After an upset, has us taking food, but it's disgusting (10)
I believe the answer is:
nauseating
'it's disgusting' is the definition.
(nauseating is a kind of disgusting)
'after an upset has us taking food' is the wordplay.
'after' means one lot of letters go next to another.
'upset' is a reversal indicator.
'has' says to put letters next to each other.
'taking food' becomes 'eating' (I've seen this before).
'an' in reverse letter order is 'na'.
'na'+'us'='naus'
'naus' next to 'eating' is 'NAUSEATING'.
'but' acts as a link.
(Other definitions for nauseating that I've seen before include "Stomach-turning" , "Loathsome" , "arousing unpleasant feeling" , "Revolting" , "being hard to keep down" .)