Eight Sleep Pod & Cover - Why I returned it

This week has been punctuated by two entirely separate and yet equally frustrating streams.


As a nerd, and someone that was deeply involved in the biohacking space for a few years, my OCD has enjoyed trying to optimize unnecessary parts of my life. In particular, as someone who has always struggled to fall asleep and suffered occasional bouts of insomnia sleep has been a fun target.

It started with some melatonin, moved through lamps, screen filters, blue light glasses and more.

After having kids, I quickly realized that all of this effort is for nought. When you’ve got random interruptions every night thanks to hunger, thirst, bad dreams, wet beds and sickness, parenting humbles you into realizing that when you’re tired enough you’re going to sleep.

However, for the better part of a decade I’ve been aware of Eight Sleep and have always been curious. Their product essentially adds a capillary network of tiny tubes to put a small layer of water between you and the mattress. The tubes are then hooked up to a pump and heating controller to precisely control your body temperature. In principle, you would expect it to keep you warm in winter, cool in summer.

In recent generations Eight Sleep have joined the artificial intelligence bandwagon and their new stuff includes a bunch of motion sensors that are good enough to detect movement breathing and heart rate. Putting a thin layer of intelligence on top, allows your bed to be warm when you get in, but cool as soon as you fall asleep.

In principle, there’s some research that says our sleep is best when it follows what you’d expect from sleeping outside or near a fire. Cool around midnight with a gentle ramp up of temperature near dawn.

I had been curious about the experience for the longest time but the significant price tag had always been enough to stop me dead. I mean, seriously, $3,500 for essentially a fancy blanket is pretty steep. Oh and did I mention, that “AI” to get variable temperatures through the night is a $200/year subscription?

However, with most of my debt paid down at this point and a tax refund on the horizon, I looked at it again with a “why not?”. I deserve it, and given the recent exhaustion any little help would be appreciated.

Night 1

Terrible. Noisy - like having an old fan in the room. No appreciable temperature difference.

Setting the temperature to +10 (ensure if this a relative scale or an actual temperature, which is probably isn’t, because is that Celsius or Fahrenheit), after making noise all night was barely struggling to get to +2 in the app.

I figured that the “3 hour” purge process that allegedly completed in under 10 minutes probably didn’t get any water into the mattress.

Running the purge again the morning required adding another 3 litres of water. Yeahhhhhh…

Night 2

Woke up around 2 AM, couldn’t get back to sleep, feet are blocks of ice

Night 3

With giant wooly socks on, climb into bed, a second blanket on my legs.

Wake up around 3 AM with cramp in my calf. Need to dig into the app to turn the cover up.

Night 4

Cramp again.

This is annoying. And the bed is too cold for the constant interruptions of the kids. After sorting the kids out I can’t fall asleep again when I’m at the point of nearly shivering. Why doesn’t the “AI” rest to warm when I’ve clearly gotten out of bed?

Night 5

Finally dial in a temperature to avoid cramp. However now my torso is waaaay too hot. This is ridiculous. I’m wearing thick wool socks, with 2 big blankets on my legs whilst I’m shirtless and uncovered on my top half.

Meanwhile the wife has decided she doesn’t like and has just disabled her side of the bed.


Clearly this isn’t working for us, but I’m sort of stuck in a sunk cost fallacy. Something this expensive (with a decade of anticipation) can’t be this stupid or underwhelming. Of course it’s not helped that when you look at YouTube and online reviews it seems like this is the thing that’s going to cure cancer and world hunger. In retrospect, I wonder how many of these are paid reviews, but aren’t labelled as such.

Nevertheless I stick with it for another week, slowly tweaking the temperature at different times of night, but I keep hitting the same problems.

It really is nice to get into a warm bed. It feels like when you get out of bed in winter and then climb back in and find “the warm patch” - but now the warm patch is the whole bed.

Sleep stats

Looking at my long term sleep stats, I saw no real notable difference in amount of deep sleep or REM. No difference in resting heart rate or breathing. No difference in heart rate variability.

If I squint, I maybe fell asleep faster, but I could equally chalk that up to a hard week at work.

Short of taking some blood tests to see my cortisol, I can’t say I saw any difference.

Alarm functionality

The pod comes with a feature, where the temperature rapidly ramps up just before an alarm. The cover then has a little motor around your shoulder blades for the alarm.

The heating feature was really nice, it nicely simulated the sun coming up and you then being too hot to keep sleeping.

It worked for 2 days. After that my body completely adapted and ignored it.

The motor feels like a bad vibrator and not at all like someone tapping you. It is waaay too loud, and will definitely wake your partner, and much too weak if you’re deep.

None of the alarm features self cancel if you get out of bed. So if you’re like me and keep your phone out of your bedroom, the thing just keeps buzzing and heating indefinitely.



We didn’t make it to the end of the 30 day “complete satisfaction” thing. We were done.

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