高普考/三四等/高員級◆英文題庫下載題庫

        Animal studies confirm that the relief some of us get from eating sugar is not just psychological—it is an actual brain-chemistry reaction. In one experiment, Blass and colleagues studied two groups of baby mice who were separated from their mothers and left alone for six minutes. Their resulting “isolation distress” was considered to be a kind of animal equivalent to our human version of depression. The depressed mice who were given sugar water cried only seventy-five times during their isolation—as compared to the more than three hundred cries that came from the mice left 

alone with no sweet treat to alleviate their emotional pain. Apparently, the young mice were literally “medicating” their depression with sugar. 

        Why did sugar have this remarkable effect? Researchers thought that perhaps the sweet food stimulated the release of extra beta-endorphin molecules. Since these molecules help us cope with physical and emotional pain, the sugar had a literally soothing effect. Researchers confirmed their theory by giving both groups of mice Naltrexone, a drug that blocks beta-endorphin receptors. If you take Naltrexone, it does not matter how many beta-endorphins you release—you will not get any relief from pain. Sure enough, when the sugar-fed mice were given Naltrexone, they lost all interest in the sweet substance, suggesting that their only reason for their sweet tooth had been to stimulate the release of beta-endorphins. 

        Numbed by Naltrexone, both groups of mice cried equally often. The poor baby mice were still depressed—but now even sugar could not make them feel better.