We’ve been hearing more and more about the “last-mile” problem since Covid-19 vaccines were distributed. The term is used in the transportation, supply chain management and telecommunications industries to describe the difficult last leg of a journey — the often costly challenge of actually delivering goods or services to consumers. It’s the idea that, for all the difficulty of producing the vaccines and distributing them to states and cities, the biggest challenge is turning out to be the very last stretch: actually getting the shots into people’s arms.

As necessary as it was to solve the last-mile problem in the height of the pandemic, transformative change for our health and well-being at large can come only by solving the first-mile problem. Putting our focus, along with our funding, on the first mile is going to be the next era in healthcare. Health isn’t a product, or a service, or a treatment. It’s not delivered, like a package, to the consumer. It’s a mindset and a way of living. It’s the sum total of our daily experiences. A first-mile approach means shifting our mindset around health and well-being, both in our individual lives and collectively. If we can solve the first-mile problem, it’s not just that the last mile gets easier, we’ll have an entirely different journey. It will be one that's not only happier, healthier and less costly, it will also be a longer journey, since we’ll be putting more miles between our first mile and our last one.

Right now, our focus on the last mile means dedicating an incredible share of our resources to downstream harm reduction. That is, trying to fix health problems after they’ve taken hold. According to the Centers for Disease Control and Prevention, an astounding 90% of our $3.8 trillion in health care spending goes toward the treatment of mental health conditions and stress-related chronic diseases that can be managed and even prevented, like heart disease and diabetes. In the U.S., chronic disease accounts for 7 out of 10 deaths. Heart disease and strokes alone kill over 868,000 Americans each year.

The last mile isn’t just a very late intervention point, it’s a very costly one, in both lives and money. Chronic diseases are notoriously hard to treat. Wouldn’t it be much better, for all involved, to empower people to avoid chronic diseases in the first place? That requires a collective mindset shift. As Dr. Michelle Williams, Dean of Harvard’s T.H. Chan School of Public Health, says, getting treatment and surviving a disease isn’t the sole outcome we should be striving for: “Health is more than the absence of disease. Health is really about wellness and a capacity to thrive.” According to Dean Williams, “the new front door to health and wellness” should focus on allowing us to put off needing treatment “as long as we can and put our investments more toward protecting and preserving” a healthy life. Our goal, says Thea James, Associate Chief Medical Officer of Boston Medical Center, should be a system rooted in the question, “what would it take for this problem to never happen again?”

In fact, contrary to what we might think, and certainly contrary to where our dollars go, medical care itself is actually not a very strong influencer of our health, accounting for only an estimated 10 to 20% of our health outcomes. And our genetic makeup does not determine our health as much as we might think. A 2018 study in the journal Genetics found that the percentage of our longevity that’s accounted for by our genes is just 7%. In other words, the “pre-existing condition” we come into life with doesn’t make a huge difference to our overall health or lifespan. What does make a difference is how we live once we’re here.  

An estimated 80 to 90% of our health is due to what are known as social determinants of health — housing, food, education, job security. These are key levers that promote health — a critical part of the first mile of health. Focusing on the first mile means focusing on where people live, long before they start what’s called the patient journey. As Dr. Lloyd Minor, Dean of Stanford University School of Medicine, writes, our ZIP code is the single biggest predictor of our health: “It is a potent proxy for the opportunities and quality of public services available to each of us, as well as the health risks we face. Issues such as poor diet, smoking, physical fitness and air and water quality profoundly influence our health and strongly correlate to the place we call home.”

As Dean Minor told me recently at the FORTUNE Brainstorm Health Conference, moving these levers will require us to make huge changes in how we think about healthcare. “The pyramid of resources and of attention in American healthcare is inverted,” he said. “We need to be putting a lot more time and attention on prediction and prevention. Instead, we devote most of our time and attention and the vast majority of our resources to providing sick care. I’m not saying for a moment that we should take that away, but we've got to build the prediction and prevention base of the pyramid much more in America than we have in the past.”

Part of the reason why so much of our current healthcare system is focused on the last mile is because, as Dean Minor points out, public health and medicine have been drifting apart for most of the last century. And that growing gap is reflected in the massive funding gap between the two. Right now public health gets only around 2.5% of our healthcare spending. The rest — 97 cents of every healthcare dollar — goes toward sick care.

As Dr. Joshua Sharfstein, Vice Dean of Johns Hopkins’ School of Public Health, notes, if public health is working correctly, it is largely invisible — “the dog that doesn't bark.” The difference between healthcare and public health, he says, is “the difference between taking care of patients with COVID and preventing people from getting COVID in the first place.”

