Heat waves can leave homes dangerously hot – even for young, healthy adults

Zoltan Nagy, Eindhoven University of Technology

Most people know that heat waves can be dangerous, but what they may not realize is that the heat indoors can be much worse than outdoors.

When the power goes out and air conditioning stops, or in homes without cooling, a house starts to function like a greenhouse during a heat wave. Heat enters through windows and walls and has nowhere to go. Air stagnates.

Within hours, indoor temperatures can climb well above what the thermometer shows outside, especially on upper floors and in rooms with south-facing windows. Over longer periods, especially if temperatures don’t cool off overnight, conditions can become lethal.

Most heat-related deaths occur indoors. When a heat dome sent temperatures soaring in the Pacific Northwest in 2021, 98% of the more than 600 deaths in British Columbia happened inside homes. Washington and Oregon also saw high numbers of deaths in homes that lacked air conditioning.

In Europe, where only 1 in 10 households have air conditioning, heat waves killed an estimated 60,000 people in 2022 and 47,000 in 2023, largely inside buildings never designed for these temperatures.

People of all ages are at risk in heat waves like these. I spent eight years at the University of Texas at Austin studying how buildings respond to extreme heat. In a recent study, my team assessed the heat risk in every single-family home in Austin.

We found that even younger, healthy adults face far more risk than they realize.

How hot is too hot for a human body?

Your body maintains a core temperature of about 98.6 degrees Fahrenheit (37 degrees Celsius). To cool down, it pushes blood to the skin and sweats. But when air temperature is high, that convective cooling weakens. When humidity is also high, sweat cannot evaporate.

If the body has no way to release heat, core temperature rises. If the core temperature increases past about 104 F (40 C), the body’s thermoregulation starts to fail. Past 109 F (42.8 C), death becomes likely.

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What makes indoor heat especially dangerous is that it does not let up at night in homes that lack air conditioning. Outdoor temperatures typically drop after sunset, and someone outside can get a few hours of recovery. But a poorly insulated home that has been absorbing heat all day releases that heat slowly, keeping indoor temperatures elevated through the night. A person inside the home never gets a break.

After two or three nights of this, even healthy people start to be at serious risk for heat-related illnesses.

Why homes heat up more than people expect

People tend to underestimate indoor heat for a few reasons.

One is that the thermostat typically sits on one wall in one room. It does not tell what the temperature is in an upstairs bedroom or near a sun-facing window. In older, underinsulated homes, the actual felt temperature can exceed 90 F (32.2 C) even when a thermostat reads 75 F (23.9 C). The hot walls, ceilings and windows can radiate heat directly onto your body.

Another reason is that people assume all homes respond to heat the same way. However, a newer home with double-pane windows and good insulation acts like a thermos, keeping heat out for a longer time. An older home with single-pane windows and cracks in the walls heats up fast.

Two houses on the same street, exposed to the same outdoor conditions, can have completely different temperatures inside. And in a blackout, where neither home has cooling, those differences can become a matter of life and death.

What we found in Austin

Our study combined two datasets. From Austin’s tax appraisal records, we pulled basic property information, such as the year the home was built, the size and the number of stories for each of the city’s 213,000 single-family homes. We then matched each home to the most similar energy simulation models in a U.S. Department of Energy database that contains thousands of detailed, physics-based building energy models representing the U.S. residential building stock.

Using those models, we simulated each building’s indoor temperatures over time during a three-day heat wave and power outage with outdoor temperatures above 110 F (43 C).

We found that 85% of homes got hot enough to pose a significant risk of death for an elderly occupant. But what surprised us was the risk to younger people.

Under today’s climate conditions in Austin, about 15% of homes already have the potential to get hot enough without air conditioning to pose serious heat risks to healthy adults. Under future warming scenarios, that number jumps to as high as 65% if average summer highs reach 104 F (40 C). Further, climate projections for Austin show that heat waves will double in frequency by the end of the century.

We found three types of buildings and accompanying risks:

• Resilient homes, which are newer and well insulated, tended to have temperature and humidity conditions that would be survivable for an elderly occupant throughout the simulated heat wave with blackout.
• Critical-risk buildings, which are mostly older homes, became dangerous almost immediately.
• And then there was the middle group – homes where temperatures rose slowly during the simulated blackout, day by day, possibly giving occupants a false sense of security until it was too late.

Texas has already seen conditions like our case study’s – a heat wave paired with a power outage. In 2024, a derecho knocked out power for nearly 900,000 Houston households while the heat index climbed to 100 F (37.8 C). Seven weeks later, Hurricane Beryl cut power to 2.6 million homes, leaving them without power for over three days, with temperatures over 90 F (32.2 C).

