A pill that will keep you youthful?

By taking a pill a day from middle-age, people will be able to grow old free from illnesses of the body and mind such as Alzheimer`s and heart diseases, the `Daily Mail` reported.

"I would be surprised if there weren`t things within ten years. If told you could take a drug that has minimal side-effects and that`s going to keep you healthy for another five or ten years and then you`ll drop off your perch without disability, most people would want it," Prof Partridge said.

Extraordinary as the professor`s prediction may seem, it is based on a host of promising scientific studies from around the world. They have discovered key genes linked to longevity and health, and found ways of tinkering with them, at least in animals.

In one of the remarkable examples, a Harvard University doctor made old mice young again, in experiments that mirrored the plot of The Curious Case Of Benjamin Button, where the lead character played by Brad Pitt ages in reverse.

At the start of the experiment, the animals` skin, brains, guts and other organs resembled those of an 80-year-old person. Within just two months of being given a drug that switches on a key enzyme, the creatures had grown so many new cells that they had almost completely rejuvenated.

Remarkably, the male mice went from being infertile to fathering large litters.

Prof Partridge said: "The principle is for drugs that if taken from middle-age will ward off quite a broad array of diseases rather than doing things piece-meal or acting when the diseases appear.