Can We Grow Old in a Hotter World?

I am writing this from Italy, where the heat this summer has been impossible to ignore.

Although extreme heat is a major public health challenge across the globe, Europe is on the frontline, warming faster than any other continent. Heat is often described as a silent killer. Unlike floods, fires, or storms, its effects are less visible but no less deadly. Extreme heat can trigger sudden illness and cause chronic conditions such as cardiovascular, respiratory, and kidney disease to worsen rapidly. [Link]

And heat does not affect everyone equally.

Older adults, people living with chronic illness, those with limited financial resources, and those who are socially isolated are often the most vulnerable. [Link]

This should make us pause.

We invest enormous resources in healthcare, prevention, and research to reduce multi-morbidity and mortality in later life. Yet every summer, many thousands of older adults still die from a largely preventable risk: extreme heat. Heat-related deaths exceeded 60,000 in Europe in 2022, and 2024 became one of the deadliest summers on record, with nearly 63,000 estimated deaths, including around 19,000 in Italy. [Link]

Climate change is becoming a longevity issue, not just an environmental one.

This feels personal to me.

Long before working in global health and healthy aging, I spent years in environmental advocacy, including serving as director general of Greenpeace Italy. Environmental issues have long been close to my heart, but today I increasingly see them through another lens: aging.

I think about this when I look at my parents in Florence.

They do not have air conditioning. For decades, they managed summer the traditional way: closing shutters during the hottest hours, creating airflow through the house, using fans, relying on light cotton or linen bedding, and planning activities around the cooler hours of the day.

Florentine summers were always hot and humid, with little breeze, but manageable.

Over the years, both the climate and the challenge of adapting have changed.

My parents are still active and in pretty good health, yet I see how their margin of resilience has narrowed. The strategies that worked for decades no longer seem sufficient. The house stays hot longer. The air feels heavier. Even walking outside to run simple errands becomes difficult during large parts of the day.

Adaptation is not only an economic issue, although cooling systems can be expensive. It is also about capacity.

As we age, even starting a major home renovation, installing air conditioning, improving insulation, or redesigning living spaces can feel overwhelming. Not everyone has the option to move somewhere cooler or spend the hottest months by the sea.

Solutions do exist. Some cities are beginning to adapt through cooling infrastructure and smarter urban design. Paris, for example, has invested in district cooling systems, while other cities are expanding green spaces, shade, and reflective surfaces to reduce heat exposure. [Link]

When we talk about longevity, we often focus on individual behaviors: eating better, moving more, and sleeping well.

These matter enormously.

If we are serious about promoting longevity, healthy behaviors alone are not enough. Just as we care about reducing pollution and improving the environments in which we live, we must also stop treating climate change as a distant or abstract problem. It is increasingly shaping how we live, how we age, and, too often, how we die.