How to Sleep like a Caveman

Insomnia through the eyes of our ancestors with Dr. Merijn van de Laar

Counting sheep. Rain sounds. Extra-strength melatonin. There are more than a few ways we try to fight insomnia in this day and age. But there’s a question we rarely ask among all of the surefire remedies of the modern world: Have we been thinking about insomnia wrong? Travel back some 230,000 to 300,000 years, and our ancestors would probably nod their heads. While our time machine is out of commission, thankfully, Dr. Merijn van de Laar, sleep scientist extraordinaire and author of How to Sleep like a Caveman: Ancient Wisdom for a Better Night’s Rest, can help us answer that question. By combining insights from anthropology, neuroscience, and circadian biology, Dr. van de Laar helps reframe insomnia and disrupted sleep not only as dysfunctions but as adaptive traits shaped by our ancestral past. We were lucky enough to sit down with the scientist himself and chat about the challenges of sleeping in a modern society while living in bodies made for the past.

Although there was no word for it back then, how did our ancestors harness the concept of insomnia and turn it into an advantage?

What we now label as “insomnia” was often a feature, not a flaw. Based on research in contemporary hunter-gatherers, we might assume that periods of nighttime wakefulness allowed our ancestors to tend fires, keep watch for predators or rival groups, care for infants, and even socialize or problem-solve. Being awake at night increased group survival, and individuals with lighter or more fragmented sleep contributed real evolutionary value.

We’re no longer getting stalked by saber-toothed tigers during the night. Why do these instincts of nighttime wakefulness and worry still exist in humans today?

Because evolution favors survival, not comfort. The nervous system hasn’t updated at the speed of technology. Darkness, silence, and stillness were historically high-risk times, so vigilance remains wired into us, especially under stress.

How could humans today benefit from insomnia if we treated it like our ancestors — "as a feature, not a flaw," in your words?

If we treated insomnia the way our ancestors likely did, it stops being something to fight and starts becoming a signal.

Periods of night wakefulness may have once served as a natural state for heightened awareness and a possibility to check for threats around us. Based on research in contemporary tribes, wakefulness at night was probably not catastrophized. The key shift is moving from fear to neutrality. Today, anxiety about sleep often causes more harm than the wakefulness itself.  Instead of spiraling into anxiety about “not sleeping,” people could rest into that state, knowing the body isn’t broken, it’s just shifting modes, and when there is more wakefulness because of stress during the day, it is actually a body perfectly doing its job. 

When we remove fear, pressure, and urgency around sleep, reduce artificial light exposure, and align more closely with natural light-dark cycles, the nervous system settles. And when the nervous system settles, sleep often follows. In that way, insomnia becomes less of an enemy and more of a signal, and a reminder that most human brains weren't designed to be unconscious for eight uninterrupted hours, every single night. 

Explain circadian rhythm — what’s the best way to lean into it?

Circadian rhythm is your internal 24-hour clock that regulates sleep, hormones, body temperature, and metabolism. The strongest inputs are light, timing of meals, movement, and social interaction. Tracking when you naturally feel alert or sleepy (especially without alarms or caffeine) gives valuable clues to your personal rhythm.

Based on our ancestors, what are your three top recommendations for a better night’s rest, and why?

1. Anchor your day with morning light: This sets the circadian clock and was a daily constant for our ancestors.
   
2. Don't believe everything you hear or see about sleep: Modern sleep advice is often presented as rigid rules, like never wake up at night, any screen time ruins sleep, perfect sleep hygiene guarantees perfect sleep. These messages are usually well-intended but oversimplified, and they can actually increase anxiety, which is one of the biggest enemies of good sleep.
3. Normalize occasional wakefulness: Understanding that broken sleep is human can reduce stress, and paradoxically improve sleep quality.
   

Most people are strong believers in needing eight hours of sleep. What’s your rebuttal?

Eight hours as an average is ambitious and does not match general population data. Seven hours is an average, not a rule. Human sleep needs vary widely based on genetics, age, season, and life stage. Historically, sleep was flexible and sometimes even segmented. Obsessing over a fixed number can actually worsen sleep quality.

What’s your nighttime routine?

I keep evenings intentionally simple: dim lights after sunset, no stimulating conversations late at night, minimal screens, and a consistent wind-down period. I don’t force sleep. I focus on rest.

Where in the world do we still see this ancestral sleep behavior? What advantages do they have over those trying to optimize sleep in today’s world?

Most of what we know about sleep in contemporary tribes comes from research on hunter-gatherer groups in parts of Africa and South America. Sleep in Southeast Asian populations is less well studied, so the strongest evidence comes from those African and South American communities. These groups often have lower sleep anxiety, stronger circadian alignment, and more resilient sleep patterns despite shorter total sleep duration.

Their key advantages:

• Low sleep anxiety: Night awakenings and short sleep are seen as normal, not a problem.
• Strong circadian alignment: Consistent daylight exposure keeps their internal clocks stable even with fewer hours of sleep.
• Less cognitive load: Sleep supports life, instead of becoming something to optimize or control.

Bottom line: They often sleep fewer hours, but with less stress and more biological alignment, which may protect them from chronic insomnia common in modern, optimization-driven societies.