Spring is a beautiful time to reconnect with one of the most overlooked foundations of health: light. Getting outside into the early morning sun, without sunglasses, can have a powerful effect on overall health, especially when it comes to energy, sleep, circadian rhythm, and even thyroid function.
Light shapes life.
Just as real, whole foods from nature nourish the body in ways processed foods cannot, natural sunlight gives the body the kind of light it was designed to receive. By contrast, most of us are surrounded by what I think of as “junk light” after sunset: LED and fluorescent bulbs, streetlights, and the bright screens of our phones, laptops, TVs, and other devices.
This matters because the unnatural level of blue light in our modern environment disrupts circadian rhythm, the body’s built-in day-night clock. When that rhythm is off, the effects reach much farther than sleep alone. It influences blood sugar balance, appetite, hormone function, stress resilience, and thyroid health.
Why this matters for the thyroid
When it comes to thyroid health, light plays a much bigger role than most people realize.
Sunlight supports healthy T3 thyroid hormone activity and healthy vitamin A cycles, both of which are important for energy production and metabolism. Too much artificial blue light, especially at night, can interfere with both.
Light also affects other hormones that influence thyroid function.
For example, leptin is a hormone involved in energy regulation and metabolism. Healthy sunlight exposure, especially UV-A and infrared light, helps support normal leptin signaling. Too much blue light exposure, on the other hand, may contribute to leptin resistance, which can promote inflammation. Inflammation can then impair the liver’s ability to convert inactive T4 thyroid hormone into active T3 thyroid hormone.
Artificial light at night can also act as a stressor to the body.
When the body is under stress, cortisol patterns can become disrupted. In some cases cortisol may run high, and in others it may become depleted over time, while in others, the cortisol pattern spikes and drops at inappropriate times of the day. Cortisol that’s out of rhythm affects the signaling that supports healthy thyroid hormone balance. This is one reason many people continue to struggle with thyroid-related symptoms even when they’ve been told their labs are “normal.”
It is also one reason I do not believe thyroid health can be understood through TSH alone.
The good news: the action is simple
The science can sound complicated, but the first steps are surprisingly simple.
Here are a few places to begin:
- Get outside into the early morning sunlight, even for a few minutes. This can be as simple as sitting on your patio with your morning glass of water.
- Get as much natural daylight during the day as you reasonably can.
- Skip the sunglasses when possible, especially in the gentle morning light.
- Expose more skin to natural sunlight when appropriate and safe for your skin tone and environment. Skip the sunscreen but limit your direct sun exposure. Take time to gradually build a protective tan without burning.
- Reduce blue light exposure after dusk by dimming lights and limiting your screen time at night – less is best!
These simple shifts can have a real effect over time.
When I became more intentional about my own light habits, it changed much more than I expected. As someone who had been a lifelong night owl, I began waking up before my alarm. My afternoon energy crash disappeared. My overall energy improved. And I’ve seen similar shifts in clients who consistently apply these foundations.
A different way to think about health
If you have been struggling with sleep, energy, weight, or thyroid-related symptoms, it may be worth looking beyond food, supplements, and lab numbers alone.
Sometimes one of the most powerful missing pieces is also one of the most basic: the light you live in each day.
If you’d like help looking at the bigger picture of what may be affecting your health, my Thyroid Health Action Plan is a simple place to begin. Click below to learn more!
Frequently Asked Questions
What is light hygiene?
Light hygiene refers to the daily habits that help your body receive healthy light signals at the right times of day. This usually includes getting natural light in the morning, spending time in daylight during the day, and reducing artificial blue-rich light exposure at night.
Why is morning sunlight important?
Morning sunlight helps support circadian rhythm, which affects sleep, energy, hormone balance, metabolism, and overall resilience. It gives the body an important daytime signal that orchestrates the right timing for the production of hormones and neurotransmitters.
Can light affect thyroid health?
Light can influence many systems connected to thyroid health, including circadian rhythm, sleep, stress response, metabolism, hormone and inflammatory signaling. While thyroid concerns are complex, disrupted light habits may be one overlooked factor that contributes to how someone feels.
Can poor light habits affect sleep and energy?
Yes. Too little natural light during the day and too much artificial light at night can disrupt circadian rhythm. That often shows up as poor sleep, low morning energy, afternoon crashes, and feeling more awake at night than during the day.
Is artificial light at night harmful?
Artificial light at night, especially bright blue-rich light from screens and indoor lighting, may interfere with the body’s natural nighttime signals. For many people, reducing that exposure can be a helpful step in improving sleep and overall rhythm.
Should I stop wearing sunglasses?
If your eyes are sensitive to sunshine, ease your way into sun exposure. Start by wearing lighter color lenses and being mindful about not using sunglasses automatically all the time, especially in gentler morning or later afternoon light when natural light exposure is most supportive. Reducing exposure to artificial light at night will help tremendously, too. The more you get into sunlight near dawn or dusk without glasses on, the better your eyes will start to acclimate to the natural environment.
How can I improve my light hygiene?
A few simple places to start are getting outside soon after waking, spending more time in natural daylight, dimming lights after sunset, and reducing screen exposure at night.
Can better light habits improve thyroid symptoms?
Better light habits support the underlying systems that influence symptoms such as fatigue, poor sleep, and low resilience. While this isn’t a replacement for individualized care, it’s an important foundational piece.
What if my thyroid labs are normal but I still feel bad?
That’s more common than many people realize. Symptoms can be influenced by multiple factors beyond one lab marker, including sleep, circadian rhythm, stress load, blood sugar balance, inflammation, and daily habits.
What is a simple first step if I feel overwhelmed?
Start with one small change: get outside in the morning light for a few minutes each day. Simple, consistent actions are often more powerful than trying to overhaul everything at once.