The old wives' tale about chewing everything 20 times might be true - if you did take a bit more time eating, it could have an impact.

老妈妈嚼什么东西都要嚼20次的故事应该是有道理的——如果你稍微多咀嚼一会儿，那么这可能真会对减少肥胖产生有益影响。