Do doctors see a lot of patients with failure to thrive?

It depends: It depends on which part of the world. Obviously it is a big problem in the developing parts of the world. Most common causes are socioeconomic. In the affluent areas it is more commonly related to gastrointestinal problems (e.g. Reflux, celiac or crohn's disease, cystic fibrosis etc), cleft lip or palate, chronic infections, parasitic infections, milk protein intolerance & rarely metabolic d/s's.

Failure to thrive: We also see patients with failure to thrive amongst our psychiatric population with eating disorders, those who have chronic digestive abnormalities, such as pancreatitis , respiratory disease such as emphysema, and geriatric patients with dementias, and other degenerative diseases.