Modern life makes us tired, right? But research from societies in Africa and South America suggests people in the ancient world slept only 6.5 hours a night.

假日期间，很多人经常会熬夜晚睡，觉得反正不用早起上班，晚睡不吃早餐还能减肥，多好的事啊。也有人说，“我一直不吃早餐，体重也没增长，感觉挺好的呀”。人们常说减肥需要“管住嘴，迈开腿”，“少吃，多动”，实在不想动的话少吃也能减肥。确实有不少人希望通过少吃 ...