People ask me almost daily what is the best diet out there. I say simple science. The only way to lose weight has to do with the simple principal of calories in vs calories out. This means to lose weight you need to consume less calories than you expend. THIS DOES NOT MEAN MAJOR CALORIE RESTRICTION. You need to know how many calories your body needs to function and then figure out how many calories your body needs depending on your activity level. You can take this number and subtract no more than 500 calories a day and you will see your weight drop.
It is important to understand that if you consume anything in excess, ANYTHING, it will be converted into fat. ANYTHING means healthy food too.
You may have heard of the twinkie diet where Mark Haub spent 10 weeks eating sugary foods like little debbies, oreos, sugary cereal, etc every 3 hours and lost 27 lbs. The trick was that he limited his daily calorie intake to 1800 calories. He is a nutrition professor and new the amount of calories his body needed for weight loss. He proved that it really all comes down to consuming less calories than he expended.
Now not all calories are alike. I would NEVER recommend such a ludicrous meal plan. Your body needs fuel and powering it with sugar is not the answer. If you eat a 100 calorie snack pack of oreos, I guarantee you will be hungry shortly after. If you eat 100 calories of a fiber packed food like almonds, fruit or whole grains, you will be full longer. Plus you will gain the nutritional benefits that the empty calorie foods cannot provide you.