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A new study has found that redheads are more than twice as likely to avoid a visit to the dentist - possibly because they are more sensitive to pain. But does hair colour really mean more discomfort in the dentist chair?
Does this hurt more than usual?
Nicole Kidman, Hazel Blears and Prince Harry may all share ginger coloured locks, but could they also share a fear of the dentist? Some scientists say yes.
Perhaps no-one enjoys the prospect of the dentist's drill or a shot of novocaine, but new findings published in the Journal of the American Dental Association suggest that the problem may be a bit more serious for redheads.
The research, conducted by the Cleveland Clinic in Cleveland, Ohio, comes a few years after other studies found that people with red hair are typically more sensitive to pain and more resistant to anaesthesia - and require about 20% more of it to be effective.
This new study measured the anxiety that redheads feel about the dentist and concluded that they are not only nervous, but are more than twice as likely to avoid a visit altogether compared with their brunette and blonde counterparts.
US studies suggest redheads require more anaesthesia
But researchers in the UK and Canada say people with ginger hair are the same or more pain-tolerant
The researchers recommended that dentists proceed gingerly, so to speak, by evaluating all patients - especially redheads - for anxiety.
So is it true? Some scientists aren't yet convinced, citing studies that suggest the exact opposite - maybe redheads are actually more stoic.
"Careful work has been done to suggest that redheads may well have a reduced sensitivity to pain," says Ian Jackson, head of medical and developmental genetics at the Medical Research Council in Edinburgh. "They respond to analgesics [painkillers] better than non-redheads."
Red locks are usually caused by a mutation in a gene called MC1R, which produces the substance that gives hair, skin and eyes their colour. Some studies have indicated that this mutation may also affect the way pain is felt. But scientists don't necessarily agree on how it works.
A few years ago, Canadian researcher Jeffery Mogil published findings that people with red hair may actually have a higher tolerance for pain and require less anaesthesia during surgical intervention.
And so far, Mr Jackson's research has pointed in a similar direction.
Using mice with the mutated redhead gene - which actually turns them yellow, not ginger - he found that male "redheads" had the same pain tolerance as non-redheads. And the female redhead mice actually had an increased tolerance for heat pain and a decreased tolerance for cold pain.
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"You stand the mouse on iced water and you see how it moves its feet," he says of the technique.
While this study hasn't yet translated to humans, Mr Jackson says the comparison would be similar to the pain felt while washing dishes in hot water. And, according to his findings, ginger-haired women may be able to handle the higher temperatures.
So what happens when different scientists produce entirely different results? More testing, says Mr Jackson.
In the meantime, one former dentist isn't yet convinced.
"Some people are more anxious than others and it doesn't really depend on the colour of their hair," says Gordon Watkins, who practised dentistry in Norwich for more than 40 years. He is currently a member of the British Dental Association's Health and Science committee.
"I don't have any recollection of redheads who had any more pain than the rest of the population," he says.
Below is a selection of your comments.
My sister is ginger and she's got the highest pain threshold of anyone I know! She was able to climb over a wall and walk for some distance after she had completely broken her ankle. I'm dark haired, and I'm actually the one who needs more anaesthetic at the dentist. Once, I had to have four injections in the one tooth because I could still feel everything...
Laura, Ballymoney, County Antrim
I am a redhead and require more anaesthesia than normal in order to have my gums numbed prior to dental treatment. My skin is also highly sensitive to sunlight, heat and I use lotions and shower gels for sensitive skin. Truly there is something to this
Madeline Koko, Dunganon, NI
I've got red hair (it's ok, you can say ginger if you like) and while I like the idea of having a different pain tolerance to everyone else (I am either tough for putting up with more pain, or tough for putting up with more perceived pain. It's a win-win situation.) I don't really see the point of this research. Unless someone, somewhere, is planning to start some sort of ginger revolution where we will rise against the rest of the nation, what good will it actually do? If you want to do something that really is of value to us gingers, invent a permanent mascara that is halfway decent.
I am a red head, and all my life I have had to tell dentists that I need extra meds to go numb. Most do not believe me, until they see me react when they touch my teeth, but all have then given me more, so I am not anxious about the dentist. Also when I had my C-section, they gave me two doses of the epidural, but were still surprised that I could move my feet. They knocked me out completely instead! I now find that both dentist and anaesthesiologists are aware that red-heads are different, but it is still the first thing I say when I go see someone new!
Jo, Virginia Beach, VA