Why is it irresistible?

Why can't people resist food? This is not because we are too greedy, but because of the brain mechanism.

In the process of enjoying delicious food, the brain will secrete dopamine twice at the entrance of food and when it enters the stomach. This mechanism may increase the desire for good food and delay the brain's signal of "satiety". Dopamine is a neurotransmitter, which transmits information of excitement and pleasure, and is a key component of the brain's "reward effect". Dopamine interacts with another substance in the brain-opioid active peptide, which makes people feel happy. If certain behaviors can make the brain secrete dopamine and opioid peptides, the brain will make the body repeat these behaviors. Through positron emission tomography, scientists not only found two peaks of dopamine secretion during eating, but also found specific areas in the brain related to these two peaks: the first secretion occurred in areas related to reward and sensory perception, and the second secretion occurred in areas related to higher cognitive function after food entered the digestive tract. The second dopamine secretion induced by gastrointestinal tract will signal "satiety", while delayed secretion will make people overeat until the second secretion occurs.