How to Gain Weight? - as part of the expert series by GeoBeats. In order to gain weight, you need to add 500 to 1000 calories per day on top of what you are currently doing. Now, it is very important that when your new goal is to gain weight, that you make sure you do it correctly. It is very easy to gain weight eating junk food and eating fast food and not exercising. That is not the kind of weight that you want to gain. That is unhealthy fat weight and it is not good for you. In order to gain healthy weight, you want to make sure you are choosing calorically dense foods, nuts, seeds, avocados, juices. Those are all great ways to add calories to your daily intake and that weight will help you gain weight. Healthy weight gain is half a pound to one pound per week. And again, that helps ensure that you are gaining lean body mass as opposed to fat mass. Exercise and building muscle can also help with the weight gain. And again, it can help keep body fat down as you are increasing calories. Small, frequent meals can also help. Sneaking snacks in, adding liquid calories such as juice or milk, those can also help in gaining weight. If you do exercise, you need to make sure you are fueling your exercise and eating before you exercise, as well as eating after. That way you are not burning too many calories and it does not hinder your weight gain ability.