needless
adjective /ˈniːdləs/
  /ˈniːdləs/
Idioms - (of something bad) not necessary; that could be avoided synonym unnecessary- needless suffering
- Banning smoking would save needless deaths.
- The report caused needless anxiety to hundreds of women.
 Oxford Collocations DictionaryNeedless is used with these nouns:- anxiety
- death
- suffering
- …
 
Idioms 
needless to say 
- used to emphasize that the information you are giving is obvious- The problem, needless to say, is the cost involved.