all The developmental process of pups on appetite control and various hormones has been analysed in rats. Effects have been compared with the neonatal parenteral administration of the same compound. The structure of the arcuate nucleus of the hypothalamus has been investigated as well as plasma levels of GH, IGF-1 and leptin and its influence on food consumption. Measurements were performed at 30 and 90 days of life. A nearly total destruction of the arcuate nucleus can be observed with the parenteral administration of MSG but also with the highest oral dose. Significant reductions can be seen in plasma GH and IGF 1 levels at 30 days of life, that are partially recovered at 90 days. Plasma leptin levels are significantly reduced at 90 days of life with the two oral doses together with a significant increase in food intake. In conclussion, oral administration of MSG during pregnancy and development in rats is able to significantly affect hypothalamic control of various hormones and increases appetite.