Taking Andrew Huberman's advice on morning sunlight exposure

20 Feb

Why is morning sunlight important and how can it help improve your sleep that night? Learn more by watching the video above.

Earthy30 is the nutritional challenge that helps you eat 30 different plant-based foods a week while integrating lifestyle tips to improve your longevity and healthspan.

This week it’s about optimising sleep through the mechanism of morning sunlight exposure. If you’re a Huberman fan, as I am, there’s an additional nugget in here for you as we explore the Light Meter app and how to read lux.

We’ll answer the question, “How much weaker is the light in the centre of the room, vs near the window?” and “How much brighter is it inside the window vs outside the window?” Surely the same right - glass is clear after all? Not so, and Light Meter is going to show us! After this vlog, you’ll definitely want to work nearer a window - or outside - and never want to work in an underground bunker of an office ever again!

I’m name dropping Huberman as he talks a lot about the effects of morning sunlight on circadian rhythm and sleep. But you can also hear sleep expert Matthew Walker talk about this or read additional research from Wright et al., 2013 on how camping can advance your body clock vs. being exposed to ‘electrical light’.

Why is morning sunlight important?

Morning sunlight exposure helps kick off the ‘waking’ part of your circadian rhythm while setting a 16 hour timer for the ‘night’ part, where you fall asleep.

Hubermam talks about getting sunlight into your eyes first thing in the morning to kick off your ‘wakeful’ part of your circadian rhythm, as a way to compound the effects of the natural spike of cortisol that humans get every morning.

Huberman goes on to explain how the eyes are an extension of the brian, and have sensory capabilities as well as ‘seeing’ capabilities. Beyond processing images, the eyes and brain look for faces we recognise, they examine the relative velocity of objects coming towards us, and they sense light! It turns out that even blind people should get morning sunlight to help set their body clock, even if they can’t form images through sight.

In the morning, what the eye is looking for is the intensity of the light and the colour too. Each day, as the sun passes over us, the light we see changes. It starts off more ‘orangey’, turns to blue and back to orange. What tells the eye that it’s morning or evening is the ratio of these colours. If there is orange and blue, it’s either morning or evening.

This light in the morning helps you wake up and set the sleep timer for 16 hours. In the evening, it offers another nudge towards bedtime while dialling down the sensitivity of the eye to light thereafter - handy if you need to be on the laptop after dark.

Going outside to get your morning sunlight

According to Huberman and others, you have to go outside to get your morning light. Being inside just won’t cut it. And in this video, we’ll be showing you why using Light Meter.

Light Meter measures lux, which is the intensity of light. 1 lux is how much light 1 candle projects onto a surface a metre square, one metre away.

Before you can use it, you need to make a diffuser, which is that bit of paper across the top of the phone, held on by the clothes peg!

In the video, you can see indoors is 370 lux.

Inside the window is 1400 lux.

Outside the window is 3000 - 9000 lux.

The window is about 4 times brighter than the middle of the room with the lights on.

Outside, on this day, is at least twice as bright the other side of the glass, but maybe 6 times brighter a metre away from the building, and likely much brighter if the sun was in line of sight.

This is why you need to be outside and not getting your light through a window or car windscreen.

When is the best time of day to get sunlight?

You need to see sunlight in the morning. There are two reasons for this:

1—You need to catch the orange/blue contrast in the light to signal to your brain that it’s morning and not just ‘day’.

2—You want to align it to your healthy cortisol spike that kicks off a bunch of other hormonal changes that get your body ready for action.

Fun experiments with Light Meter

Off the back of Huberman’s endorsement I took the Olympic Park in London with Light Meter.

On an overcast day, outside of my window I got 7,300 lux. Cloudy, but way way way brighter than just being indoors. On these days Huberman recommends being outdoors for 30 mins!

Near the velodrome, on a cloudy day with sun breaking through, you can see 11,100 lux.

An even brighter, cloud day, 20,000 lux.

Sunny day, 61,000 lux.

And on the ski slopes, 159,000 lux.

See those photos here.

Head over to our challenge page and build a better you and thank you Andrew Huberman for your inspiring content.