The Light Effect : Why Our Body Craves the Sun, and How I Use it to Heal

Did you know sunlight can reset your sleep, boost your energy, and even strengthen your immune system? In this episode, we dive into the science of light exposure, why your body depends on it, and simple ways to use natural light to feel your best every day.

Links: 

Why We Sleep by Matthew Walker

Huberman Lab - Podcast #84 (Starting at 26 minutes) 

Blue light blocking glasses

DMinder App

Transcript

Natalie: 0:41

Welcome back to Design Your Well Life. We are diving into a glowing topic today. One that most of us take for granted, but that has the power to completely transform our energy, sleep, mood, and even our immune system. We're talking about light. It's something that we encounter every single day, but are we using it the way that nature intended? Or have we, in our modern lives, lost touch with one of the most powerful tools for healing, vitality, and well being? If you've ever felt more awake after stepping outside in the morning, or strangely calm watching a sunset, you've already experienced the profound biological effects of light, even if you didn't realize it. And with Daylight Saving time kicking in this week, it's the perfect time to talk about how light influences our circadian rhythm, and why bad lighting is destroying our sleep. How morning sunlight literally charges our body like a battery. How sunlight helps turn cholesterol into vitamin D. Yes, really. Why people feel energized in the sun. There's a real reason for this, and we're going to break it down. The surprising link between light exposure and vision health and whether or not we should all be wearing blue light blocking glasses in the evening. So, let's start today by talking a little bit about the forgotten healing power of light. Now, I'm not sure of your particular beliefs, and it's okay if we don't believe the same. However, I personally am a Christian, and believe that God gave us both the sun, S U N, and his son, S O N, for physical and spiritual healing. There are many metaphors between the two. The light of Christ is the divine energy, power, or influence that proceeds from God through Christ and gives life and light to all things. Likewise, the sun, S U N, provides the earth and all living creatures the energy and sustaining power that it needs to give light and life to all things. For centuries, people understood that the sun was more than just a bright ball in the sky. In ancient Egypt, they worshipped the sun god Ra. Sunlight was considered a divine healer. The Greeks used heliotherapy, sunbathing as a treatment for illness. And in Ayurveda, morning sunlight was believed to balance energy and even boost digestion. But today, we spend 90 percent of our time indoors under artificial lighting that's doing the exact opposite of what our bodies need. We wear sunglasses, we slather ourselves with SPF 100, which, don't get me wrong, has its place, and avoid sunlight like it's some kind of enemy. But the truth is, we need light. Our bodies thrive on it. So in today's episode, we're peeling back the layers to rediscover what ancient civilizations always knew, light is key. And by the end of this episode, you'll not only understand why it's so powerful, you'll have simple practical ways to start using it to feel better, to sleep deeper, and actually supercharge your energy every single day. Sound good? Let's dive in. So we're gonna start by trying to understand what light's influence is on our biological clock. Have you ever wondered why some people naturally wake up feeling refreshed while others hit snooze five times before dragging themselves out of bed? It's not just personal preferences or bad habits. It's actually biology. Our bodies are governed by an internal 24 hour clock known as circadian rhythm, which controls everything from our sleep wake cycles to hormone release and metabolism. Now, one of the most powerful regulators of this rhythm is light. As a side note, we touched on this a little bit in our sleep episode. And if you'd like more information, I would highly recommend Matthew Walker's book called Why We Sleep. Now, when light enters our eyes, it does more than just help us see. It directly influences a part of the brain called the Suprachiasmatic Nucleus, or SCN for short. This little area in the hypothalamus acts like the master control center for our biological clock. You can think of it like the conductor of an orchestra. It keeps everything in sync. It takes the signals from the light around us and it tells our body what time of day it is. If you've ever felt jet lagged after traveling across time zones, That's your circadian rhythm getting thrown off because the light cues that your body expects don't match the environment that you're in anymore. Dr. Andrew Huberman is a neuroscientist at Stanford university, and he has extensively studied the relationship between light and the brain. He emphasizes that morning light exposure is one of the most powerful tools for setting your circadian rhythm. The reason? It triggers a cortisol spike. which, despite its bad reputation, it's actually beneficial in the morning. This naturally wakes us up, improves focus, and sets us up for better sleep later that night. But here's where things start to break down. Our modern life has completely disrupted our relationship with natural light. Our ancestors rose with the sun and spent most of their days outdoors. Now today, most of us wake up to phone screens. We sit in artificial lit offices and rarely step outside. In fact, the average American spends 90 percent of their life indoors. And this was reported by the National Human