Both are water soluble vitamins and basicall any excess causes you to pee it out. B-6 tends to give me bright yellow pee, which is kinda cool. There are other natural diuretics out there, try a kelp/alfalfa combination or dandelion extract, both work well. Women's sections in chemist's are the best place to find these kind of products as the ladies often use these to combat excess water at that time of the month