Weight loss can have various causes, ranging in severity from 'minor' to 'generally fatal'. Finding the true cause means ruling out or confirming each possibility – in other words, diagnosis.
Diagnosis is usually a complex process due to the sheer number of possible causes and related symptoms. In order to diagnose weight loss, we could:
|Chronic Renal Insufficiency||12%||Unlikely|
|Crohn's Disease||5%||Ruled out|
|Anorexia/Starvation Tendency||1%||Ruled out|
|Lupus (SLE)||0%||Ruled out|
Has your weight decreased significantly for unknown reasons in the past year?
Possible responses:→ Don't know / not applicable
→ No / minimal change
→ 5% to 10% / moderate weight loss
→ 11% to 20% / major weight loss
→ Over 20% / very great weight loss
Weight loss can occur in carcinoid syndrome, as in most cancers, and the presence of diarrhea may contribute to further losses.
Weight loss is a common finding among individuals with chronic heart failure. It is evident that malabsorption of fats is related to heart failure. In one study, subjects with heart disease had 10 times more fat in their stool than heart-healthy individuals. This means those with heart disease weren't absorbing their fats [Am J Cardiology 5: p.295, 1960]. Yet heart patients are typically placed on low-fat diets! These individuals were leaner, but not healthier.
Weight loss can indicate uncontrolled diabetes, while weight gain suggests an increased risk of getting it.