Sleep Smarter

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Three important components to health: nutrition, movement (exercise), and sleep. That last one is under-appreciated, but poor sleep can have catastrophic effects on health. Also: all three aspects of health are more linked than people think. 

Sleep quality matters. You can have 8 hours of sleep, and still not get the full benefits. So the book is relevant to everyone, even if you think you don’t have problems with sleep.

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Serotonin is important. Our bodies convert it to melatonin, whose high level is key for high quality sleep.

Cortisol has been branded a devil (the stress hormone), but it’s not. It’s supposed to be at a certain level during the day. What’s a problem is too little or too much cortisol, and a bad daily rhythm.

What you want is for cortisol to be moderately high during the day, but low at night. And the other way around with melatonin. There are more important hormones that play a role here…

While our bodies are very resilient and flexible, it’s best to work together with our bodies’ natural hormone cycles, instead of working against them.


For good sleep at night, you need good light exposure during the day. It’s important for regulating the circadian rhythm.

Go outside. Even on an overcast day, there’s a lot more light than indoors. Our bodies are most receptive to sunlight early in the morning (7-8am). But even getting exposure near a window is better than nothing.

If possible, get your skin, not just eyes exposed to sunlight (for vitamin D production). Don’t wear sunglasses when not necessary.

Avoid excessive light at night. It confuses our brains. Both the amount and hue of light are important. You want small amount of reddish (warm) light.

Turn that f.lux / Night Shift know all the way to the right to minimize blue (daytime-like) light emitted. Still, it’s best to avoid screens in the last hour of the day (but we’re addicted AF).


Caffeine consumption as long as 6 hours before sleep has a negative effect on sleep length. (The half-life of caffeine in our bodies is longer than it seems…)

Adenosine is a waste product of our brains, and it signals tiredness (it’s cleaned up during sleep). Caffeine fits into adenosine receptors, blocking the sense of tiredness, but it doesn’t actually do anything. Adonesine still needs to be metabolized.

Set up a caffeine curfew: don’t drink coffee after 2pm. And limit intake to one, max two cups per day. (My tip: have a selection of non/low-caffeine teas for hot beverages later in the day.)

Caffeine is addictive and our bodies adjust to regular doses. That’s a problem, because then it loses its awesome power.

Suggestion: go 3 days on, 2 days off coffee. This way it keeps working. And go full on when needed (but not more than a few days at a time).


People think our bodies maintain a constant 36° temperature, but it’s not true. The human body is supposed to get colder during sleep, and warmer during the day.

So keep your bedroom cool. Open up the window before sleep.

20°C (68F) is prefect. Yes, really — colder than you’d think, right?

You can get a hot shower an hour or so before sleep. It’s counter-intuitive, but after the exposure to heat, your body will settle down to a lower temperature afterwards.

If needed, wear (loose fitting!) socks. Poor blood flow can keep our feet a little cold even if the rest of the body is perfect.


Going to the bed at the right time is important. Our bodies prepare hormonally for sleep in a 24-hour cycle regardless of whether you actually go to bed, and you should take advantage of that.

(Surely, you’ve experienced this, going to bed very late, and despite 8h of sleep, still feeling tired — right?)

10pm–2am are the golden hours. The best sleep occurs during that time.

So 10pm–6am is better than midnight-8am for most people, if you can do it.

Sometimes, you get a rush of energy at the end of the day, and you feel like doing things. That energy was supposed to be used for maintenance during sleep, not for you to work at night.

Sleep occurs in ~90min cycles. So 6h, 7.5h, 9h are probably better than sleep durations in between.

Night shift work has been classified as type 2 carcinogen. Fun fact: melatonin is anti-carcinogenic.

Consistency is greatly valuable.

“Catching up” on sleep doesn’t work.

If you’re going to change your sleep pattern, do it gradually, in 15min increments each day.


Habits. Seriously, stop the habit of watching TV or browsing the web in bed. What’s wrong with you? The bedroom is only for sleep (and sex), nothing else.

