Drinking coffee?!

Drinking coffee?

I'm trying to moniter the effects of drinking coffee for a science project, Whenever I drink coffee it always helps me digest my food quicker and even aids weight loss sometimes, it caused sleepless nights occasionly due to the caffine, but the digestion and weight thing really startled me. why is does effects like that occur?

4 months ago
note this was black coffee without milk or sugar etc

Coffee is an appetite suppressant and a diuretic.So you lose weight because you aren't hungry and you are urinating excessively.The weight loss is mostly water weight that you will gain back.Not recommended as a diet plan,causes dehydration.