Men who show signs of baldness before age 30 may have less chance of developing prostate cancer, according to a study at the School of Medicine, University of Washington in the United States, and published in the journal Cancer Epidemiology.
Between the 2 thousand men that were studied, cancer incidence was 45% lower.
The researchers studied 2 thousand men between 40 and 47 years of age and noted an apparent link between high levels of the male hormone testosterone - as men who become bald early - and a lower risk of having the disease.
Half of the men who participated in the study suffered from prostate cancer. The researchers compared the incidence of tumors among those who said they had begun to lose hair before age 30 and those who reported having experienced falls.
Those who began to be bald by the 30 had a risk between 29% and 45% lower risk of prostate cancer.
The researchers believe that between 25% and 30% of men show signs of baldness by the age of 30. Half the men have suffered significant hair loss up to 50 years of age.
Baldness occurs when hair follicles are exposed to a very large amount of dihydrotestosterone (DHT) - a substance produced by testosterone.
Experts believe that men with higher levels of testosterone are more likely to lose hair, especially if there are cases of baldness in the family.
It's common for patients with prostate cancer do therapy to reduce testosterone levels because the hormone can accelerate the growth of some tumors, as they appear.
But this study suggests that high levels of testosterone at a young age may actually protect against the disease.
"Clearly, the age at which a man begins to lose hair is unfortunately (indicator) a risk factor for prostate cancer on which we have no control," said Helen Rippon, head of the administration's research Foundation The Prostate Cancer. "If the results (of research) are correct, they may be useful to increase our understanding of how testosterone behaves in the human body and how it can affect different tissues."
Alison Ross, Research Foundation Cancer Research UK, said the link between prostate cancer and baldness is still unknown, because previous studies showed an exactly opposite result to this.
"The results (of the new American study) are based on asking men aged between 40 and 70 years if they remember it started to get bald at age 30, does not mean a highly reliable," she said.