What you can do to stay safe

If you can’t get cooling at home, there are steps you can take that can help.

Move to the lowest floor of your home, where it will be coolest. Close the blinds and curtains on sun-facing windows. Drink water constantly to stay hydrated, which is essential for regulating body temperature.

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If you’re facing a blackout, be sure to also check on elderly neighbors, especially those living alone. You can also try to find a public cooling center; many cities now open them during heat emergencies.

Longer term, upgrades such as reflective window film, attic insulation and lighter-colored roofing can reduce how much a home heats up. After the 2021 heat dome, British Columbia’s coroner recommended updating building codes to address heat.

Our own findings point in the same direction: We propose that new homes should be required by building codes to maintain conditions in which at least light physical activity remains possible for all occupants for at least 72 hours during a power outage.

As summers get hotter with climate change and blackouts become more frequent, the risks of people suffering heat illnesses will only continue to rise.

Zoltan Nagy, Professor of Building Services, Eindhoven University of Technology

Heat waves can leave homes dangerously hot – even for young, healthy adults

This article is republished from The Conversation under a Creative Commons license. Read the original article.

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Brian N. Chin, Trinity College

“Avoid screens before bed” is one of the most common pieces of sleep advice. But what if the real problem isn’t screen time − it’s the way we use social media at night?

Sleep deprivation is one of the most widespread yet overlooked public health issues, especially among young adults and adolescents.

Despite needing eight to 10 hours of sleep, most adolescents fall short, while nearly two-thirds of young adults regularly get less than the recommended seven to nine hours.

Poor sleep isn’t just about feeling tired − it’s linked to worsened mental health, emotion regulation, memory, academic performance and even increased risk for chronic illness and early mortality.

At the same time, social media is nearly universal among young adults, with 84% using at least one platform daily. While research has long focused on screen time as the culprit for poor sleep, growing evidence suggests that how often people check social media − and how emotionally engaged they are − matters even more than how long they spend online.

As a social psychologist and sleep researcher, I study how social behaviors, including social media habits, affect sleep and well-being. Sleep isn’t just an individual behavior; it’s shaped by our social environments and relationships.

And one of the most common yet underestimated factors shaping modern sleep? How we engage with social media before bed.

Emotional investment in social media

Beyond simply measuring time spent on social media, researchers have started looking at how emotionally connected people feel to their social media use.

Some studies suggest that the way people emotionally engage with social media may have a greater impact on sleep quality than the total time they spend online.

In a 2024 study of 830 young adults, my colleagues and I examined how different types of social media engagement predicted sleep problems. We found that frequent social media visits and emotional investment were stronger predictors of poor sleep than total screen time. Additionally, presleep cognitive arousal and social comparison played a key role in linking social media engagement to sleep disruption, suggesting that social media’s effects on sleep extend beyond simple screen exposure.

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I believe these findings suggest that cutting screen time alone may not be enough − reducing how often people check social media and how emotionally connected they feel to it may be more effective in promoting healthier sleep habits.

How social media disrupts sleep

If you’ve ever struggled to fall asleep after scrolling through social media, it’s not just the screen keeping you awake. While blue light can delay melatonin production, my team’s research and that of others suggests that the way people interact with social media may play an even bigger role in sleep disruption.

Here are some of the biggest ways social media interferes with your sleep:

• Presleep arousal: Doomscrolling and emotionally charged content on social media keeps your brain in a state of heightened alertness, making it harder to relax and fall asleep. Whether it’s political debates, distressing news or even exciting personal updates, emotionally stimulating content can trigger increased cognitive and physiological arousal that delays sleep onset.
• Social comparison: Viewing idealized social media posts before bed can lead to upward social comparison, increasing stress and making it harder to sleep. People tend to compare themselves to highly curated versions of others’ lives − vacations, fitness progress, career milestones − which can lead to feelings of inadequacy and anxiety that disrupt sleep.
• Habitual checking: Social media use after lights out is a strong predictor of poor sleep, as checking notifications and scrolling before bed can quickly become an automatic habit. Studies have shown that nighttime-specific social media use, especially after lights are out, is linked to shorter sleep duration, later bedtimes and lower sleep quality. This pattern reflects bedtime procrastination, where people delay sleep despite knowing it would be better for their health and well-being.
• Fear of missing out, or FOMO: The urge to stay connected also keeps many people scrolling long past their intended bedtime, making sleep feel secondary to staying updated. Research shows that higher FOMO levels are linked to more frequent nighttime social media use and poorer sleep quality. The anticipation of new messages, posts or updates can create a sense of social pressure to stay online and reinforce the habit of delaying sleep.

