Like a bad fairy tale, scientists believe they have developed a way to stop people getting older, but at a cost that puts it out of the reach of all but the super-rich.

A team of researchers at the University of New South Wales, working in collaboration with geneticists at Harvard Medical School, claim to have unlocked the secret to eternal youth, and to have developed a compound they say not only halts the ageing process, but can turn back the years.

The catch is, the treatment is prohibitively expensive, with estimates it would cost the average 86 kilogram man $43,000 a day, and the average 71 kilo woman $35,500 a day.

The compound was developed based on an understanding of how and why human cells age.

A series of molecular events enable communication inside cells between the mitochondria – the energy source for cells, enabling them to carry out key biological functions – and the nucleus. The researchers found that when there is a communication breakdown between the mitochondria and the nucleus of the cell, the ageing process accelerates.

As humans age, levels of the chemical NAD (which initiates communication between the mitochondria and the nucleus), decline. Until now, the only way to arrest this process has been through calorie-restricted diets and intensive exercise.

But the researchers, led by University of New South Wales and Harvard University molecular biologist Professor David Sinclair, have developed a compound – nicotinamide mononucleotide – that, when injected, transforms into NAD, repairing broken communication networks and rapidly restoring communication and mitochondria function.

In effect, it mimics the results achieved by eating well and exercising.

“The ageing process we discovered is like a married couple. When they are young, they communicate well but, over time, living in close quarters for many years, communication breaks down,” Professor Sinclair said. “And just like a couple, restoring communication solved the problem.”

In the study, the researchers used mice considered equivalent to a 60-year-old human and found that, within a week of receiving the compound, the mice resembled a 20-year-old in some aspects including the degree of muscle wastage, insulin resistance and inflammation.

Professor Sinclair said that, if the results stand, then ageing may be a reversible condition if it is caught early.

“It may be in the future that your age in years isn’t going to matter as much as your biological age,” Professor Sinclair said.

“What we’ve shown here is that you can turn back your biological age or, at least, we think we have found a way to do that.”

The problem is, the compound is prohibitively expensive, at least at the moment.

It costs $1000 per gram to produce, and in tests so far it has been applied at a rate equivalent to 500 milligrams for every kilogram of body weight, each day.

Professor Sinclair admitted the cost was major consideration, and said the team was looking at was to produce the compound more cheaply.

As part of their research, the scientists investigated HIF-1, an intrusive molecule that foils communication but also has a role in cancer.

It has been known for some time that HIF-1 is switched on in many cancers, but the researchers found it also switches on during ageing.

“We become cancer-like in our ageing process,” Professor Sinclair said. “Nobody has linked cancer and ageing like this before, and it may explain why the greatest risk of cancer is age.”

Researchers are now looking at longer-term outcomes the NAD-producing compound has on mice, and suggest human trials may begin as early as next year.

They are exploring whether, in addition to halting ageing, the compound can be used to safely treat a range of rare mitochondrial diseases and other conditions, such as cancer, type 1 and type 2 diabetes, muscular dystrophy, other muscle-wasting conditions and inflammatory diseases.

The research was published in the journal Cell.

Kirsty Waterford