Longevity isn’t just about living a long life but also about living well.

More than one in five Americans will be 65 or older by 2040, the U.S. Department of Health and Human Services projects. And more than 56 per cent of those turning 65 will need some sort of long-term service.

Fortunately, there are things you can do at any age to ensure that you will maintain your health as the years go on, according to Dr. John Batsis, a geriatrician at the University of North Carolina at Chapel Hill.

Batsis, an associate professor at UNC’s School of Medicine and Gillings School of Global Public Health, spoke with CNN about what people should know about healthy aging.

This interview has been lightly edited and condensed for clarity.

CNN: Some people may find it hard to relate their health behaviours now to outcomes in their later years. Why should people start to think about healthy aging early?

Dr. John Batsis: There will be individuals who may become sick and frail. There will be individuals who are robust into their 90s. I have patients who are still extremely fit and active — they may not be as active as they were 20 years ago, but they are still doing the things that they want to do.

You have to find a sense of self, a sense of purpose. You have to find a sense of what makes you happy, and it may be different at each stage of life.

You can’t change your genetics; you can’t change your past. You can try to change your future with things that are modifiable. If it means altering what you’re eating or how much you’re exercising or engaging in the community, or stopping smoking or drinking — these are things that are in your control. And there are tools — like working with your health care team and community resources — that may be available to be able to help you achieve those.

Part of it is really getting to a point that you’re saying, “Yeah, I’m willing to change.” You have to be willing to change to effect that change.

CNN: What are the things you would like people to change earlier in their lives to impact how they age?

Batsis: That’s a really great question, and one that often is asked to me — not only by my patients but their children and by my own family and friends as well. There are a number of factors that have been shown time and time again to lead to healthy aging, but really you can kind of drill it down to kind of a couple.

First is proper nutrition, and that really starts from infancy to childhood into adolescence and throughout even into old age. Secondly, regular physical activity and exercise are critically important. And then the third big category is social connections.

We often think about these independently as silos, and really you need to be thinking about these jointly and together and synergistically. One can affect the other, but it’s really kind of the sum of the parts is greater than the whole.

CNN: What do you mean by proper nutrition?

Batsis: We often think of healthy nutrition as having a balanced diet, a Mediterranean-type diet.

The food environment often can be challenging, particularly in Western industrialized societies. The fast-food industry is very difficult to get away from. But home-cooked meals — cooking your own fresh fruit and vegetables, thinking about having these types of meals — is really, really important and nutritious. Really try to stay away from processed foods and think about more holistic type of foodstuffs.

This is really thinking about it more consistently. Food is medicine, and I think this is a concept that is increasingly being sought and advocated by both health and nonhealth providers.

And this kind of goes beyond aging. Start young, start early, get it into schools and start to engage individuals and children early on, so they develop skills and practices that are sustainable over their lives. It becomes part of the routine, and it’s not thought to be a chore.

CNN: What kind of exercise is most important?

Batsis: Regular walking, regular activity. The 150 minutes of activity per week divided by 30 minutes over five days of moderate activity is what’s really recommended. In addition to that, one should think about not only aerobic activity but resistance-based activities. This is more important as one ages to maintain muscle mass and muscle strength, because we know that you lose that capability to maintain that as you age.

CNN: Why is social connection so important?

Batsis: The importance of social connection in aging is often overlooked, understudied and underappreciated. One of the challenges here in our country is that a lot of us are spread out. And this is not seen as much in other countries that are geographically not as dispersed, or where family units are right next door or within the same neighbourhood.

It’s not uncommon where I have patients whose children may be on opposite ends of the country, for instance, or their friends may be on opposite ends of the country.

The social networking is really helpful to engage in stimulating conversations. And it’s a sense of self, it’s a sense of well-being, it’s a sense of purpose, it’s sharing stories, sharing community. It’s having fun. It helps one’s mental health. We know that depression in individuals can be a risk in old age, and it’s really challenging.

CNN: What about the older adults who are reading this? Does the advice still apply?

Batsis: Healthy aging can occur at any stage of life. It’s not only as a young adult or middle-aged adult, not only around retirement age. It still can occur well into one’s 80s and 90s.

The definition of what constitutes healthy aging may differ, and it’s really about asking what does it mean to you? What’s important to you at this stage of life? How can we achieve what is important to you, and then coming up with a plan and strategies to help our individual patient achieve that? That is the key, and it shouldn’t be a top-down approach. It really needs to be engaging the patient, figuring out from within what is important to them, and helping them and giving them strategies to help them achieve what’s important to them. It comes from within.