ANTI-AGEING1

Famed for pioneering procedures including face lifts, tummy tucks, botox and skin peels, America's obsession with youth is no secret. For people with a bit of nerve and a lot of cash it's now considered the norm to do what it takes to claw back the last few years of their radiant youth. But how far is the average American willing to go? A few botox injections leads to liposuction, a face lift, and then where?

The latest craze to sweep the States is human growth hormone (hGH) injections. Going beyond simple external aesthetic enhancement, medical practitioners have claimed that a hGH regime can actually reverse the physical effects of ageing leaving subjects not only looking younger, but feeling it too.

Doctors advocating the use of hGH suggest getting older and fatter need no longer be inevitable. It's the result of a glandular disorder that is caused, in part, by diminishing hormones. By replenishing hormone levels to that of a 20 or 30-year-old, it is possible to once again feel that young.

Growth hormones (which are naturally produced in the pituitary  gland of the brain) work by inducing the liver to produce inculin-like growth factor 1 (IGF-1), which triggers the growth of bones and tissues. Levels of hGH and IGF-1 naturally decline after the age of 30, though the pituitary never stops producing them completely. Some small studies have shown that boosting these levels with hGH injections can lead to an increase in muscle mass, improved exercise capability and an increase in skin elasticity.

But of course, it comes at a price. Enterprising cosmetic doctors charge between $500 and $1,000 a month for hGH injections, but the real cost lies in the risk to an individual's health. Studies have shown that high levels of hGH can lead to an increased likelihood of breast and prostate cancer. Scientists believe this could be because IGF-1 promotes the growth of cells and prevents them from dying - this is the same as with cancer cells which grow rapidly and don't die.

Other risks (which can be seen in sufferers of acromegaly, a disease caused by a tumor that makes growth hormone) include swollen features, hypertension, heart disease and arthritis.

Aside from the glowing anecdotal testimonies, there is little scientific evidence to support the anti-ageing claims made by fans of hGH. In fact, a 2007 study of healthy elderly men and women showed that the positive effect of the hormone was comparable to what could be achieved by moderate weight training in the gym.

For now it seems we must continue to herald a diet rich in antioxidants (vitamins A, C and E), along with regular exercise, as our best weapon in the fight against ageing. It's not the secret to eternal youth, but it may just help you grow old gracefully.