Your mouth is on fire, but how do you calm the burn of hot peppers? First of all, you should know what causes the hot pepper to burn: this sensation is due to capsaicin, a molecule present in the membrane that holds together the seeds of the pepper. This molecule irritates cells in the mucus tissue of the mouth in mammals. From a biological perspective, this molecule allows the plant to be less vulnerable to predators. Your mouth is really burning? Contrary to what you may believe, water has no effect on capsaicin so don’t rush to the nearest glass of water. The best response to a pepper that starts to sting is to drink a glass of milk or eat a few spoonfuls of ice cream.