Activity Pattern Survey back in 2021. That's like asking your body to function without the very thing it was designed to respond to, natural light. Now, this reminds me of one of my most favorite nostalgic movies, does anyone remember Joe vs. the Volcano? He starts off the show working in an office with no windows, and he feels like he is constantly sick, he even believes he's dying. But as the show progresses, and he gets outside into the sunlight, his life takes an amazing turn. I might have to watch that this week. And what about sunglasses? If the only time you go outside you're wearing dark lenses that block the natural light, your body never gets the full benefit of sun exposure and syncing with the time of day that it actually is. Sunglasses are great for midday protection if the sun is at its highest peak, if you're getting a lot of glare. But in the first few hours after waking, you really want to get the full spectrum of light directly on your eyes, so no shades. Dealing with our bodies and light right now, it wasn't always like this. As I mentioned earlier, ancient civilizations deeply understood the power of light. For thousands of years, humans lived in harmony with natural light. It's only in the past century that we've moved away from it. And it's no surprise that our sleep, energy levels, and overall health have also suffered. But the good news? We can take simple steps to get back in sync with nature's natural light cycles. Now, If you prioritize morning sunlight exposure and minimize artificial light at night, we can reset our biological clock, which will really improve your sleep quality. And you're going to feel more energized throughout the entire day. We can learn to live in this modern world by learning from the past and how to interact with light to optimize our own wellbeing. There's so many great inventions that have been made, but by also making these inventions, it's pulling us away from nature and putting us indoors in an environment that's not always the most healthy for us. So, let's move on and talk a little bit more specifically about morning light and why this is nature's energizer. Now, have you ever noticed after spending time in the sun, first thing in the morning, it makes you feel awake and clear headed. It's not just your head. There's actually real science behind it. Morning light literally charges your body like a battery. So here's how it works. When morning sunlight enters your eyes, it activates special receptors in the retina called melanopsin cells, but that's not all. Morning sunlight also stimulates the production of serotonin. Serotonin is a neurotransmitter that plays a huge role in mood regulation. More serotonin means feeling happier, more focused, and more emotionally balanced throughout the day. Now, it's no coincidence that people tend to feel happier and more energized during the summer months, when there's more light exposure. Seasonal affective disorder, or SAD, is a perfect example of how a lack of light can directly impact your mood. Many people experience these depression like symptoms in the winter, and doctors often prescribe light therapy boxes to mimic natural sunlight and help regulate the serotonin levels. This was an NIH study in 2022. But the truth is, we don't need these fancy devices. We just need to step outside in the morning. Even in the winter, the morning light is enough to give a boost if we intentionally find time to get outside. One of my favorite activities is to take a walk in the morning. I feel like this is my daily therapy, especially if I bring along a friend and my dog. Now between the movement that activates my lymph system circulation, the fresh air and deep breathing to get oxygen flowing through my system, and the morning light that gives me a boost of energy and just resets my day, it is definitely what I look forward to. And if you're thinking, but I don't have time to sit in the sun every morning, you don't have to. You can stack this habit with something that you're already doing. You can have your breakfast outside. Go ahead and take a short walk, like I just mentioned, or simply stand on your porch or balcony for a few minutes before heading out for the day. Even cloudy mornings still provide enough natural light to set your circadian rhythm. Outdoor light is 100 times brighter than the artificial lights inside your home, even on cloudy days. Now, I get it. Not everyone wakes up to warm sunny mornings year round. Where I live, winter brings freezing temperatures, snow, and a lot of darkness, which can make it tricky to get that all important morning sunlight. But over the years, I've actually figured out some hacks to make it work. Because let's be real, staying inside all winter really is not an option. Since it's still dark when I wake up in the winter, I've had to get creative. Now, most days, I'm already on my way to work by the time the sun is just peeking over the mountains. So, here's what I do. I roll down my car windows. Yes, all the way down. I crank up the heater and I soak in as much direct sunlight as I can while I drive. And before you ask, no, getting sunlight through a windshield doesn't count. Tinted glass blocks the full spectrum of light that your body needs. So if you're in a car, let the light hit your eyes directly. The key takeaway? Get outside and get that low angle morning light as soon as you can, ideally within an hour of waking. Even if it's just for a few minutes, step outside, stand on a porch, or take a quick walk. And when you do, look towards the sun, but not directly at it. A couple more tips here. Skip the sunglasses first thing in the morning. Your eyes need the direct