My sleep was not as lovely as it usually is — cold winds, weird noises, a mattress clearly not made for two adults and a midnight gymnast. But it got me thinking.

Sleep is a funny thing. We all do it, just like we all eat food. But not all food tastes good, and not all food is good for you. The same is true for sleep. Most of us live by one rule: get 7–8 hours a night. Check the box. Move on.

For years, that’s exactly what I did. Go to bed whenever. Try to squeeze in seven-plus hours before the alarm goes off. Good enough, right?

The latest science says otherwise. It’s not just a matter of how much you sleep — it’s when you sleep that really counts. And going to bed earlier has so many benefits that I’m now convinced of something most people would call crazy: someone who sleeps from 9pm to 3am could get more restorative sleep — and be healthier — than someone who sleeps from midnight to 8am. Six hours versus eight. But the when matters more than we ever knew.

And those warnings about screens late at night? That’s not just about doing something instead of sleeping. The science shows that bright light after dark throws off your brain’s clock — your circadian rhythm — and delays the cascade of chemical renewal your body had scheduled to begin running the moment you closed your eyes. Until you decided to halt all those lovely chemicals and doomscroll. No judgment. I’m talking to myself here too.

Here’s my sleep data below from my Whoop - my average deep sleep which it calculates as both Deep and REM and then last night. I have averaged about 4 hours/night or about 50-60% of my total sleep as DEEP + REM. A few years ago those were barely half that before a daily exercise regimen and going to bed earlier. Another thing no one talks bout is not eating after 7pm - but that's for another day.

Sleep unfolds in 90-minute cycles, but they’re not all equal. The first half of the night is dominated by deep, slow-wave sleep. The second half tilts toward REM sleep. Miss the early window and you’re disproportionately cutting into the stage your body needs most. Here’s what that early deep sleep is actually doing:

•       Releasing growth hormone. Roughly 70% of your daily growth hormone is released during slow-wave sleep — and the largest pulse comes with the very first cycle. Delay sleep, delay the surge. You’re not just missing rest. You’re missing repair and muscle growth.

•       Cleaning your brain. Your glymphatic system flushes out beta-amyloid and tau proteins during deep sleep — the very substances that accumulate in Alzheimer’s. Push your bedtime past midnight and you’re compressing exactly the window your brain needs to clean house.

•       Protecting your heart. A UK Biobank study of 103,000+ people found that falling asleep between 10–11pm had the lowest cardiovascular risk. After midnight? 25% higher risk.

•       Powering your immune system. Early sleepers had a lymphocyte ratio of 41.6% vs. 31.7% in night owls — and total sleep duration didn’t explain the difference. T cells peak during early nocturnal sleep. Delay sleep and your immune system runs on a skeleton crew.

As Dr. Matthew Walker explains, your body’s hormonal orchestra is calibrated to a schedule. Cortisol bottoms out in the evening. Melatonin surges around 7–8pm and peaks near midnight. When you fall asleep in that 9–10pm window, you’re catching the wave. 

You don’t need a sleep supplement — though I take a magnesium glycinate supplement each night. You don’t need a $3,000 mattress — though my Eight Sleep may be the greatest investment I’ve ever made in my life. What you might need is a decision about what time you put the phone down and close your eyes.

•       Be asleep by 10pm. Not just in bed — asleep. Start winding down at 9pm. The 9–10pm window aligns with your body’s natural melatonin surge and cortisol trough.

•       Protect the first 90 minutes. That first cycle is when the majority of your growth hormone releases, your brain’s waste removal kicks in, and your immune cells mobilize. It’s the most valuable sleep you’ll get all night.

•       Dim the lights by 8pm. Switching from bright, blue-rich light to dim amber lighting can extend REM sleep by 18%. Your body reads light as a clock — give it the right signal.

•       Cool the room to 65°F. Your body needs to drop its core temperature to initiate deep sleep. My Eight Sleep cools us down independently so we don’t have to worry about room temp — but yes, this is a big factor.

•       Be consistent. The UK Biobank study found that irregular sleep timing was an independent risk factor for heart disease. Your body does care when you sleep — but it cares more that you sleep at the same time every night.

•       Support tools. I can say without a doubt that I sleep better with an eye mask and ear plugs — no light, no noise.

I know what you’re thinking. 9pm? That’s early. That’s when the good shows come on. That’s when the house finally gets quiet and you get your “me time.”

I get it. I’ve been there. I’m not perfect at this. But here’s what I’ve come to believe: the hours we think we’re gaining at the end of the day, we’re borrowing from the next one. We’re borrowing from our clarity, our immunity, our hearts, and maybe even our long-term brain health.

What if the most productive thing you do today is go to bed early tonight?

-Jared

P.S. - My wife Baddie Crocker has a beautiful newsletter where she shares her perspectives on tending the land, recipes, women’s health and more. Here is her latest on how she has improved her sleep.

I write this newsletter each week because I feel my best when my body, mind and soul are all healthy. I want the same for you. If you feel like you’ve seen something valuable here, please do me a favor and forward this newsletter to a friend or let me know what you think by replying to this email or texting me - (310) 879-8441

P.S. - This newsletter does not provide medical advice. The content, such as graphics, images, text, and all other materials, is provided for reference and educational purposes only. The content is not meant to be complete or exhaustive or to be applicable to any specific individual's medical condition.

Here are links to things that have helped me improve my health:

Whoop - Track your HRV and REM Sleep

Function Health - Optimize Your Health via 160+ BioMarkers

Here are a few topics I think you’ll love if you haven’t checked them out before:

How to Breathe for Better Health

How to Supercharge Your Sleep

The Power of the Sauna

Sources

Plans, D. et al. (2021). “Accelerometer-derived sleep onset timing and cardiovascular disease incidence: a UK Biobank cohort study.” European Heart Journal — Digital Health, 2(4), 658–666.

Van Cauter, E. et al. (1996). “Physiology of growth hormone secretion during sleep.” Journal of Pediatrics, 128(5 Pt 2), S32–S37.

Besedovsky, L. et al. (2012). “Sleep and immune function.” Pflügers Archiv, 463(1), 121–137.

Nakamura, Y. et al. (2010). “Those with the habit of going to sleep early show a higher ratio of lymphocytes.” Stress, 13(6), 536–540.

Nedergaard, M. et al. (2024). “The glymphatic system clears amyloid beta and tau from brain to plasma in humans.” Nature Communications.

Walker, M. (2017). Why We Sleep