I bet we all know someone who are trying to lose some weight and yu keep hearing them: i stopped eating bread, i stopped eating this and that. So i am going to explain how this weight game goes from what i have learned so far.
The thing is there is no such thing as a food that makes you gain or lose weight...every food is measured in what is called Calories (actually kilocalories , but we refer them as calorie).
So, the stomach doesent actually know what you feed it ,potatoes, soda,eggs,wine....etc. It just breaks the food down chemically into calories.
Our bodies need a certain amount of calories to keep the organs function , you can use the calculator below to see how many calories you need to maintain your weight based on your age , height and activity level:
http://www.calculator.net/calorie-calculator.html
1 kg or 2.2 pounds of fat is 7500 calories.
For example if you need 2500 calories to maintain your weight and you eat 2800 a day in 25 days you will get 1kg fat...the math is there and its working everytime.
All you need to actually do is count the ammount of calories you put in your mouth and you will convince yourself that this method truly works!
In very simple terms I agree but the makeup of those calories can have vastly different consequences in terms of total health. The body does know and reacts to the type of fuel it is burning. In particular the by products of sugar vs fat digestion is quite different.