We are surrounded by good things to eat in our prosperous society, and the need to carry heavy things, walk long distances, or perform manual labor is greatly reduced. Our bodies take in more energy than they expend, and while the food is easy to eat, it's hard to get rid of. So it's difficult to avoid accumulating fat.
由於富裕社會美食處處，生活中需要負重跋涉或四肢操勞的事又大大減少，在進多出少，而且進來容易出去難的情況下，難怪脂肪會悄悄堆積。