Today I learned that..

To lose weight you need to reduce your calorie intake

If you usually need 2500, take about 1800, if you usually need 2000, take about 1500. It doesn't matter what kind of food you eat, as long as you don't eat over or under that new calorie intake. Fruit and Veg are still recommended but do not deprive yourself of eating anything, you need a bit of everything anyway. You could even lose weight by taking in only 1500/1800 cals of junk food a day as did Mark Haub, but it's not advisable. Eat, but eat about a third less calories. That's the big secret.

Source: Mark Haub's Diet