Types of Growth Formula, a nutritional supplement for weight gain. Say goodbye to thinness with the Growth Formula nutritional supplement for healthy weight gain, while replenishing the body with the vitamins and minerals it needs. Growth Formula is the most famous nutritional supplement for getting rid of thinness in a short time, in less than a month. It works to increase muscle mass and weight, and gives the body energy and activity. Growth Formula is used to gain weight for children and adults.