Why are you in a bad mood on rainy days?

The reason why weather conditions affect a person's emotional state is because there is a substance called pineal gland in the human body.

The pineal gland is very sensitive to sunlight. When the sun is full, it will be greatly inhibited, while the concentration of exciting hormones such as thyroxine and adrenaline will increase relatively, and people will be more excited and active.

On the contrary, if it rains continuously and the sun is not seen, the number of pineal glands will increase obviously, the concentration of hormones that stimulate people will decrease relatively, and people will become listless.