What cause you to use the bathroom to urinate every 20 minutes on some days?

Many possibilities: The most concerning potential causes include bladder or kidney infection, diabetes, or some rare neurological problems. Other causes include things that can cause bladder irritation like sodas, juices, caffeine, vitamins (esp c & b), and concentrated urine from dehydration/inadequate water intake. If concerned please see your doctor. A urine test can help exclude infection or diabetes.