Hi, Although endura mass claimed to be useful and an easy way to gain and maintain weight, however its efficacy and safety has not been proved on any clinical study. It is a protein supplement and as the name suggests which should be taken only if your diet is insufficient in supplying enough proteins. It consists of soy proteins, skimmed milk, sucrose, minerals & vitamins. It does not contain steroids. It is well tolerated by most of the users however it can cause a few of possible side-effects on prolonged use like hormone imbalance, fatty liver, loss or libido, increase in blood sugar and cholesterol, thinning of the bones, and indigestion.In view of the above I would advise you to take a balance diet rich in high class proteins such as meat, fish, eggs, fresh fruits & vegetables. Also do regular exercise as it stimulates your appetite and take plenty of oral fluids. Hope I have answered your query. Let me know if I can assist you further. Regards, Dr. Mohammed Taher Ali, General & Family Physician