exposure to the light to trigger the right hormonal responses. However, if you wear corrective glasses or contacts, those are totally fine. As long as you don't have the blue light blocking film that goes over the top of your corrective glasses. Now, how long should you stay outside? According to Dr. Andrew Huberman, it takes five minutes on a clear day, 10 minutes if it's cloudy, and up to 30 minutes if it's raining or snowing to get that natural blue light that you need in the morning to reset your circadian rhythm. If you can't do that much, get what you can. Something is better than nothing. And what if you wake up before the sun is even out? Like I do. Or, right now, with daylight savings time, your mornings suddenly feel darker. Flip on your interior lights first thing when you wake up. No, artificial light isn't the same as natural sunlight, but it helps kickstart your body's wake up process until you can get outside. The most important thing, once the sun does start to rise, Get outside as soon as you can. There's about a 90 minute window while the sun is still at the level where it's producing those blue light effects to kickstart your day. Even if it's freezing outside, even if it's cloudy, your body is going to thank you for this. And if you want more details on all of the science behind morning light exposure, Dr. Huberman has a fantastic episode on this topic, which I'll link to in the show notes. Now there's also a growing trend in the biohacking community that takes morning light exposure to the next level. Dave Asprey, the founder of Upgrade Labs, swears by sun gazing and getting direct sunlight exposure on his skin first thing in the morning. He argues that this not only regulates his circadian rhythm, but also helps regulate metabolism and mitochondrial function. Now, while you don't need to go full on biohacker, the key takeaway is simple getting morning light, even just for a few minutes has enormous benefits for your energy and your mental clarity. So if you're feeling sluggish in the mornings or you find yourself reaching for caffeine just to function, try this experiment for me. Get at least 10 minutes of outdoor light exposure within one hour of waking up every day for a week. Track how you feel, track if you're sleeping better, if you feel more energized, and if so, congratulations! You've just started retraining your brain to wake up the way that nature intended. So what are other outdoor benefits that we get? Let's talk a little bit about vision and your eyes. Another fascinating benefit of light and spending time outdoors is that it is great for your eyes. This is especially important for children while their vision is still developing. But honestly, it's something all of us should be paying attention to. Studies show that spending just two hours outside each day can significantly reduce the risk of developing nearsightedness. And it all comes down to how our eyes are designed to function. See, when you're looking at something far away, like the horizon, your eyes lens naturally flattens out and relaxes. But when you're focusing on something up close, like a book or a screen, your eye muscles have to work harder to thicken the lens and bring light into focus on the retina. Over time, if we only focus on things up close for long periods, our eyes can adapt in a way that leads to nearsightedness. So if you spend a lot of time reading or working on the computer or staring at a phone, give your eyes a break. Every 90 minutes or so, look up. Look from whatever you're doing and focus on something in the distance. If you have access to a window, gaze outside towards the horizon. If you're in a space without windows, at least look across the room, and this is a great time to let your face and your jaw and your eyes all relax because these muscles are all interconnected. Now, this topic is actually deeply personal for me because of one of the autoimmune diseases I have that cause significant eye deterioration. And for a while, it felt like my vision was just getting worse every few months, but I started making intentional changes. By focusing on clean, nutrient dense food, getting plenty of sleep, and prioritizing my time outdoors throughout the day, at my last eye appointment, something incredible happened. That deterioration I had been experiencing had reversed. This was a huge reminder that small, consistent habits really do matter. Our bodies are designed to heal, repair, and function optimally when we give them what they need. And something as simple as spending more time outside can make a real difference, not just how we feel, but in how we see the world. Now let's talk a little bit more about the sunlight, vitamin D, and how that fuels our immune system. We've talked about how morning sunlight boosts serotonin and improves the mood, but sunlight does more than just make you feel good. It literally strengthens your immune system. At the center of this is vitamin D, which is called the sunshine vitamin. Now, when UVB rays from the sun hit your skin, they kickstart a process that converts cholesterol into vitamin D3. This gets further processed in the liver and kidneys until it becomes the active form of vitamin D that your body can actually use. Vitamin D is most famous for helping your body absorb calcium for bone health, which most of us know, but recent research has uncovered an even more important role, immune function. It activates key immune cells, helping them fight off infections, reduce inflammation, and even lower the risk of autoimmune disease. And this was from a study by the National Institute of Health back in 2022. This is also why people tend to get