Switching our focus from the last to the first mile means going upstream to where people live and to how they live. “Physicians will always concentrate on the patient in front of us,” Dean Minor told me, “but we miss a vital part of our job if we don’t broaden our perspective to recognize that individual as a member of a community.”

One of my favorite examples of the benefits of community is a year-long study by researchers from Cedars-Sinai Medical Center in Los Angeles, using 52 barber shops in African-American communities as focal points for hypertension care and medication management. The results were dramatic: nearly 70% of the participants were able to achieve healthier blood pressure levels, and 90% stayed engaged for the entire year.  

A first-mile approach means not only bringing public health and medicine back together, but enlisting businesses, medical providers, government and nonprofits in the collective effort. And the good news is, that’s what’s happening. What was a slowly gathering trend before the pandemic has been fast forwarded. At Brainstorm Health, CVS Health CEO Karen Lynch talked about the $100 million investment CVS is making in “Health Zones,” modeled after “Blue Zones,” (areas of the world where people tend to live longer, healthier lives.) “What we learned with the pandemic is everything starts in the community,” Lynch told me. “We saw that with testing. We saw that with vaccines. I think we’ll continue to see more and more people focused on access to healthcare, locally… No one worries about their health if they don’t have housing, they don’t have access to healthy foods, and they don’t have a job.”

Kaiser Permanente CEO Greg Adams echoed this. “Upstream is our lane,” Adams said at Fortune Brainstorm. “We’re focused on prevention. We’re focused on keeping our communities healthy. We understand that lack of education, lack of employment, housing — all of it contributes to health — and it contributes to the excess medical costs that we have in this country.”

At Anthem, CEO Gail Boudreaux saw how taking a whole human approach to health could benefit her own workforce. To support her employees’ needs around housing, food and transportation, the company built a “Health Essentials Program” into its employee benefit system. “What we learned during the pandemic,” she said, “is that the behavioral health needs — the needs for social services, access to caregivers, all of those things — really weigh heavily on employees and impact their productivity and their ability to come to work and be their full selves, especially in an environment like this.”

Change is very gradually happening at the government level as well. The budget proposal President Biden recently sent to Congress includes increased funding for community health, home care, and $153 million for the C.D.C.’s Social Determinants of Health programs.

The first mile also means prioritizing mental health and no longer thinking of it as distinct from our physical health. When he was a medical resident in San Francisco, Dr. Jacob Berchuck saw the large shadow cast by the behavioral and social challenges his patients were facing. “When those needs were addressed with mental health treatment and social programs, I saw the incredible impact those programs had on my patients’ lives and on their general health,” he says. So he decided to do a study of 50,000 veterans who had received treatment for lung cancer by the V.A. system. The results were striking: patients who had mental health issues and who received mental health treatment, or housing or employment support, lived significantly longer than those who didn’t get that support. “If this was a pill, seeing a 30% reduction in mortality in lung cancer would be headline news,” he says.

During the pandemic, the deep interconnections between our mental health, our physical health and our emotional health have become much more apparent. And the mental health challenges that have surfaced are not going to simply go away when the pandemic ends. Commenting on a CVS Health paper on the mental health effects of the pandemic, Karen Lynch predicted we’re going to be facing a “post-traumatic COVID disorder.” This was echoed by Dean Williams, who believes that when all is said and done, “we will likely see a very much higher collateral damage to our mental health and wellness than to our physical health.”  

We can minimize that collateral damage by taking a first-mile approach in our own individual lives. “We all are worried about the future, but we want to make sure that those worries don’t develop into obsessions, anxiety and depression,” Dr. Joshua Gordon, Director of the National Institutes of Mental Health, told me. “And we know simple behavioral interventions can really help stave off that worsening.” Those interventions include sleep, meditation or conscious breathing, getting enough movement in our day, eating a diet with less sugar and processed food and making time to unplug and recharge. As the science makes clear, to improve our health and prevent us from getting sick, we don’t need to turn our lives upside down and change everything about how we live. Making even very small changes in our daily lives can, over time, lead us to a very different destination.  

The pandemic was a perfect storm where our lack of preparedness and so many of the weaknesses in our system were exposed — and the results devastating. But it can also be a perfect storm for redefining how we think about our health. We’re seeing what’s possible when we go upstream and bring together public health, community health and mental health. Creating a system more focused on the first mile can mean unprecedented progress on chronic diseases and our growing mental health crisis. If we get the first mile right, our entire journey can be transformed.

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