Hormones have a lot to do with whether you gain weight or lose weight.
Joseph Strickland, gives us a quick overview in this video.
The glycemic index of the foods you eat can have an effect on insulin.
This is just one example of how what you eat, rather than how much you eat can affect hormones and therefore fat loss or storage.
Weight Loss, Hormones & Diet by Better Body Nutrition Austin
You may want to do more research on the topic of hormones, diet and nutrition.
Learn more about the Glycemic index of foods on Wikipedia. Properly controlling blood sugar with healthy eating habits can help maintain levels of the hormone insulin.