Read about the effects that junk foods have on health. Feed yourself with it. Then maybe out of fear of that, you may get determined to reduce one by one. Don't do radical changes, that'll hurt and probably won't work. But slow changes are effective. -Start eating less and less junk foods relatively to your past or yesterday. - know why you're doing it and be determined. That's the cost. - you may again lose heart in it but rise up again. It's virtue is greater than the cost and all. Thank you.