Ten Minutes of Morning Sun

The cheapest, most reliable upgrade to my day costs nothing and takes ten minutes: I get outside into the morning sun. Every day. Before the phone, before email, before anything else.

It isn’t a supplement or a gadget. It’s the oldest signal there is — daylight hitting your eyes early — and it does more to set your energy, mood, and sleep than most things you can buy.

What morning light actually does

Light entering your eyes in the morning suppresses melatonin — the “it’s night” hormone — and helps trigger the cortisol awakening response, the normal morning cortisol rise that makes you alert and sets the day’s autonomic tone. Cortisol gets a bad reputation, but in the morning it’s *supposed* to spike. Timing is the whole point. (Huberman Lab.)

It also starts a countdown. Roughly 12–16 hours after that light signal, melatonin begins rising again to bring on sleep. So morning light is, in a real sense, about *tonight’s* sleep — you’re setting the timer at breakfast. (Huberman Lab.)

And it isn’t only the morning dose. The brain tracks cumulative bright light across the whole day, and more daytime brightness produces a sharper, earlier evening melatonin rise. Light also supports serotonin activity tied to mood, while chronic circadian disruption is an independent risk factor for depression. The signal is upstream of a lot.

Why it has to be outside

The difference is intensity. A bright indoor office is around 300–500 lux. Outdoor light is roughly 10,000–25,000 lux even under cloud — on the order of 20 to 80 times brighter. Your circadian system needs that intensity to actually set the clock.

Which is why sitting next to a sunny window doesn’t do the job: the light reaching your eyes is far weaker, and glass blocks UVB (so no vitamin D through the window either). If the goal is setting the clock, you go outside.

How I do it: eyes open, facing the general direction of the sky, never staring at the sun. No sunglasses for those few minutes — a hat is fine. Direct sun on skin does a separate job, vitamin D, which wants roughly 5–30 minutes of skin exposure depending on conditions. That’s a bonus, not the main event.

The dose

Get it as close to waking as you can — ideally within the first 30–60 minutes, and try not to push past the first hour or two. Weaker light just means stay out a little longer:

That’s the entire protocol. Get outside, do it early, stay longer when the light is weak. No app required.

My one-hour morning bootstrap

Most mornings I go down to my building’s pool and run the same sequence: 20 minutes of sun, 20 minutes swimming, 20 minutes in the sauna. About an hour to bootstrap the system — light, movement, and heat, in that order.

The sun is the timing signal. The swim gets the body moving and the blood up. The sauna adds heat and a hard reset. Together they draw a clean line between “asleep” and “on” — so by the time the day starts competing for my attention, the system is already booted.

The no-excuses floor

Not every morning has a spare hour. On a busy day the whole thing collapses to one move: I take my coffee outside and sit in the sun for ten minutes. That’s the floor.

Ten minutes is short enough to fit any morning and long enough to cover a sunny-day dose. No gear, no setup, nothing to buy — it’s bolted onto something I already do: wake up and drink coffee. Everyone has ten minutes, which is exactly the point: the single best free input to your day is also the easiest.

Start the day at the top

Morning sun isn’t a dramatic biohack, and that’s exactly why it works as a foundation: it’s free, it’s daily, and it compounds. Melatonin down, cortisol up, tonight’s sleep timer already running — all from stepping outside.

Get out early. Let the light reach your eyes. Do it again tomorrow.