[Lani]

there are many causes of unintentional weight loss including (among others):

Gastrointestinal disorders are another common cause of unexplained weight loss – in fact they are the most common non-cancerous cause of idiopathic weight loss. Possible gastrointestinal etiologies of unexplained weight loss are celiac disease, peptic ulcer, inflammatory bowel disease (crohns disease and ulcerative colitis), pancreatitis, gastritis, diarrhea and many other GI conditions can cause weight loss.

Another Cancer, a very common and sometimes fatal cause of unexplained (idiopathic) weight loss. About one-third of unintentional weight loss cases are secondary to malignancy. Cancers to suspect in patients with unexplained weight loss include gastrointestinal, prostate, hepatobillary (hepatocellular carcinoma, pancreatic cancer), ovarian, hematologic or lung malignancies.


Infection. Some infectious diseases can cause weight loss. These include fungal illness, endocarditis, many parasitic diseases, AIDS, and some other sub-acute or occult infections may cause weight loss.

Renal disease. Patients who have uremia often have poor or absent appetite, emesis and nausea. This can cause weight loss.

Cardiac disease. Cardiovascular disease, especially congestive heart failure, may cause unexplained weight loss.

Pulmonary disease.

Connective tissue disease

Neurologic disease, including dementia[*]

In some people, certain medications may cause weight loss as a side effect.

I would think a doctor's job would go be to rule out all other causes of weight loss besides dementia ESPECIALLY weight loss which might be due to other medications she might be taking.

A very likely cause of many problems in the elderly are side effects of drugs they are taking.

Hope this helps.