The survey, carried out by a market research company for Pantene, was conducted last month.
It also asked women what they believed could torture their hair the most - bleaching or the overuse of hot styling tools.
Forty-one per cent said the bleach bottle was the lethal weapon, while 26 per cent of women said repeated use of heated styling tools had the most potential to wreck hair.
Shoreh Barkhordari, a senior stylist at Rodney Wayne Albany, said older women who came to their salon tended to have healthier hair than some young women.
"It depends on hair type and style. The young people tend to use straighteners more often - they like their hair straight all the time.
"When the fashions and the colours change, we get a lot of people who come in to dye their hair constantly. That's not necessarily bad, but we do give them advice."
Another stylist, Aucklander Joy Mati, said times had changed and teenage girls and young women were more aware about taking care of their locks.
However, those who religiously used hot irons and straighteners should be warned.
"If they don't know what happens now, they'll find out soon. [Constant use] will wreck their hair," she said.
"It can dry out your hair and strip it of nutrients. It slowly singes your hair. ... The hair, from scalp down to mid-length, will look healthy. But the tips will look dry."
HAIR TORTURE
* 48 per cent of Kiwi women use hot styling tools once a week.
* 13 per cent use hot styling tools daily or more frequently.
* 8 per cent use hot styling tools once a month.
WORST CELEBS
* 36 per cent Lady Gaga
* 14 per cent Rihanna
* 9 per cent Britney Spears
* 8 per cent Katy Perry.