The Nuance

‘Respiratory discipline’ can activate your most potent anti-stress system

Photo: Lorenzo Fattò Offidani/Unsplash

Your body reacts to stress in a number of well-mapped ways. Heart rate and blood pressure speed up, muscles tense, digestion slows, and breathing becomes clipped and rapid.

All of this happens because your brain has registered the presence of some sort of threat. Whether physical or psychological, this threat triggers a trickle (or a gush) of adrenaline, noradrenaline, and other stress-related hormones. These chemical messengers shift the activity of your nervous and immune systems in ways that are meant to help you either flee from danger or weather some kind of ordeal or confrontation.

None of this tends to…

The Nuance

Attention fatigue is a threat to your cognitive and mental health

Photo: Myles Tan/Unsplash

Imagine shining a flashlight at a wall in a dark, empty room.

If you walk toward the wall, the light will contract. The closer you get to the wall, the smaller and more concentrated the beam of light becomes. By the time the flashlight is an inch from the wall, you’ll see a tight, bright circle of light surrounded by shadow and darkness.

Your attention is a lot like the beam of that flashlight. You can focus it closely and intensely on something, or you can relax it — allowing it to grow soft and diffuse.

A lot of research…

The longer the wider world remains unvaccinated, the greater the risk that a devastating new variant will emerge

Photo by Yolanda Sun on Unsplash

In a letter recently obtained by The Guardian newspaper, more than 100 former presidents and heads of state urged the leaders of the world’s wealthiest countries to do much more — to commit more money, in particular, but also more aid and resources — toward making and distributing vaccines across the globe.

“No one anywhere is safe from Covid-19 until everyone is safe everywhere,” the letter’s signatories wrote, according to The Guardian.

That’s not just lofty talk, and it’s not just a plea for the sake of the unvaccinated. That is cold reality.

Apart from the deadly threat that the…

The Nuance

Few of us fully appreciate the role of social comparison in our well-being

Photo by Marcel Strauß on Unsplash

For a 2012 study in PLOS One, researchers invited a young woman into a laboratory at Ohio University.

The woman learned that she would be taking part in an “aesthetic judgment” experiment. The researchers took a photograph of her face and then asked her to sit at a table that held two objects: a computer monitor and a mirror.

On the monitor, the woman viewed a series of headshots of what the study termed “attractive professional models” — all of them women. Following this barrage of beautiful faces, the woman’s own photograph appeared on the screen. But it wasn’t just…

The Nuance

Ultra-sterile living conditions may contribute to common astronaut illnesses, including gut, skin, and immune-system problems

Photo: NASA/Unsplash

Spaceflight is hard on the human body. The absence of gravity can induce a form of nauseating motion sickness known as space adaptation syndrome. As time passes, weightlessness can also cause muscle wasting, bone deterioration, and other health problems.

NASA and its sister space agencies around the world have long recognized these health threats, and they’ve developed effective countermeasures. But as they’ve learned to manage the challenges of zero-gravity environments, other concerns have emerged.

According to a 2016 NASA-led study in the International Journal of General Medicine, time spent in space rapidly perturbs the human immune system. Nearly every molecule…

Good Question

New research intensifies the debate

Photo: Promodhya Abeysekara/Unsplash

Americans are inveterate snackers.

More than 90% of the U.S. population eats at least one snack a day, and most of us eat several. Some experts have called snacking “a hallmark of the American dietary pattern.”

Our enthusiasm for snacking isn’t new. Between the early 1970s and the late 2000s, the average number of snacks we consumed hardly budged; we ate two or three snacks a day back then, and that’s about how many we eat now.

While we may not be snacking more frequently than we used to, there’s some evidence that our snacks have gotten bigger.

Measured in…

The Nuance

Roughing it now and then may be the secret to a more contented life

Photo: Anna Kubiak/Unsplash

The journalist Michael Easter once spent a month in the Arctic Circle, tracking a herd of caribou for a national magazine story.

After 33 days in the backcountry — lugging an 80-pound pack through forests and tundra, spending each night outdoors in a tent — Easter says that his reunion with running water almost brought him to tears.

“I was in this little bathroom at an airfield in Kotzebue, Alaska,” he recalls. “When that warm water hit my face, it was like, oh my god. I think I let it run over my hands for about 20 minutes.”

In his…

Good Question

‘Poignant’ media may help us find answers to life’s big questions

Photo by Jace & Afsoon on Unsplash

On my 13th or 14th birthday, I can’t remember which, my dad gave me a boombox and some CDs.

The CDs were Neil Young’s Harvest, and greatest-hits collections from the Grateful Dead, Jefferson Airplane, and the Steve Miller Band. He told me he’d picked these because they were some of his old favorites — part of the soundtrack of his life in the late 1960s and ’70s when he’d lived in Northern California and Oregon. Even before I’d listened to them, I liked them because he liked them.

I especially liked the Neil Young. It hooked me from the first…

The Nuance

Exploring the science — and lack thereof — behind sunscreen safety

An illustration of a generic blue bottle with a “sun” shaped icon, set against a bright yellow background, centered on the shape of a sun.
An illustration of a generic blue bottle with a “sun” shaped icon, set against a bright yellow background, centered on the shape of a sun.
Kieran Blakey for Elemental

For a 2019 study, researchers at the U.S. Food and Drug Administration had healthy people apply common, commercially available sunscreens.

For four days — and four times each day — the people in the study sprayed or rubbed sunscreen onto their bodies. Most sunscreen labels advise people to reapply “at least every two hours,” so the study was designed to assess what would happen inside the body if people followed this guidance. For example, if someone went on a beach vacation and slathered on sunscreen throughout the day, as directed, what, if anything, might show up in their blood?



Probably. But first, consider the risks.

Photo illustration: Save As/Medium; Source: Karsten Jipp/EyeEm/Getty Images

The internet makes quite a fuss about the ways we arrange our bodies in repose.

Googling “best sleep position” turns up a cool 765 million results, and some of the top hits maintain that how you sleep — back, stomach, left or right side, fetal — has profound implications for your spine, heart, breathing, appearance, and much else. There’s even some Freudian pseudoscience linking certain sleep positions to personality traits, which seems to have about as much solid scientific backing as palmistry.

All of these claims are somewhat confounded by the fact that we all tend to sleep in a…

Markham Heid

I write about health and science. I live in Detroit with my wife and kids. I’m trying to learn German, but my progress so far is nicht gut.

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