sick more often in the winter. The lack of sunlight means less vitamin D production, which can leave the immune system more vulnerable to colds, flu, and other infections. So, how much sunlight do you actually need? The answer depends on factors like your skin type, your geographical location, and what time of year it is. In the summer, you might only need 10 to 15 minutes of midday sun in order to generate enough vitamin D. But in the winter, UVB rays are too weak in many locations to even produce any vitamin D at all. This is why I love using the D Minder app. It tracks your location and it tells you when UVB rays are strong enough to produce vitamin D, as well as how long you should stay outside before burning. It's an easy way to make sure that you're getting what your body needs without overexposing yourself. Now here's something really interesting about how sun works with vitamin D production. When the sun is at a 30 degree angle or lower in the sky, it doesn't produce UVB rays, and without UVB rays, your body can't make vitamin D. In the summer, this usually only happens at sunrise and sunset, so you still have plenty of midday hours to soak up that vitamin D. However, in the winter, it's a different story. Where I live from mid October to mid February, the sun actually sits at such a low angle all day long that there's literally no UVB exposure for months. No UVB means no vitamin D production. Now here's why this all matters. Our bodies use about 600 to 800 IU of vitamin D per day just to function. So if we don't have enough stored from the summer months, our levels can drop too low, and it leaves us more susceptible to sickness, fatigue, and mood changes. So what can we do? There are a few options. Some people supplement with vitamin D, while others invest in UVB lamps. Now, the lamps, by the way, can be pretty expensive, and I'll go deeper into how different type of vitamin D supplements and the lamps work in a future episode. But for now, the takeaway is simple. If you live somewhere with long winters, you probably need a plan to keep your levels up. For me, vitamin D tracking has become a daily habit. About a year ago, I had a full DNA panel done and learned that my body doesn't absorb vitamin D very well. And in addition to that, it struggles to convert it into a usable form. So basically, that means I need to take about three times the amount most people need just to hit a healthy level. Now I've tried multiple supplements and drops, but personally, I've had the most success with getting outside whenever UVB light is available. And let me tell you, I physically feel the difference on days when I spend more time in the sun. So Moving from vitamin D and sunlight, let's start talking about the spectrum of light and the difference between morning, midday, and evening light, and why all of them matter. So, we all know, light isn't just on or off. There's a spectrum there. The way sunlight changes throughout the day actually sends different signals to your body. Now, each phase of sunlight really plays a different role in regulating hormones, energy levels, and overall health. We'll start with morning light. So, morning light, for example, is really rich in blue wavelengths. This is the light that tells your brain, hey, it's time to wake up. It signals your brain to stop producing melatonin and start releasing cortisol, which is exactly what we need to feel awake and ready to take on the day. This is why blocking blue light in the morning with sunglasses or blue light glasses is really counterproductive. Midday light is the strongest and it contains those UVB rays that we just talked about, which are crucial for that vitamin D synthesis. This is why midday sun can really feel energizing. And evening light starts shifting towards the warmer tones. Reds, oranges, ambers, this is nature's way of telling our body it's time to wind down. These warm hues actually trigger the melatonin production that our body needs and it helps us fall asleep more naturally. But here's where modern life is throwing a wrench into this perfectly designed system. Instead of following this natural light cycle, most of us go from looking at bright daylight to looking at bright artificial light in our homes, especially our computers and our phones. Now, instead of gradually dimming the light in the evening, which would naturally trigger melatonin production, we get the exact opposite, this constant artificial blue light stimulation. And if you remember, it's the blue light that keeps us awake. That's why experts like Dr. Huberman and other neuroscientists recommend limiting bright artificial light exposure, specifically blue light after sunset. Instead, opt for that warm, dim lighting in the evening to mimic the natural fading sun and prepare your body for sleep. Now, we discussed briefly in our sleep episode the importance of turning off your overhead lights and using a low dimmable lamp in the evening. I also take the blue light blocking glasses to an even deeper amber level. Dave Asprey makes amber glasses and you can also find several varieties on Amazon. I had a friend introduce these to me and I just ordered a pair to use about an hour before sunset and then throughout the rest of the evening when I'm on my phone or my computer. But ultimately, I aim to shut down all my electronic devices that produce any sort of blue light at least one to two hours before I go to bed. Now, I'm going to do a future episode about a product that I've begun using in custom homes. It's a lighting company that's called Ketra, and it's part of the Lutron system. They've made a smart lighting system that uses the exact geo placement