Articles
Recent Blog Posts
Best Sleep Position for a Stuffy Nose: What Airflow Studies Show
A stuffy nose that is fine all day and blocked the moment you lie down is not in your head. Lying flat does change the inside of your nose, and rhinology labs have been measuring it with pressure gauges and sound probes since the 1960s. What they found is more useful...
Sleep Positions for Better Breathing: Which Side, Head, and Tilt
"Sleep on your side" is the standard advice for breathing better at night, and it is mostly right. It also leaves three practical questions hanging. Does it matter which side? Is it your body that has to turn, or would turning your head be enough? And if you prop...
Does a Regular Bedtime Matter for Kids? What 10,000 Children Showed
The old version of this page made one claim with a study behind it: "children with irregular bedtimes are more likely to experience behavioral issues." That is true as far as it goes. It traces back to a single British study that followed more than 10,000 children,...
Revenge Bedtime Procrastination: Why We Stay Up, Measured
"Revenge bedtime procrastination" is a phrase from social media, not from a lab. The research name for it is plainer: bedtime procrastination, defined in 2014 as going to bed later than you meant to when nothing outside you is stopping you. The "revenge" part adds a...
Sleeping on Your Back: Who Does It, and What the Studies Found
Back sleeping has a good reputation. The old version of this page called it "the optimal choice" and credited it with spinal alignment, less pain, less inflammation, clearer sinuses and better skin. That is a long list for one position, so I went looking for the...
How to Sleep on a Plane: What Lab Tests Found About Seats, Drinks and Noise
Most advice about sleeping on a plane is about gear: the right neck pillow, the right headphones, the right seat. Very little of it has been tested on passengers. When I looked for studies that measured how much people sleep in an economy seat, I found none. Every...
Box Breathing for Sleep: What the One Trial That Tracked It Found
Box breathing is simple enough to explain in one line: breathe in for four, hold for four, breathe out for four, hold for four, repeat. It is said to calm the nervous system, to be used by Navy SEALs, and, on a lot of sleep sites, to deepen sleep. The first claim has...
Light While You Sleep: How Dark Does Your Bedroom Need to Be?
In a study published in 2022, a sleep lab at Northwestern University put 20 healthy young adults to bed, and on the second night, for half of them, left the overhead lights on: four 60-watt bulbs in the ceiling, set to give 100 lux in the room. The next morning the...
Insomnia in Women: Why Reports and Sleep Lab Results Disagree
Women report insomnia more often than men in almost every survey ever run on the subject. That part is not in doubt. The odd part shows up when you wire people to a sleep lab's sensors overnight: on the recordings, women usually sleep as well as men or better, with...
Natural Light and Your Body Clock: How Much, and Does a Window Count?
In 1994 a team in San Diego, one of the sunniest cities in the United States, clipped light meters onto 106 middle-aged adults and let them go about their lives. The median person spent just 4% of the time they were observed in light of 1,000 lux or more. That works...
Sleep Anxiety: Why Trying Harder to Sleep Backfires
Sleep anxiety is the dread that starts before you even get into bed: the math about how many hours are left, the certainty that tonight will be bad too, the effort of lying very still and trying hard to drift off. That last part is the trap. Sleep is one of the few...
Nightmares vs Night Terrors: How to Tell Them Apart by the Clock
A child who screams at 10:30 p.m., stares straight through you, and has no idea anything happened by breakfast has almost certainly not had a nightmare. A child who pads into your room at 4 a.m., wide awake and able to tell you about the dog that chased them, almost...