Sounds. You want a quiet bedroom, although some people find white noise (like waterfall sounds) helpful.

Black out. Your bedroom should be as dark as possible. If you have artificial light shining through your windows, get curtains.

Freshen up the air. To cool it down, pump more oxygen inside…

House plants. Get some! There are plants that can collect crap from the air quite efficiently.

Dress. Loose T-shirt, loose fitting pajama bottoms — or, go naked. Don’t wear close-fitting clothes at night. Don’t wear clothes that are too warm either (remember, 20°).


Your gut contains a lot of nerve tissue. 90% of serotonin in your body is actually in your gut! That’s one of many ways in which what you eat influences your sleep.

All the standard healthy eating basics:

Eat real, non-processed food for the bulk of your diet. Eat great variety of foods as well.

Some elements particularly important for sleep: selenium, calcium, omega 3 fatty acids, vitamin B, vitamin D3 (best produced by the body via sunlight exposure, but you can get high-quality supplements in the winter if you need them) — you can look up what foods are rich in those.

Magnesium. 80% of US adults are deficient in magnesium! If you need to supplement, use topical creams (magnesium can be absorbed by the skin much more efficiently than by digestion).

Supplements. Try to avoid, obviously. If necessary, 5-HTP and L-Trytophan (precursors to serotonin and melatonin) are safer than direct hormone supplementation. GABA.


Exercise is connected to sleep in a few ways:

First of all, working out breaks down your body. You get stronger only afterwards, after your body regenerates. Sleep is important for this.

Second of all, exercise can interfere with sleep, because it makes your body hot and causes it to release stress hormones.

Third of all, good sleep improves athletic performance.

For best results, work out in the morning. You can work out later too, but 4-6 hours before sleep at a minimum.

By the way. Exercise and sleep slow down the pace of telomere deterioration — literally making you live longer.

Cardio exercise does not help lose weight (See also: Why We Get Fat). Cardio is catabolic, and together with calorie restriction, it can cause your body to break down muscle to use for energy. Don’t worry, running is fine, but do it if you love it, not to lose weight. (Even if you do lose weight, you’ll just become smaller, but the same shape.)

Lift weights. It causes your body to produce a lot of anabolic hormones (to repair muscle damage). By building muscle, you will actually change your body composition and shape. And muscle burns a lot of energy (fat), too. (Women tend to be reluctant to lift weights, fearing it would make them bulky — which just isn’t true. It’s very hard to become muscular without a lot of training and/or supplementation. Everyone should do some weight lifting regularly.)


Alcohol interferes with sleep.

Yes, you usually fall asleep very quickly, but you don’t get into REM phases as much as you should.

If possible, have your last drink 2-3 hours before sleep.

Alcohol is very diuretic, so you want to drink lots of water when you drink alcohol to prevent dehydration. But do pee before bed so you don’t wake up in the middle of the night.

Also: driving while sleepy is literally just as bad as driving while drunk. Just don’t do it.


Sleeping on the back. Some people say it’s the best position, because it provides the most natural position for the spine. Just make sure that you don’t have a pillow that’s too high, or an old/bad mattress — those things will prevent healthy back shape.

Sleeping on the belly. Also fine. But lose the pillow (you don’t need it). Keep your hands and one of your legs up. Like a baby would.

Sleeping on the side. Make sure the pillow is at just the right height to support natural spine shape. Keep your arm just in front so you don’t block blood flow.


Make sure to replace your mattress at least every 7 years. Mattresses tend to lose much of their resiliency after 2 years, and then deteriorate quickly. Make sure you get a mattress that has higher than average resiliency.

Outgassing (of flame retardants and other nasty chemicals) is a potential concern.

Inner chatter

Practice meditation. We have too much stress, too many things going on in our lives, and we don’t know how to quiet down our minds. We trigger fight or flight responses too easily. Practicing mindfulness helps.

A note on earthing

Note: Sadly, in addition to lots of solid advice, the author also started preaching earthing/grounding, which is not real science. See: One. Two.

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