There are lots of blood flow to the stomach after a meal, a drop in blood pressure, brain oxygen and nutrition drops apparently, go to sleep may cause insufficient blood supply to the brain.
还有饭后大量的血液流向胃，血压下降，大脑供氧及营养明显下降，马上入睡会引起大脑供血不足。
2
In traditional Chinese medicine, winter is the best time to nourish the stomach, which is vulnerable to sickness when the temperature drops.