What’s the secret? The Weight Gain Diet. In this diet, total calorie consumption is more than the body's energy requirements.

If you eat more calories then you spend, the caloric surplus is utilized to build tissue. It can be either fat or muscle tissue. If there are no medical problems, it occurs every time. It is as simple as that.

But your aim should not be to put on just "any weight." It should be healthy weight gain or lean muscle weight gain.

Whether you call it a weight gain diet, muscle building diet, bodybuilding diet, mass building diet, weight training diet, weightlifting diet or simply "get bigger diet," if you aim to add muscle mass you must provide the body with the things it needs to do the job.

What is the quantity of food you should eat?

There are 2 ways to decide how much you must eat to start putting on weight.

The first method is to record your calories for a couple of weeks. Record your whole consumption with the resultant number of calories for this duration and then take the average of the total calories consumed to obtain a daily requirement.

Next, add 300-500 calories to your daily calorie consumption. If you don’t see any improvement after a couple of weeks, add 300-500 calories more. Repeat this till you begin to put on weight.

Another method is to use an elementary bodyweight formula to decide the likely point where you will start gaining: (18-20)(Bodyweight in pounds) = Daily Calorie Consumption

Though the amount of calories consumed will decide if you will or will not put on weight, it is the kind of calories consumed and the time when you consume these calories, that determines if this weight shows up as the muscle or the body fat. Hence begin noting your calories right away.