Scientist convinced it's possible for us to to become younger and live to be much older than we do now.

Dr Bill Andrews isn't joking when he says he doesn't plan on dying.

The United States biologist, who visits New Zealand next month, is at the forefront in the field of life-extension science - with the goal that he and others may live far longer than anyone has before.

Dr Andrews told the Herald his ambition doesn't stop there. He also thinks science could be able to reverse the ageing process.

While this might seem limited to far-fetched fiction such as the film The Curious Case of Benjamin Button, tests on engineered mice have convinced Dr Andrews it is possible to bring us back to the ripe age of 24.

His research focuses on the telomere - a structure at the end of chromosomes that protects the chromosome - and telomerase, the enzyme that replenishes the telomere.

In 2009, US scientists Dr Carol Greider, Professor Jack Szostak and Professor Elizabeth Blackburn won the Nobel Prize in Physiology or Medicine for discovering telomerase.

Dr Andrews and his colleagues believe that by lengthening the telomeres in certain cells by engineering the activation of telomerase, either temporarily or permanently, human life could be extended.

"Let me use one analogy - if you think that each cell of our body has multiple sticks of dynamite burning inside them, and they are all ageing processes that are occurring. But it's only the stick of dynamite with the shortest fuse that we have to worry about.

"I'm convinced that the stick of dynamite with the shortest fuse is telomerase. But even if we put that out, we may still have to put out other fuses."

Dr Andrews is a named inventor on 45 US-issued patents on telomerase and his company, Sierra Sciences, has been researching telomerase with funding from wealthy private investors looking to lengthen their own lives.

"We've already spent around US$33 million [$42.59 million] to get where are, and we'd estimate we'd need another US$40 million to get it to the testing of a human drug that will actually make humans younger."

Nevertheless, Dr Andrews claims it could be just years before products are launched that lengthen age.

"Right now, there is a theoretical maximum of 125 a human can live to. I think people will be living at least to 130 - and they will be a lot healthier when they do so." He was also confident age-reversing products could become a reality.

In 2010, US researchers demonstrated that by engineering mice with a controllable telomerase gene, age-related degeneration could be reversed to the point that the mice developed new growth of the brain and testes, improved fertility and a lost cognitive function returned.

"When we are first born, we start to develop and we age at the same time. A lot of scientists believe that development ends at about 24 years old, so after that you essentially are fully developed, and then you just age," he said.

"We think we will reverse people to 24 years old, so part of my focus is how to be 24 again."

So just how certain is he that his heady theories may become reality?

"I don't ever plan on dying," he said.

"Because I believe in myself and I believe that my research is going to find solutions to every problem that I encounter ... and I'm just going to keep going and going."

While here, he will visit Auckland University.

Waikato University demographer Professor Natalie Jackson said the number of Kiwis over 65, now about 620,000, was expected to balloon to 1.2 million by 2031. On current trends, about 90 per cent of children born today would reach 65.

Living past 125 years the new grail

The Holy Grail or pseudo-science?

Dr Bill Andrew's company Sierra Sciences is doing research on telomeres - structures at the end of our chromosomes that shorten every time a human cell divides.

The length of an individual's telomeres is closely associated with their biological age, and research suggests that control of telomere length has the potential to treat many diseases associated with ageing, and possibly to allow humans to live at a physiologically "young" age beyond the current theoretical maximum human lifespan of 125 years.

One of the most well-known and controversial promoters of the concept is English theoretician Dr Aubrey de Grey, who believes preventative medicine, including gene and stem cell therapies, could push out lifespans.

In 2005, the Massachusetts Institute of Technology journal Technology Review offered a US$20,000 ($25,800) prize to any molecular biologist who could prove Dr de Grey's theory was "so wrong that it was unworthy of learned debate".

It was never won.

By Jamie Morton Email Jamie