The bacteria that cause acne may protect sufferers from other infections and cancer in later life.

Scientists believe that the presence of the bugs, known as propionibacteria (P. acnes), may help to crank up the immune system so that is more effective at tackling subsequent infections.

It appears that P. acnes stimulates activity among a type of white blood cell called a Th-1lymphocyte which plays a central response in fighting infection.

Acne may simply be the price we pay for a natural defence mechanism

These cells specialise in fighting bacteria and viruses. However, they can also be mobilised to attack some types of tumour cell.

Dr Anne Eady, of the Skin Research Centre at the University of Leeds, said there was evidence that certain skin cancers are less common in people who once had acne.

She told BBC News Online: "P. acnes is what we call an adjuvant - when it triggers an immune response it does so non-specifically so that it enhances immunity to unrelated antigens (proteins that act on white blood cells) including bacterial, viral, parastic and tumour cells."

Puberty

It has been shown that acne can develop well before any other signs of puberty - sometimes in children as young as six.

Dr Eady's team are hoping to develop a test to predict which children are at risk so that they can be treated early to reduce the severity of the disease.

However, she admits that her work, while helping some to avoid the misery of a disfiguring condition, may actually be counter productive in other ways.

Dr Eady said: "Acne may simply be the price we pay for the optimum performance of a natural defence mechanism.

"If acne is eliminated we may begin to pay a much higher price as the incidence of certain cancers starts to rise.

"One day we may all be popping pills of P. acnes in a bid to stay healthy."

Acne is a disease of the tiny hair follicles found on the skin.

Each follicle is surrounded by glands that produce a protective oily substance known as sebum.

People with acne produce excessive amounts of sebum, which clogs up the follicle, and provides and ideal breeding ground for P. acnes.

Chemicals produced by the bacteria cause inflammation in the follicle and surrounding skin which results in the spots typical of acne.

The research is published in the magazine Microbiology Today.