Excess eating of fried foods can cause some troubles. Particularly fried starchy foods cause more harm on prolonged intake.  They are difficult to digest and gets deposited as fat in body thus causing obesity which is known as a causative factor for many health troubles. Reused oils and oils with less smoking point, when heated beyond point cause release of free radicals which are carcinogenic. Occasionally having fried food, using fresh oils with high smoking point for deep frying,  good physical exercises, adequate water intake minimises the effects caused by fried foods to some extent. Hope the information provided is helpful to you.