In a way, drink helps to make blood! (5)
I believe the answer is:
serum
'blood' is the definition.
(thesaurus)
'in a way drink helps' is the wordplay.
I cannot really see how this works, but
'way' could be 's' (Compass direction - South) and 's' is found within the answer.
'drink' could be 'rum' (rum is a kind of drink) and 'rum' is located in the answer.
A single letter 'e' remains which might be clued in a way I don't see.
This explanation may well be incorrect...
'to make' is the link.
Can you help me to learn more?
(Other definitions for serum that I've seen before include "Antitoxin derived from blood" , "Blood component containing antibodies, used in immunisation" , "Watery part of blood" , "Constituent of blood" , "Watery fluid from animal tissue" .)