Okay, folks. We have to stop using the "Evolutionarily, we didn't have X so X must not be a good idea."

This is not sound scientific reasoning.

Evolutionarily (if that's even a word) we didn't have toilet paper, bicycles, or toothbrushes.

But I think they're a good idea. Pillows are, too.

If you sleep on your back or side, you need a pillow. Period. If you sleep on your stomach, you are turning your head to one side for almost a third of your life. This causes muscle imbalance and pain down the road. Paleo is not a re-enactment. Use a pillow.

In Esther Gokhale's book she recommends using a pillow (placed under the shoulders all the way up to the head) and her posture method is based on looking at traditional cultures around the world. I would look up the Authors@Google video of her talk.

Researching the sleep habits of most cultures, I've come to conclude that sleeping a full 8 hours over night with no naps is a relatively recent, industrial revolution type phenomenon. Many cultures are biphasic and the sleep habits of hunter-gatherer cultures like the !Kung are polyphasic. Having shorter sleeps might help with your stiffening up.

I don't think we know what we did evolutionarily. If Grok had animal skins, he could have stuffed one under his head. Might have to wait for science to answer this one. I have looked and looked for good data on this kind of thing, ie the healthiest sleeping positions and types of bedding, but have found it rather sparse. So far, all I have heard have been advertisements for products and theories with a bit of logic but no real scientific data backing them. -Eva

I sleep on my side always so MUST have a pillow between my knees. Otherwise, I wake up feeling like my hips have caved in. I don't actually really use a pillow for my head (not on purpose- I just only have one pillow, and it ends up between my knees), but I use my upper arm for a pillow, so it's pretty much functioning in the exact same way. Through this self testing of pillowlessness, I have also found that if I move around off my side, I just end up using various parts (arm, shoulder, neck) of my partner as a pillow. So, in my opinion? Ain't nothing wrong with a pillow.

After reading an article on instinctual sleep habits of primitive tribes cited by Marc Sisson's Daily Apple, I gave up my favorite buckwheat husk pillow and have never slept better. I no longer have the problems with my neck and shoulders that plagued me when I tried all types of pillows through the years.

I wonder what chimps do, since they're anatomically similar. Web pages I've seen talk about "curling up in a nest". That would seem to imply sleeping on their side but what else?

If I sleep on my stomach, I can get away with minimal/no pillow, but lately I've been sleeping on my side, so a pillow is almost a necessity.

I just recently stopped sleeping without a pillow and I no longer get the neck pain that ran up the back of my head. My pillow also made me hot. I have had pillows from $3 to the $70 My Pillow. All horrible. One thing I do is put an empty pillowcase where my head goes to keep the sheets cleaner. Also, if I place my hand under my neck when I sleep on my side, I slide it under the pillowcase. It's more comfortable. I only discovered sleeping without a pillow a few weeks ago, but so far, so good.

I stopped sleeping with a pillow (lying flat on my back) and it definitely helped with lessening those little aches and pains in my neck that I used to wake up with sometimes. I still use a pillow when I sleep on my side though to keep the neck in alignment.

I also tend to transfer myself to the floor in the middle of the night. Again, sleeping on my back, it keeps my shoulders from hunching forward (my mattress is too soft). I sleep best with a bit of padding on the floor, like a down comforter, underneath me.

You know, when I visited South Korea I slept on a giant stone bed with a 1 inch thick cotton pad under me for two weeks. I got used to it very quickly (although I could sleep just about anywhere). In my two weeks there, I lost about 5-7 lbs. My two theories are that I burned more calories through the night sleeping on a hard surface and that the diet there was pretty awesome. Aside from the white rice, the food could definitely be characterized as paleo-- fantastic fish, meats, shellfish, pickled veggies.

I think it's fine with or without a pillow based on what's comfortable for you. From pictues, I know that some people who go without pillows sleep on their side with their head on their upper arm.

I've had a cervical fusion and it's painful to sleep without a pillow. I can rest my head on my upper arm, but the arm soon protests the weight. And, I like to sleep with one knee sharply bent and on my side but leaning over toward the bent knee.

I use buckwheat pillows. I didn't like them until I realized the duh! that they are hard if pushed down from above but fluffy and mold-able when lifted from below. Ahh, that felt so good once I figured out how to create a low-but-perfectly-shaped buckwheat resting place.

I get 6-7 hours of restful sleep.

I sleep with a contour pillow. I find that sleeping without a pillow gives no support to my neck at all and sleeping with a regular pillow puts my neck in too high of a position. I have heard that when sleeping you want to keep the neck in alignment with the spine, so some sort of a pillow is necessary.

recently i was having some soreness on the back of my neck and head and found that my pillow was exacerbating it, (and it is one of these ergonomic, relatively low wool pillows) so i took the pillow out and it feels much better. now i sleep half and half with and w/o a pillow, sometimes i wake up in the night and grab it. if i am sleeping on my back i definitely go without it, and i'd probably go with it if on my side. stomach, i'm not sure which, i think it's more of a toss up.

but i was glad this was something i figured out worked for me, not something i did because it was recommended to me. though i have pondered the health of sleeping with/without a pillow before. i had tried it before and just couldn't get comfortable, but now it really works for me.

it seems most of us have problems sticking our heads out in front of us, when we should keep it aligned with our spine. so going without a pillow, at least while sleeping on your back, seems natural. though when on your side, it might be better to use one.