We usually recommend gaining weight to people who consistently weigh too little, which can cause a range of health problems. Bodybuilders and other athletes may also hope to gain weight by building muscle. We have some weight gaining programs to help you to keep your weight balanced. While obesity is becoming a significant public health risk, being underweight can also cause health problems. However, there are still many misunderstandings about the correct methods for putting on weight safely. Some methods of gaining weight can have severe short- and long-term effects on health. This poses a challenge for people needing to gain weight and for those who are at a healthy weight but wish to build muscle. This article provides tips for gaining weight safely and healthily, including what to avoid while trying to put on weight.