Hello Autumn Rose I had gone through your question very diligently and I can understand your concern mucle loss could be related to various factors like genetics like high catabolism environmental factors poor nutrition Indigestion or mal absorption Infection or worm infestation metabolic disorder or hormonal imbalances i would like further information to help you better like had she recently lost any weight? I would advise you certain life style modifications and adoption of healthy food habits Have plenty of fresh fruits and vegetables Avoid spicy fried and junk food or carbonated drinks Have good amount of protein in your diet like egg, meat, fish and beans (dal) Have glass of milk during breakfast and supper sprouted grains and nuts , soybeans are good source of protein Have lots of water and fruit juices exercise regularly like gymming cycling and swimming as far as protein supplements are concerned I am not in favour of it as it contains fortified protein supplements which may cause constipation, flatulence and stomach discomfort I would suggest you to follow above mentioned guidelines genuinely, you will definitely get healthy weight there are various homeopathic and ayurvedic medicines are there which increases appetite and subsequently weight increases. Hope you will find my response helpful and informative please feel free to ask for more clarification good luck