system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: smokers should relate to this. Why do we feel the urge to smoke after a meal or while drinking alcohol?

The title is self-descriptive. every smoker should relate to this.
gpt
The urge to smoke after a meal comes from the fact that nicotine stimulates the emission of stomach acid which helps us digest.
As for the smoking while drinking, alcohol blocks the acetylcholine receptors, which are also our nicotine receptors. Thus, the more you drink, the less satisfying a smoke becomes.