I'm finding this thread so interesting. The nutritionist from Sloan was the one who recommended the powder from GNC to us. Dave had told her he was using the Carnation 560 to try and keep his calories up (his mouth is too sore to eat much). She recommended trying the powder in addition to the Carnation.

Every Dr we saw urged him to try to keep his calorie intake up. They did stress that it was better if he could do that since he is so thin and many people lose weight with treatment.

I'm going to mention the concerns about GNC mentioned here to get her take on it the next time we speak to her.