Mark Zuckerberg, Elon Musk, and I have at least one thing in common—a high-tech mattress pad. Excuse me, a “sleep fitness” product called the Eight Sleep. It’s really a biohacker’s version of the waterbed, with a pump attached to a cover full of capillaries that heats and cools the body—mine, plus Zuckerberg’s and Musk’s—throughout the night.
The premise: lowering your core temperature improves your sleep quality and duration. For those who’d rather not snooze outdoors or crank the air conditioning to 65 degrees, cooling the mattress is a clever solution.
As a longtime sleep obsessive, I made my first investment in the optimization category in 2013, when pregnant with my first child. At the time, the ChiliPad—a low-tech ancestor of the Eight Sleep—was the only game in town. It was nearly as loud as a 747, but the cool water that ran through its tubes helped me doze more soundly. When it stopped working, after a few years, I slipped back to my old, restless ways.
Eight Sleep, with all its advertising on the Huberman Lab and Tim Ferriss podcasts (along with endless chatter on tech-bro social media), was inevitable. The company, founded in 2015 by tech investors, is based in San Francisco. Its Web site is littered with testimonials from pro athletes, and the only thing that didn’t tempt me was its $2,500 price tag.
And then the brand sent me a tester, clearly hoping I’d do exactly what I’m doing here. It makes my old ChiliPad look as janky as Gordon Gekko’s Motorola. Who knew a water pump could be a thing of beauty? In matte black with white piping, the cover would look right at home in the Batcave.
Then there’s the tech. The product is outfitted with hundreds of sensors that track each sleeper’s heart rate, respiratory rate, sleep duration, sleep cycles, heart-rate variability (H.R.V., the variation in time between heartbeats), and even tosses and turns. (That may seem excessive, but most wearables, including the Oura Ring, do the same.)
Eight Sleep’s Autopilot software digests all of this data—along with local weather—to determine an individualized program of heating and cooling. Since no two sleepers are alike, the pod programs two zones independently. (Throuples, you’re out of luck.)
For most of us, this means getting warmer at bedtime, cooler during sleep, and gradually returning to a baseline body temperature after eight hours or so. (It will also wake you like a baby in a Snoo, with gentle vibrations.) Throughout the night, the pod makes tiny adjustments in temperature based on its exhaustive insights.
I put it to the test with two incompatible sleepers: my husband and me. He swings from sweltering to arctic to merely warm—while my temperature hovers within a few degrees of 98.6. After a month of Eight Sleep slumber, we both feel far more rested. He marvels at the comfort—so warm and toasty!—while I geek out on the data.
I’ve never denied myself the latest sleep-enhancing fad, from supplements to behavior. But nothing has supercharged me quite like the Eight Sleep. Its results were immediate: my H.R.V., which was previously averaging in the low 50s, is now hitting the high 70s. My resting heart rate has dropped from the low 50s to the mid-40s. If this all sounds unbearably dorky, and perhaps even deadly dull, then close your eyes for a few minutes. I’m going back to bed. Elon, Mark—what about you?
Ashley Baker is the Executive Editor at Air Mail Look