I treadmill for 45 mins 6 out of 7 days (covering around 5KM each time) and by the end of it my shirt is covered in sweat. I've been doing this initially doing only 20mins and now over several years I worked up to 45 mins but I haven't been able to lose any weight. Not sure what I'm doing wrong. I avoid fatty food (eg. cheese, deep fried, anything with large amounts of oil).