WeightWatchers is not hard, but it works off of a point system. The formula for the points is a bit arcane [(calories/50) + (fat/12) - (fiber{max of 4}/5)], but the literature has a book of standard stuff with point values, and they have a sliding point calculator for them.
Your number of points per day is based off of a few factors. Your base points is your weight divided by 10 (there is a max allowed for this, but I don't remember it offhand), some many for your age (the younger you are the more you get extra), your sex (men get 8 extra
), and the type of job you do (sedentary jobs get no bonus). When you eat, you keep track of your points.
You get 35 extra points per week that you can use whenever, and you can save points from one day for another, but you have to remain within reason, of course.
There are lots of foods with very low or no points. Some foods are high in points. Basically, you can eat whatever... so long as you count your points. Salad greens are free, as are tomatoes, onions, olives, raw carrots... top it with a fat-free dressing and you have a zero point snack or even a meal. Want to add some chicken? Count the points and away you go. You want cheesecake? Find the point total and count them off, just stay within your limit.
Couple this with some exercise and you are well on your way.