Using Light for Optimal Physical and Mental Health
Using Light for Optimal Physical and Mental Health
Light has a massive overall impact on our physical and mental health and overall well-being.
It directly impacts our sleep, mood, focus, hormone levels, immune system, and distress tolerance (our ability to cope with stress), and determines whether we wake up feeling groggy or refreshed.
The good news?
Most light exposure strategies are zero-cost.
Here are the 8 most important light-based tools to optimize your health, well-being, and performance.
(Psst… if you want to maximize the benefits while minimizing the time investment required, Tools #1 and #4 are the most important.)
Tool #1: Use Morning Sunlight to Set Your Mind and Body Right
Stanford neuroscientist Dr. Andrew Huberman considers viewing morning sunlight as one of the top 5 critical actions for peak physical and mental health and performance.
Sleep
Movement
Nutrients (Macro and Micro)
(Sun)Light
Relationships
Viewing morning sunlight as soon as you can after waking, ideally within the first few hours of your day, delivers a host of positive benefits.
Prepares the body for sleep later that night.
Increases early-day cortisol release which is the ideal time for elevated cortisol.
Strengthens your immune system, metabolism, and ability to focus during the day.
Helps regulate your circadian clock which is how the body anticipates when to wake up and go to sleep and manages other biological processes like hunger and body temperature.
The Morning Sunlight Protocol
On a sunny morning, get outside for 5-10 minutes.
If it’s overcast, up the time to 15-20 minutes.
You can always do more if you like but focus on hitting the minimum thresholds first.
You can use that time to exercise, walk, or journal. It’s important to have your eyes open, so don’t meditate at this time if you close your eyes for that practice.
Face toward the sun but never look directly at any light source that causes discomfort or pain.
Protect your eyes.
What if it’s dark when I wake up or the weather is bad?
If you wake up before sunrise or the weather prevents you from going outside, turn on as many bright lights inside as possible.
Try to get outside as soon as the sun is out.
What about glasses, contacts, windows, and windshields?
Wearing eyeglasses and contacts (including those with UV protection) while viewing morning sunlight will not negate the benefits of the practice.
However, wearing sunglasses or blue light-blocking glasses or viewing light through a window or windshield will prevent you from getting the maximum benefits of morning sunlight.
Tool #2: Use Afternoon Sunlight to Reinforce Your Sleep
In the afternoon when the sun is low in the sky, try to spend some time outside (even if it’s overcast).
Viewing sunlight in the late afternoon or evening tells our circadian clock to start the process of winding down for sleep that night.
If you miss viewing morning sunlight, the afternoon sunlight also acts as a second “anchor point” to help maintain the consistency of your circadian clock and inform your brain and body of the time of day.
Tool #3: Leverage Light to Boost Daytime Energy & Improve Focus
To maximize your alertness and focus, turn on bright overhead lights in the morning until midafternoon.
Increase the ambient lighting, the overall illumination of a room, of your workspace rather than turning up the brightness of your computer screen and try to place your desk near a window for added natural light.
These lights will facilitate the release of dopamine, epinephrine (a.k.a. adrenaline), and norepinephrine which are associated with motivation, attention, and drive, and secrete optimal amounts of cortisol.
Stay in tune with the natural rhythm of the sun by dimming your work environment in the late afternoon.
Reducing blue light exposure, turning off overhead lights in place of lamps or softer lighting, and dimming the computer screen as the day winds down will all help for a smoother transition to sleep that night.
Tool #4: Avoid Bright Lights at Night to Protect Mood & Neurotransmitters
As we covered in Tool #1, viewing morning sunlight (specifically UVB rays and blue light) delivers a host of benefits such as improving mood, increasing energy, regulating appetite, and increasing dopamine release.
But UVB light exposure from artificial sources and screens at night (between 10 p.m. and 4 a.m.) negatively impacts depression and anxiety and decreases dopamine levels.
The bottom line?
Your health will suffer if you make a regular habit of looking at your phone or turning on bright lights, especially overhead lights, between 10 p.m. and 4 a.m.
Tool #5: Use Inexpensive Red Lights to Keep Nighttime Cortisol Low & Melatonin High
Maintaining low levels of cortisol, the “stress hormone,” at night is critical for sleep and immune system health.
The “sleep hormone” melatonin naturally rises in the evening to generate sleepiness and stays elevated through the beginning of the night.
But bright light powerfully suppresses melatonin.
So, if you need to get up in the middle of the night for some reason (i.e., to use the bathroom) try using no light or very dim light.
A better alternative to dim light is using amber or red light which has a smaller impact on melatonin levels. Any inexpensive red bulbs work fine.
Dr. Huberman experienced greatly improved sleep when he shifted to using red lights from 9 p.m. until he turns them off at bedtime.
This leads to our next point.
To achieve high-quality, deep sleep it’s critical for your room to be very dark while you sleep.
A study showed that even dim light exposure in your bedroom at night can increase insulin resistance and impair cardiometabolic function.
Insulin resistance: A state in which your cells stop responding to insulin properly. To compensate, your pancreas produces even more insulin in order to lower your blood sugar.
Cardiometabolic function: The health of your cardiovascular system (heart, blood vessels, and blood) as well as your metabolic system (the process by which our cells change the food we eat into energy). Cardiometabolic diseases are common but often preventable conditions such as heart attack, stroke, diabetes, insulin resistance, and non-alcoholic fatty liver disease.
Tool #6: Bright Red Light
Red-light therapy, a treatment that uses low-wavelength red light, is becoming more popular.
A study demonstrated that it can improve eyesight in those over 40 if done early in the day and help with acne and wound healing.
But for all of those benefits, a special red light is required.
These lights are available for purchase but cost hundreds or thousands of dollars. Red-light therapy centres are starting to pop up in large cities which offer a lower-investment alternative.
If you want to learn more, listen to the Huberman Lab episode on Using Light (Sunlight, Blue Light & Red Light) to Optimize Health.
Tool #7: Light Tips for Shift Workers
If you do shift work, here are a few light-based tips to help keep your sleep on track.
Use blackout window shades and dim lighting before bed to create good quality sleep. (This applies to everyone.)
If possible, try to stay on the same schedule for at least 2 weeks at a time. This will help your circadian clock better predict your sleep cycle.
Determine your sleep cycle and avoid looking at bright light in the middle of it. For comparison, this would be between 10 p.m. and 4 a.m. for the average person.
If you have young children or work night shifts, you might benefit from science-supported tools in the Huberman Lab episode called Find Your Temperature Minimum to Defeat Jetlag, Shift Work & Sleeplessness.
Tool #8: Get Sunlight On Your Skin for Optimal Hormone Health & Better Sex
The first 7 tips revolved around the benefits of viewing or not viewing (sun)light at certain times of the day for optimal sleep, performance, and physical and mental health.
But there is also an advantage to getting sunlight on your skin.
A study found that skin exposure to afternoon sunlight for 30 minutes increased testosterone, estrogen, mood, and libido in both men and women.
This practice can be as simple as getting outside for 20-30 minutes in the afternoon 2 to 3 times per week while wearing shorts and a short-sleeved shirt.
Just don’t sunburn.
That’s all folks!
I hope you enjoyed this week’s newsletter on light-based tools to improve health, well-being, and performance.
If you have any questions or just want to chat, hit reply to this email.
All responses go directly to me and I always reply!
Much love,
Jack