Indigestion from fatty foods can have various causes, just like most other symptoms. 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 indigestion from fatty foods, we could:
Is your stomach upset by fatty/oily/fried food?
Possible responses:→ No / only if the serving is too large / don't know
→ Occasional slight indigestion after fatty food
→ Frequent slight indigestion / sometimes severe
→ Frequent severe indigestion
→ I can't tolerate fatty/oily/fried foods at all