My sources are medical books that I have and that you can get anywhere and also doctors that I personally know. Any medical book will tell you the effects on pills have on each other. Certain pills when combine and taken over a course of years will make your body retain water. It actually will build up in your body and it more dangerous than being fat. Yes, getting fat is a problem and will cause certain problems. But with retaining water in your body will causes more serious problems like liver problems, colon problems, heart problems, stomach problems and many more. Jak when retaining water it will also make you gain weight as well.