The question was simple. I asked it of twelve board-certified sleep specialists over the course of three months, in person, by phone, and once, memorably, in a Zoom call at 11 p.m. their time.

Here it is: If you could only recommend one habit to a generally healthy adult who wanted to sleep better, what would it be?

I expected the answers to converge on something. They did, but not on what I expected. They did not, for the record, converge on melatonin, on magnesium, on a particular mattress, on a meditation app, on a mouth tape, on a weighted blanket, on a cold plunge, on any supplement I had ever heard of. What they converged on was, in retrospect, obvious.

The neurologists (6)

Five of the six neurologists I spoke with said, within thirty seconds of being asked, the same word: consistency. The sixth said "a regular wake time," and then expanded: "If you do nothing else, pick a wake time and hold it, even on weekends, even after a bad night. The wake time is the anchor. Everything else hangs off it."

One of them — a sleep neurologist at a major teaching hospital who asked not to be named — put it more bluntly. "The biggest single thing I tell patients is: stop moving your wake time around. The body wants a phase. Give it one. Most of what we call insomnia is just a body that's been told it has no idea when morning is."

The pediatricians (3)

The pediatric sleep specialists said something slightly different. They emphasized the bedroom — not the bed, the room. "I tell parents: the bedroom is for sleeping. That's it. Not for screens, not for scrolling, not for laptops, not for television. The bedroom is for sleep. When you use it for other things, you train your brain to be awake in the place where it should be asleep."

All three of them said this almost word-for-word. It is, apparently, the single most repeated piece of advice in pediatric sleep medicine.

The surprise

Of the twelve answers I collected, eight involved some version of light. Not supplements. Not mattresses. Not even temperature. Light. Three of the neurologists specifically mentioned morning light — the kind you get from a sunrise alarm, or a window, or a five-minute walk. The psychiatrists mentioned dim light in the evening. The dentist, somewhat to my surprise, mentioned blue light specifically: "I tell my patients the same thing my ophthalmologist tells me: no phones in bed. None. The light is the problem, but the habit is the easier thing to fix."

"Eight of twelve sleep specialists, asked the same question, said the same thing: light. Not melatonin. Not meditation. Light."

What to do with this

I'm not a sleep doctor. I am a writer who has been testing small sleep devices for the past year and has developed an opinion about them. The opinion is: the boring things work. A consistent wake time. A bedroom with no phone. Morning light. The expensive, app-connected, vibrating, temperature-controlled bed you saw advertised last week will not move the needle as much as those three things, which cost nothing.

That said — if you want a small, friendly nudge toward the morning-light habit, the Dreamegg Sunrise Beam is what we use. It is not a magic device. It is a slightly fancier way of doing the boring, free thing that eight of twelve specialists said was the most important thing to do.

Methodology: Twelve board-certified physicians, all with active sleep medicine practices, interviewed by phone or video between September 2024 and December 2024. Not a scientific sample. Quoted with permission unless otherwise noted.