What I learned about getting older: The scarlet letter 'A' is for ageing

By Dr Sanjay Gupta, CNN's chief medical correspondent

Ageing. It's funny how a biological process we all go through, individually and collectively, is a concept we try not to think about, much less talk about with others. When I started work on this season of the Chasing Life podcast, which is all about being your best self at every age, nobody on the team even wanted to say it out loud, believing that it might turn off listeners. In our youth-obsessed society, "ageing" truly has become a four-letter word.

But over the course of the season, I have learned so much about getting older, the myths and the realities, and what it takes to be in the best physical and mental condition during any stage of life. The truth is, neither the word nor the idea of it bothers me anymore.

Words of wisdom to my younger self

Many of us, myself included, carry around plenty of preconceived notions of what life is going to be like when we are "old": that it will be a time filled with aches and pains, depressed moods, poor sleep and eventually disease, infirmity and hospitalizations. But as I learned after dozens of interviews, including with my parents, my millennial brother and one of my childhood friends, these preconceptions are not necessarily the case.

That's why the first piece of advice I would give my younger self is to take the time to talk to people from older generations. Ask them questions; you may be surprised.

My mother astonished me by telling me she sleeps eight to nine hours a night, is generally always in a good mood and - remarkably - has none of the expected aches and pains.

"I just turned 81, and I feel great. I'm happy. I probably feel younger than my age because I'm pretty active. I don't like to just sit around, you know, and do nothing," she told me.

She added that she and my father try to follow a health-promoting lifestyle, which includes a regular mental reset. "I want to live healthy, So I don't want to bring any negative thoughts in my mind. I just … get up and do my routine every day. I go to bed early, and I get up early, and we walk. We do water aerobics. We go to the gym. … I enjoy cooking very much, having friends over. So life is good," she said.

Then there is my friend Diana Nyad, the long-distance swimmer. She swam from Cuba to Florida at age 64 after five failed attempts, including the first when she was more than three decades younger. Now, 10 years beyond her incredible accomplishment and on the cusp of turning 74, she still shows no signs of slowing down.

"I'm 73, and I feel pretty damn good," she told me, adding that twice a week, she does a thousand burpees (minus the pushups) in her garage.

"I was at a gathering, a talk, and we had a little Q&A afterwards. And one woman stands up at the microphone and she says, 'You know, Diana, I'm exactly your age, and you know how it is at our age. You get up and you're just stiff, your knees and your shoulders." And I said, 'With all due respect, you have to speak for yourself. Don't go around saying all people our age are feeling this. I feel no stiffness whatsoever. I wake up in the morning and I bound out of bed, loose and limber and ready to go.' And I do think that at the bottom of that, besides mental attitude and genetics … is just movement … like your mom. I know your mom's a pretty active person, so she's not sitting around," she told me.

While most mere mortals could not copy what she did, Diana's success for me really blows wide open the possibility for anybody to achieve, at any age, things that are not typically considered attainable - an idea that brings me comfort as I approach 54.

And then there's another friend, author, producer and explorer Dan Buettner, who has spent the latter part of his career identifying Blue Zones, which refers to five regions around the world that have the highest concentration of centenarians, and analysing what specifically about them causes people to live longer.

At 63, Dan still said he still feels as good as he did when he was 35.

"I can bike 100 miles like I could back then. I'm probably not as fast. … I probably can't lift quite as much. But the way I wake up in the morning, the way I feel right now - I have no pain, I have energy, I have mental clarity. I feel great," he told me.

The real lesson for me is that when you really start to spend time with people who are older and listen to their stories, a much more optimistic picture emerges - not for everybody, but for a lot of people.

Sanjay Gupta
For my best friend Sujit, left, and me, being over 40 was unimaginable when were were teens. Photo credit: Sanjay Gupta / CNN

That brings me to the second piece of advice I would give my younger self: Attitude matters. As I said earlier, in this country, we live in a youth-centric society that has long peppered us with anti-ageing messages, including the TV shows we watch that play the foibles of older folks for laughs and the anti-ageing surgeries and miracle solutions advertised everywhere.

It turns out that our attitudes about ageing - our "age beliefs" - affect our own mindset and can actually affect our lifespan, according to Yale professor and author Becca Levy.

One of Levy's groundbreaking studies from 2002 found that people in the United States with more positive self-perceptions of ageing lived on average 7.5 years longer than those with a more negative view of ageing. She said positive age beliefs can affect us psychologically, behaviorally and biologically. And her studies have found that the reverse is also true: Harbouring negative stereotypes can result in worse health outcomes, including a higher risk of cardiovascular events such as heart attack and stroke and even Alzheimer's disease.

"Children as young as three have already taken in the age beliefs of their culture, and then those are reinforced over time," she told me.

Levy was inspired to carry out her research after spending time in Japan, where she witnessed the celebration of ageing and reverence for the elderly. It's probably no coincidence that people in Japan also tend to live in multigenerational households, and the older population isn't sequestered in retirement communities or nursing homes, so positive age beliefs are more easily perpetuated.

