»Basler Zeitung«, 13/04/05

Ancient enzyme as a dietary consultant

The tendency of mammals to eat a balanced diet is inborn, according to a new study. An ancient evolutionary enzyme has been shown to prompt the brain to choose a healthy diet rich in amino acids.

The mechanism was observed by scientists at the New York University School of Medicine. They found the key enzyme in the brain of mice, as reported by the researchers in the April edition of the specialist journal “Cell Metabolism” (Vol. 1, p. 273).

In experiments, the scientists deactivated this enzyme – which resulted in the animals changing their eating habits. The mice no longer cared whether the food was balanced or not. The enzyme triggers a series of electrical impulses that send information to the mouse's brain about the amino acid content of the food, explains David Ron. This way, the brain finds out whether enough amino acids have been absorbed into the blood from the food. If the mouse eats too much “unhealthy” food, the brain sends a message that prompts the mouse to give preference to food with greater amino acid content. The findings of the New York researchers have been corroborated by experiments performed at the University of California: researcher Dorothy Gietzen had already found this enzyme in rats.