Dietically, it helps in raising the sugar level (6)
I believe the answer is:
raisin
'sugar level' is the definition.
The definition and answer can be both things that one consumes for nourishment as well as being singular nouns.
Perhaps you can see a link between them that I don't see?
'dietically it helps in raising' is the wordplay.
I cannot quite understand how this works, but
'in' is found in the answer.
This may be the basis of the clue (or it may be nonsense).
'the' is the link.
Can you help me to learn more?
(Other definitions for raisin that I've seen before include "Large dried grape" , "Cultivating" , "A dried grape, nice in cake" , "Dried red grape" , "Dried grape used in cakes" .)