Salivation is an extremely intensive process So intense that our salivary glands produce between 0.5 and 1.5 liters of saliva a day. Why? How? Never noticed🤔 All because we reflexively swallow it all the time - otherwise we would have choked on it long ago. But at night it's quite possible, since people can't swallow in their sleep. That's why the body reduces the amount of saliva produced and we can feel dry mouth in the morning.