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(2016·四川高考·D) A warm drink of milk before bed has long been the best choice for those wanting a good night's sleep
But now a study has found it really does help people nod off—if it is milked from a cow at night
Researchers have discovered that “night milk” contains more melatonin (褪黑激素)，which has been proven to help people feel sleepy and reduce anxiety
The study，by researchers from Seoul，South Korea，involved mice being fed with dried milk powder made from cows milked both during the day and at night
Those given night milk，which contained 10 times the amount of melatonin，were less active and less anxious than those fed
