why is coffee diuretic
For some time there has been a belief that drinking coffee and tea can make you dehydrated because the caffeine they contain has a diuretic effect. (A diuretic is a substance that causes your body to produce urine, and it has been suggested caffeine can do this because it increases blood flow through the kidneys.).or some time there has been a belief that drinking coffee and tea can make you dehydrated because the caffeine they contain has a diuretic effect. (A diuretic is a substance that causes your body to produce urine, and it has been suggested caffeine can do this because it increases blood flow through the kidneys.).