You have probably seen many famous fitness models sharing their eating plans on the internet that consist of 6-8 meals throughout their day. I love the expressions of surprise on the faces of the people whom I advise to eat about 6 times a day. Most of the times their reactions are: "You do know I am trying to lose weight, not gain weight, right?". For many it is confusing - you eat more to lose more, but how ?
Well again, it's common sense. Your body's metabolism needs to be maintained at higher rates in order to boost your weight loss. And how is your metabolic rate elevated? That's right, eating!
Every time you consume a macronutrient be it carbohydrate, protein or fat, your body's metabolic rate goes up because it is using energy to digest those foods. This is why complex carbohydrates (carbs coming from foods rich of fiber) are your prime choice. By maintaining an elevated metabolic rate you are literally burning body fat as you are just sitting around and eating.
But it's not just your metabolic rate. By consuming more meals you are properly spreading your macronutrients throughout your day. See, if you eat only 2 or 3 times you are putting too much on your plate at once - your body needs time to digest foods and those that it cannot digest in a fixed amount of time it will store as body fat so it can use it later as a secondary source of energy.
By eating 5-7 times a day you allow your body to have enough time to properly digest all of the nutrients and for all of the nutrients to come into use and NOT get stored as body fat.