Taken together, these factors make social media more than just a passive distraction − it becomes an active barrier to restful sleep. In other words, that late-night scroll isn’t harmless − it’s quietly rewiring your sleep and well-being.

How to use social media without sleep disruption

You don’t need to quit social media, but restructuring how you engage with it at night could help. Research suggests that small behavioral changes to your bedtime routine can make a significant difference in sleep quality. I suggest trying these practical, evidence-backed strategies for improving your sleep:

• Give your brain time to wind down: Avoid emotionally charged content 30 to 60 minutes before bed to help your mind relax and prepare for sleep.
• Create separation between social media and sleep: Set your phone to “Do Not Disturb” or leave it outside the bedroom to avoid the temptation of late-night checking.
• Reduce mindless scrolling: If you catch yourself endlessly refreshing, take a small, mindful pause and ask yourself: “Do I actually want to be on this app right now?”

A brief moment of awareness can help break the habit loop.

Brian N. Chin, Assistant Professor of Psychology, Trinity College

This article is republished from The Conversation under a Creative Commons license. Read the original article.

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Last Updated on July 1, 2026 by Daily News Staff

(Feature Impact) Sixty-five is more than a number. It’s a milestone. A moment to reflect on where you’ve been and look forward with confidence to what comes next. For millions of Americans, turning 65 also means unlocking one of the most valuable benefits you’ve earned: Medicare.

The best is still ahead, and it starts with knowing your options. The official source for Medicare information, Medicare.gov, is here to help with clear, trusted information.

The path to Medicare is not the same for everyone. Some people get Medicare automatically and others have to sign up. It depends on whether you are already getting Social Security. Either way, you’ll want to choose how you get your Medicare coverage.

Get information for your path at Medicare.gov, where you can find out when and how to enroll and explore your coverage options.

Understanding Your Medicare Coverage Options

When you first sign up for Medicare, you choose how to get your coverage. There are two main options: Original MedicareandMedicare Advantage.

Original Medicare is health coverage provided directly by the federal government. It has two parts:

• Part A (Hospital Insurance) covers inpatient hospital stays, skilled nursing facility care, hospice care and home health care. Most people pay no premium for Part A.
• Part B (Medical Insurance) covers doctor visits, outpatient care, preventive services (like screenings, vaccines and annual wellness visits) and durable medical equipment like wheelchairs and walkers. The standard Part B premium is $202.90 per month and is typically deducted from your Social Security check.

With Original Medicare, you can visit any doctor or hospital in the U.S. that accepts Medicare. You can also add optional coverage to help manage costs:

• Medigap (Supplemental Insurance) helps pay your share of Medicare costs.
• Part D (Prescription Drug Coverage) helps pay for medications.

Medicare Advantage is an alternative to Original Medicare that provides Part A and Part B and is offered by private insurers approved by Medicare. You still pay the Part B premium. Some plans charge an additional premium – though many carry a $0 plan premium and may even help cover part of your Part B cost. Most plans include in Part D drug coverage along with extra benefits like dental, vision and hearing. Keep in mind most plans require you to use doctors within the plan’s network.

5 Steps to Enroll with Confidence

• Use official sources. Go to Medicare.gov or call 1-800-MEDICARE for step-by-step, personalized guidance on coverage and enrollment.
• Start early. You don’t have to wait until your birthday. Explore your options now so you’re ready when your enrollment window opens.
• Know your enrollment path. Your path depends on your circumstances – some people are automatically enrolled and some are not. There are unique steps for people who are still working.
• Avoid late enrollment penalties. Missing your enrollment window can result in a permanent premium penalty for both Part B and Part D. Signing up on time protects your wallet for years to come.
• Compare plans and save. At Medicare.gov, you can compare plan costs side-by-side, based on the specific drugs you take. A quick comparison could save you money each year. You can also confirm your current doctors are in-network before you choose a plan.

Turning 65 is a milestone worth celebrating and it’s the perfect time to focus on what matters most: your health and well-being. That includes eating well, exercising and making sure you have health insurance that fits your needs. There’s no one-size-fits-all plan. What’s important is finding an option that works for you and your health and financial needs.

Start your journey at Medicare.gov – your roadmap to a healthier and confident future.

Information provided by the U.S. Department of Health and Human Services

Photos courtesy of Shutterstock

SOURCE:

Centers for Medicare & Medicaid Services

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