Could 80 become the new 40?

For all the advances in medical technology humans have developed, there is one thing it hasn't been able to do: stop us from getting old.

We've managed to extend the human lifetime dramatically in the last couple of centuries, greatly diminishing infant and child mortality and pushing back on disease with antibiotics and vaccines.

But the general trajectory of life endures: once we get into the last quarter of our lives, our health gradually declines.

That may soon change, as researchers focus on treating the diseases and conditions that plague us as we get older. It's not impossible that we might soon see medicines that greatly improve and maintain our health and independence as we head into our golden years.

There are "genetic, biochemical, molecular biological mechanisms that occur as we age and that actually drive the onset and progression of most of the changes that we think about," said Matt Kaeberlein, a professor of laboratory medicine and pathology at the University of Washington. 

Andrew Steele, a biologist and the author of  Ageless: The new science of getting older without getting old, agreed. "Until now, we've been treating medicine in this very unsystematic way. In a sense, we've been picking off the endpoints of aging, things like cancer and heart disease, without actually addressing the fundamental underlying causes that are resulting in those diseases. So what we could do by understanding these hallmarks, is potentially come up with treatments to intervene in them directly. And that means preventative treatments, treatments can go in earlier and stop people getting ill in the first place."

What all this means in a big sense, is that we stop talking about human lifespan—the length of time a person is simply alive, between birth and death—and start focusing more on health span, or the period of our lives where we are healthy, independent and strong.

Kaeberlein has isolated a number of aging "hallmarks" that are good indicators of our overall health as we age—things like chronic inflammation, cellular senescence (where cells stop dividing) and other issues. The good news, he said, is that these are all things that are possible to address therapeutically.

So rather than treating aging as a single, inevitable change in our bodies, it's more like a series of processes brought about by disease. If those processes can be prevented, or even reversed, then the health span of people could dramatically increase, along with being able to live considerably longer.

And the idea of stopping some of these processes isn't science fiction, Steele told Spark host Nora Young.

There are already treatments for cellular senescence, he said, drugs that target these redundant cells and remove them, along with the toxic cocktail of molecules that accompany them and contribute to heart disease and cancer.

Using these treatments on mice essentially made the mice "biologically younger," he said. "It's not as though they were hobbling along in a sort of geriatric state, which has somehow been extended by this anti-aging treatment. What they found is that the mice were healthier too. So they got less cancer, they got less heart disease, they got fewer cataracts, they were less frail."

That's an important concept to get across, the scientists said. Most people, when they think of increasing human lifetimes from, say, 80 to 120 years, assume that this means we'll just be very old for a longer time, which doesn't hold a lot of appeal. But if we could live to 120 and be healthy and active until we're, say, 118, then that's a much more attractive proposition.

Besides using medicine and technology to increase human health span, it's also vital that we rid ourselves of the bias against the elderly and ageism more generally, said Becca Levy, a psychologist and epidemiologist at Yale University, and the author of Breaking the Age Code: How your beliefs about aging determine how long and well you live.

Our culture, particularly in North America, is saturated with ageism, she said, whether it's billboards promoting expensive skin creams or merely disregard for our elders.

Worse, as we age, we come to assume that those negative sentiments about being old are true, leading to a measurable diminishment in health and quality of life.

Levy pointed out that in Japan, whose residents typically live longer than anywhere else on the planet, the elderly are treated like rock stars, and they even have a national holiday to celebrate older people!

"Is it possible that the way that the culture is celebrating and integrating older people, could that be a factor that's contributing to their longer lifespan?" she said. 

Kaeberlein and Steele concede there is often pushback to the idea of living longer, with concerns about overpopulation and societal change. They agree this is largely illogical.

"Let's say I had written a book on cancer research and how I think we're going to cure leukemia in the next 20 years. Literally, nobody would write me an email saying, 'Hi, Andrew, you know, this cancer research, aren't you really worried about all these extra people who are going to be surviving cancer and cluttering up the planet'?"

Moreover, the impact on global population wouldn't be nearly as dramatic as people assume, Steele added.

Both are optimistic that there are likely to be medications available to target the causes of disease and dysfunction in the elderly appearing within the next decade or so. 

The bigger ethical issue, Kaeberlein said, is making sure these medicines are available for everybody, and not just the wealthy.

Steele agreed: "The reason that you invest in this research, the reason you do this research, is you want to prevent cancer, you want to prevent dementia, you want to prevent all of these horrible diseases, and actually living longer is going to be a side effect, as it has been from all kinds of improvements in human life that we've already talked about over the last 200 years."

Written and produced by Adam Killick