If milk and cookies are the order of the day, I'll pack 3 chocolate chip cookies, a total of 180-200 calories. I'll also drink skim milk instead of higher fat content milk like 1%, 2% or whole milk. Don't count out the fruit either. A nice apple can be a real treat, especially this time of year. Soon, oranges will be in season, another alternative or supplement to a controlled snack. Also realize that exercise is a great way to blow off steam and diffuse stress. I can't think of a better antidote to stress or weight gain than a regular exercise program. If none of these work for you, see your doctor. You may need some simple tests to make sure nothing is wrong with your metabolism.