of your house and can identically match the changing light color from the natural light outside to the light color inside your house. Now, what does this mean? In the mornings, when the natural light is producing more blue light, Your inside lights will match that same blue light intensity. Midday will be more warm and bright, and in the evening as it approaches, your lights will naturally dim and produce that red light your body needs to signal the melatonin production for your approaching sleep. I'm actually so impressed with this system, and I've been trying out the bulbs in my own bedroom for the last six months, and have loved the effect that it's had on promoting my natural circadian rhythm. So more to come in future episodes on this specifically. Now, let's move on to navigating this artificial and blue light and sleep. How do we sync all of this together? We know that artificial light is a problem. We've established that natural light is one of the most powerful tools for setting our internal clock. But the modern world is full of all this unnatural light, especially blue light, and we're really not going to get away from this completely. Here's the science behind it. Blue light, whether it's from LED bulbs, fluorescent lights, or your phone screen, tells your brain that it's still daytime. It stops the melatonin production, which we learned is crucial for falling asleep and staying asleep. A 2015 study from Harvard found that exposure to blue light before bed can delay melatonin release by 90 minutes. Now, that means you could be lying in bed exhausted, but your brain is still getting the signal to be in day mode. This is going to make it much harder to drift off to sleep. So the bottom line, we can't completely eliminate artificial light from our lives, but we can make small changes to align with nature's rhythms. All right, my friends, we've just taken a deep dive into the world of light, how it shapes our circadian rhythm, how it fuels our immune system, and even impacts our mood, our sleep, our energy levels. We've talked about why morning sunlight is the ultimate natural alarm clock, why midday sun is a powerhouse for vitamin D and why sunset light is nature's way of telling us to wind down. We've also explored how modern artificial light, especially blue light is messing with our biology and what we can do to fix it. But here's the thing. None of this information will change your life unless you actually put it into practice. And I get it. We're all busy. Some of us are up before the sun even rises. Some of us work indoors all day, and some of us, let's be honest, are just not morning people. But I want to challenge you just for a week to experiment with light exposure in a way that works for your life. Okay, so here's our listener challenge. Let's do a light reset week. And this could completely change the way that you feel each day. For the next seven days, I want you to intentionally engage with light at the right times and see what happens. So here's what to do. Step one, get outside within the first hour of waking. Even if it's cloudy, even if it's cold, give your body the light it needs to reset your internal clock. Now here's a little bit more information on that. If you're doing this challenge with me the week of March 9th, we've just shifted into Daylight Savings Time. In Utah, First light happens at 7:22 AM and sunrise is at 7:47 AM, meaning you have the best morning blue light window until around nine o'clock AM. But wherever you are, check the D minder app or a sunrise tracker and find your ideal timing for that morning light. Now, step two, get 10 to 15 minutes of natural midday sun. This is your vitamin D boost. If you're stuck inside, open a window, step onto a balcony, or take a quick walk. For those of us in Utah this week, the UVB exposure is going to be strongest between 11 a. m. and 4. 30 p. m. With solar noon peaking about 1: 38. So try and get outside at some point during this window. Step 3. Limit artificial blue light after sunset. Use warm lights, dim your overhead lights, and if you must be on a screen, switch it to night mode or wear blue light blocking glasses. For the week of March 9th, sunset is at 7:26 p. m. So if you can step outside and actually watch the sunset, that would be fantastic. This helps tell your brain, hey, the day is winding down. And try switching to blue light blocking glasses around 6 p. m. And aim to turn off all your screens about 2 hours before you go to bed. Now, final step, step 4, with these three time periods of being outside, track how you feel. Are you waking up easier? Did Daylight Savings time change not affect you quite as much? Are you sleeping better? Do you feel more energized during the day? I want you to really pay attention to what changes you experience and share them with me. DM me on Instagram or click the comment button on my podcast. Let's see how this light reset week actually works for you. So, final thoughts, and here's from a design perspective. Our lives should be designed with light in mind. Just like we carefully choose colors, textures, and furniture in our homes, we need to be just as intentional on how we interact with light. Because the truth is, our bodies are designed to thrive in these natural rhythms, and when we honor that, and we actually live in sync with the sun, We really do feel better. We sleep better. We function better. Thank you so much for joining me today. Let's create a ripple effect of people taking back their health one sunrise at a time. Now, until next time, stay bright, stay well, and keep designing your well life.

33:44

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