Young men shouldn't have operations as soon as they start losing hair, according to one of the country's leading hair transplant surgeons.
He has told Newsbeat some clinics are not doing enough to warn under-30s about the long-term risks.
Doctor Bessam Farjo says he has had enquiries from men as young as 19 but does not recommend hair transplants for under-25s.
I ask them questions about their family history, record the hair loss and monitor it over a period of time. I also offer them medication to see if their hair stops falling out
Doctor Bessam Farjo
He is warning men to avoid surgery until they are closer to the age of 30.
He said that while the publicity in celebrities like Wayne Rooney getting the procedure is making it more popular, it is not for everyone.
"When a celebrity comes out with it, you only hear the good things," he said. "You don't hear the cautions or the potential complications."
He says that if you get surgery too young, it can look worse than it did in the first place.
He said: "If you have the surgery too early and you go bald, you don't have enough hair to keep chasing the hair loss.
"You can end up with isolated patches of hair. You could end up with hairy temples and a bald forehead which isn't pretty but is also hard to fix."
Dr Farjo says when younger patients come to see him his priority is to preserve the rest of their hair from falling out before talking about surgery.
England footballer Wayne Rooney had a hair transplant in June aged 25
"I ask them questions about their family history, record the hair loss and monitor it over a period of time," he said.
"I also offer them medication to see if their hair stops falling out.
"I am then able to have a much fuller picture of how much hair they will lose."
Jon from Merseyside has been losing hair since he was 20.
He says he used to style his hair to hide his bald bits.
"It's a massive blow to your confidence when your hair line changes," he revealed.
Jon is now having surgery at 29 and says he is glad he waited.
Newsbeat spoke to 16 hair transplant surgeons.
Thirteen said they agreed with Dr Farjo and would be reluctant to operate on men under 25.
But there is no code of conduct or regulation to force hair transplant surgeons to stick to a minimum age.
Other surgeons have told Newsbeat that there should be a regulatory body to stop abuses in the industry and to make sure clinics give people the best possible advice and treatment.
Dr Farjo, who runs the The Farjo Medical Centre with his wife Nilofer, admits there's no concrete way to stop some clinics putting money before the wellbeing of patients.
However, he thinks that surgeons should work together to educate each other and their patients about risks.
Newsbeat contacted the clinic in London's Harley Street where Wayne Rooney had his operation.
They said: "Each case is judged on its own merit. Wayne is intelligent and knows the risks."