My older brother has Down syndrome and has unexplained weight loss over the past year. Bloodwork is all fine. He's been drinking Ensure twice a day and that hasn't led to weight gain. He had an incident where he needed an endoscopy to remove food stuck in his esophagus--was thinking that was part of it. But that was over a month ago and his weight is stubbornly the same.

As a scientist (and sister) I find the situation quite frustrating and would like to educate myself on research in this area, but most of what I can find deals with obesity in DS adults. Appreciate any literature those who study DS for a living can share.