Brief Answer: So you can start them on your own risk. Detailed Answer: Hello I have studied your case, No one can comment on contents and assurance of Endura mass & Nutrigain Protein powder or, any other weight gain powder. These products may content harmful ingredient which may be toxic to kidney and bone. So you can start them on your own risk. The best way to gain weight is by having a healthy diet. First of all please visit your doctor to look for any medical reasons for being underweight. Then visit a dietician who can plan your diet well as per your need and life style. Do regular exercise about 30-45 minutes in a day on most days of the week along with a protein and calorie rich diet. u have to do running , stretching and small weight exercises that u can learn from going to gym or YOUTUBE also.....do those weight exercises and drink this protein. You do simple but very effective exercises such as push ups, pull ups, dips, free squats etc; these are movements which help put on mass in a beginner. Please do not take any such drugs which promise a miracle including the one you are talking about. There were reports in past about nutrigain powder in some controversy and questions were raised about the safety. Hope this answers your query. If you have additional questions or follow up queries then please do not hesitate in writing to us. I will be happy to answer your queries. Wishing you good health. Take care.

---