Levy said we all need to find ways to resist and overcome negative stereotypes, and be diligent about it in our daily lives. "We've all taken in messages about what it means to be different ages and different ideas about what improves and what declines. But I don't think we're all aware of the age beliefs. So I think we all have them, but we don't always check in with them and think about what they are and think about which beliefs are beneficial and which ones are harmful," she added.

While my three teenage daughters and my near-octogenarian parents talk often, I have made a renewed effort for them to spend dedicated time together. So even though we don't live together in a multigenerational home or even the same state, my daughters get to see their grandparents thriving and hear the stories of their lives. I do that because it's good for my parents to have that time with their grandkids but also for their grandkids - my kids - to develop these really positive age beliefs.

The third piece of advice is: Keep your body in the best shape possible, because it is the vessel that carries you from cradle to grave. (And an equally important corollary: What's good for the body is good for the brain.) That means doing all the things we know we should be doing: eating right, not smoking, getting enough sleep, drinking in moderation (if at all), reducing stress, interacting with family and friends, and engaging in regular exercise.

Dan Buettner, Diana Nyad and my mother have at least one thing in common besides feeling great in their 60s, 70s and 80s, and that is, as Diana said, movement. They haven't let the gravity of life pull them onto the couch to grow rusty. That doesn't mean you have to do 1000 burpees in your garage or bike 100 miles, but even doing something as simple as walking regularly can be very beneficial. In fact, I think the healthiest periods of my life were when I lived in walking cities, because that low-key physical activity was just baked into the day.

As you get older, however, there should also be an increased emphasis on weight training and fast-twitch exercises. These types of movements are even more important with age to help maintain strength and prevent falls. Your best bet, according to Buettner, is to make all these pursuits part of your natural environment so the healthy option becomes the default option.

I remember talking to Ellsworth Wareham in 2015; he was a retired cardiac surgeon who operated on hearts until the age of 95 and eventually died at age 104. He lived in Loma Linda, California, a Blue Zone where about a third of the residents are Seventh-day Adventists; healthy living is central to their faith. Wareham ate a vegan diet, did a lot of physical activity (including walking and mowing his own lawn) and did not smoke or drink. To recharge, he kept a strict Saturday sabbath. He told me that he does not experience stress.

But he didn't do any of this alone; he was part of a larger community, one in which the prevailing social network reinforced healthy behaviour.

I want to take a step back to remind you that even if you haven't been living a life that is perfectly aligned with what I am describing, it is never too late to start. I have met people in their 70s who started incorporating consistent movement and social interaction into their lives for the first time, and what they learned was that even small changes at any age can have a positive, meaningful impact.

Biohacking or B.S.?

In this season of Chasing Life, we also explored efforts - both individually and as part of the scientific research community - to extend longevity. Some refer to the field as biohacking, changing your natural biology in the pursuit of additional healthy years of life.

I spoke to Dr Nir Barzilai, a professor at Albert Einstein College of Medicine and the director of the Einstein Institute for ageing Research, who believes the human lifespan is closer to 115 years instead of the current average of 76 years. In addition to "leaving nearly 40 years on the table," as he described it, he thinks slowing ageing would dramatically reduce age-related diseases, increasing not only lifespan but health span, as well.

To do that, researchers like him are targeting the essential biology of ageing - the underlying reasons why we get old. Barzilai said a number of hallmarks of ageing have been identified. They are biological processes that happen at the cellular level, such as stem cell exhaustion, mitochondria dysfunction and epigenetic alterations. When those biological processes fail or break down, we get sick - and ageing is the biggest risk factor for that deterioration.

"Ageing is the mother of all those diseases," Barzilai told me.

Although a lot of the research into stopping, reversing or preventing the hallmarks of ageing is happening in the lab or in animals, some of it is occurring in humans. Metformin, a medication long used to treat Type 2 diabetes, shows some promise.

"Metformin is one of those drugs that target all the hallmarks of ageing, and there is a lot of convincing literature," Barzilai said. "But more than that, there are studies that show that people on metformin don't get diabetes, that people on metformin don't get cardiovascular disease … get less cognitive impairment. … So we have a lot of data on that. And that's the drug that I chose to go to the FDA and say … 'We will prove to you basically that ageing can be targeted.'"

Metformin, which is a generic drug, is not without side effects. The most common is GI distress; other side effects are rarer but more serious.

Barzilai said that he himself is taking metformin and that he fasts, eating only during a specific window of time, all in the hopes of slowing down the ageing process.

All that research is very interesting - and I am glad Barzilai and others like him are working on it - but the truth is that it will take a long time to validate. And even if metformin or something else addresses some of the hallmarks of ageing, it doesn't guarantee that it will lead to a longer life.

These are just some of the lessons I learned during these amazing conversations. There are a lot more; I encourage you to check out the whole season.

In the meantime, though, remember this: ageing is probably not nearly as bad as you might imagine. Spend some real time talking to older people, and learn for yourself. And as my mom told me, we should all truly embrace getting older, because it sure as heck beats the alternative.

CNN's Andrea Kane contributed to this report.