In the quest for optimal health and well-being, one often overlooked yet powerful tool is the exposure to morning sunlight. Dr. Andrew Huberman, a tenured professor of neurobiology and ophthalmology at Stanford University School of Medicine, has extensively discussed the benefits of this simple practice. This article, based on Dr. Huberman's insights, will explore the science behind morning light exposure and provide practical tips on how to incorporate it into your daily routine.
Morning light exposure is not a new-age concept but is deeply rooted in our physiology. Hundreds of peer-reviewed studies have shown that exposure to light early in the day is the most potent stimulus for wakefulness throughout the day and has a positive impact on your ability to fall and stay asleep at night.
The mechanism behind this involves the stimulation of melanopsin intrinsically photosensitive ganglion cells in our eyes. When these cells are exposed to light, they trigger a cascade of events in our body, including a spike in cortisol, our body's main stress hormone, which helps us feel alert and focused throughout the day
The practice of morning light exposure is straightforward. Ideally, within the first hour of waking, step outside and expose your eyes to natural light. Here are some key points to remember:
It's essential not to stare directly at the sun. While it might be safe to look towards the sun when it's low in the sky and not overly bright, caution must be exercised if the sunlight is too intense. Under no circumstances should you look at any light source that's painfully bright to your eyes. Direct and prolonged exposure to intense light can cause significant damage to the eye's retina, leading to conditions like solar retinopathy (Huberman, 2022)
For this specific practice, it's advised to avoid wearing sunglasses, as they can block the necessary light required to stimulate your eyes properly. Sunglasses are designed to filter out certain light rays, potentially decreasing the effectiveness of sunlight exposure for the eyes. However, it's worth noting that eyeglasses or contact lenses are acceptable, even if they offer UV protection. They typically don't hinder the beneficial light frequencies needed for optimal eye stimulation
The ideal duration for sunlight exposure varies depending on the weather conditions. On a clear, sunny day, a recommended target is about five minutes of sunlight exposure. However, on a cloudy day, it may be necessary to increase this time to about ten minutes due to the diffused light conditions. On heavily overcast or rainy days, where sunlight is scarce, aim for an exposure duration of 20-30 minutes. The longer duration compensates for the significantly reduced light intensity
Where you get your sunlight exposure also matters. It's recommended to get your sunlight exposure outdoors whenever possible. Attempting to gain this exposure through a window or a car windshield can significantly reduce its effectiveness. This is because most modern glass types are designed to block certain ultraviolet (UV) light rays, which are part of the light spectrum necessary to trigger the beneficial mechanisms in the eyes (Huberman, 2022).
If you wake up before the sun rises, you can turn on artificial lights in your home to help you wake up. However, once the sun is up, it's still crucial to get outside and expose your eyes to natural sunlight. Artificial lights in your home are not bright enough to stimulate the necessary physiological responses.
Conversely, at night, even a small amount of artificial light can disrupt your sleep. This asymmetry in our biology means that early in the day, we need a lot of light, but at night, even a little artificial light can disrupt our sleep.
Morning light exposure is a simple and effective tool for enhancing your wakefulness during the day and improving your sleep at night. By understanding the science behind it and incorporating it into your daily routine, you can harness the power of this natural and free resource for better health and well-being.
If you've found the power of morning light exposure intriguing and are looking to further optimise your sleep, you may also be interested in our post on effective tips for falling asleep. Harness Huberman's sleep cocktail and add it to the tool belt for good sleep.
Some light is better than none; chuck on your bright artificial indoor lights until you can make it outside for natural sunlight exposure.
There will still be plenty of sunlight available, however it'll be less intense and you'll want to stay in it for 20-30 minutes to compensate.
While lamps that simulate natural sunlight are a good substitute, nothing beats the natural morning light
Aiming for 10-20 minutes of exposure is good in most cases, however this changes depending on weather, geographic location and the individual.
Ideally you want to catch the sun within an hour of it rising, as the levels of blue light, which are key for circadian rhythm regulation, are at their highest.