How much ageing can be reversed is still in the realm of science fiction. But scientists seem confident of stopping the hair from turning grey.
The Paris-based L'Oreal says that the greying of hair can be prevented with a pill based on a fruit extract. The daily medication is due to be launched within four years.
It is the result of more than a decade's research at the laboratories of L'Oreal. The cosmetics major hopes to win the race to capture the world's Ģ8 billion (approximately $12.9 billion) hair colour market.
Bruno Bernard, the company's head of hair biology said: "We have a watertight proof of concept with this, and we think it will have a market among men as well as women."
The research team has published papers in specialist journals explaining how the absence of a protective enzyme called tyrosinase-related protein 2 (TRP-2) causes hair pigment cells to die with age.
Rather than develop a synthetic drug to mimic TRP-2, which would involve exhaustive clinical trials, the company screened thousands of naturally occurring compounds that humans are already exposed to, and found one in an unidentified fruit.
Another good news is it might not be expensive.
Safety trials are being undertaken with volunteers around the world but L'Oreal acknowledges the pill's real efficacy will not be proved until it has been on the market for at least a decade of use in the market, because hair-greying is such a slow process.
Details will not be unveiled until the five-yearly International Investigative Dermatology meeting in May 2013.