Vitamin in one way and another gives protection for a cold (6)
I believe the answer is:
niacin
'vitamin' is the definition.
(niacin is a kind of vitamin)
'in one way and another gives protection for a cold' is the wordplay.
'in one way and another' becomes 'ni in' ('in' reversed and then spelled normally).
'gives protection for' indicates putting letters inside (inserted letters are held or protected).
'a cold' becomes 'ac' (I've seen this in other clues).
'niin' going around 'ac' is 'NIACIN'.
(Other definitions for niacin that I've seen before include "Type of vitamin" , "B vitamin which assists the nervous system" , "Vitamin, nicitinic acid" , "An essential B vitamin in Cain, strangely" , "Another name for nicotinic acid" .)