The Benefits of Sunlight for Sleep and Hormones

In our chaos-packed world, we want to wake up and hit the ground running, especially as busy moms. Despite having the best intentions and long to-do lists, we might not always hit the mark. We may find ourselves sleeping in because we are low on energy or plagued with headaches from hormone imbalances.

There are many things that can trigger poor sleep, hormone problems, or stress. But one of the most natural (and cheapest!) ways to find some relief from those things is often overlooked—sunlight exposure. There are science-backed benefits to getting morning sunlight exposure. And it’s not just about helping you wake up!

Getting morning sunlight is more than just getting your vitamin D. The good news is that you can reap the health benefits of morning sunlight exposure all year long—even if you have to do it indoors.

Read on to learn all of the important ways that bright morning sunlight can support good health. It might even be the missing piece of your wellness puzzle.

3 Essential Benefits of Sunlight

People associate sunlight with the benefits of vitamin D, but even if your vitamin D levels are great, you still need morning sunlight.

Our ancient ancestors rose with the sun and slept when it set. Human bodies weren’t made to be on the go for 18 hours a day or more. Yet being the modern moms we are, we often burn the candle at both ends.

There are many physical and mental health benefits when we set our body clocks to be in sync with the sun.

When we talk about sunlight, we’re actually discussing UV rays. We are exposed to two types of sunlight—UVA and UVB. UVA comes through windows, but glass blocks UVB rays. UVB helps with vitamin D production, but UVA offers other sunlight benefits.

Improved Physical Health

Morning sunlight exposure supports a ton of different physiological processes in your body. Not only can outdoor sun exposure support vitamin D levels, but other biological processes happen in the body when exposed to sunlight.

These include:

• Nitric oxide: When exposed to sunlight, outdoors or indoors, the skin releases nitric oxide from storage into the bloodstream. This compound triggers your arteries to dilate. When your arteries are dilated, your blood pressure lowers. Constant stress can lead to higher blood pressure, even in people who don’t have blood pressure problems or cardiovascular disease. Lower blood pressure is good for the heart and it could also help to decrease headache frequency.

• Heme-oxygenase: When your skin cells are exposed to the sun, a compound known as heme-oxygenase is stimulated. It triggers when cells are stressed, which happens from UV exposure. However, not all cellular stress is a bad thing. In this case, moderate amounts of sun exposure can lead to increased production of iron and carbon monoxide. While carbon monoxide is deadly if breathed in, when converted in the cells in small amounts, it prevents the production of inflammatory cytokine cells. So sun exposure triggers a built-in anti-inflammatory cell effect.

• Immune cell regulation: The immune system has a complex arsenal of different cell types. When one type of cell does not function or is produced in imbalanced amounts, the immune system can become suppressed or stimulated. This can lead to autoimmune disease, inflammatory conditions, or even cancer. UV exposure can increase the activity of T-regulatory cells. These are the immune cells that tell other types to calm down. T-regulatory cells are often lacking in people who develop autoimmune disorders. By supporting the immune system’s ability to regulate itself, you can protect your overall health. This also protects from excessive inflammation and neurodegenerative disorders like multiple sclerosis.

• Metabolic function: Type 2 diabetes, heart disease, and even cancer are associated with problems in the way the body is able to break down and use glucose. This is tied to insulin response, other hormones, and many different factors. Metabolic syndrome is related to blood pressure, diabetes, obesity, and many other health issues. As many as 20-30% of people around the world are dealing with this disorder. However, sunlight and UV exposure can help with this because it promotes normal metabolic function. Studies are ongoing as to the specific type, amount, and broad spectrum of benefits. Regularly getting morning sunlight helps balance the circadian rhythm. This can support better appetite regulation, which can improve overall metabolic markers.

Mood and Mental Health

The benefits of morning sunlight extend well beyond specific markers of physical health. It can noticeably impact your mood, mental health, and stress perception. People with seasonal affective disorder develop symptoms because of the lack of bright light exposure.

Having low vitamin D levels is tied to a greater risk for depression. However, it’s more than just vitamin D.

In addition, decreased sun exposure is tied to cognitive impairment, unrelated to nutritional status. This happens for a few reasons. Natural sunlight has a direct effect on circadian rhythm. This affects how the hypothalamus works in the brain, directly impacting several factors like levels of serotonin and melatonin.

Serotonin is a neurotransmitter that promotes feelings of calm, balance, and well-being. Without enough light wave exposure during the day, serotonin cannot produce enough melatonin to induce a regular sleep cycle later. Being unable to sleep leads to chronic exhaustion and sleeping in later, which decreases potential morning sunlight exposure. It becomes a vicious cycle of neurotransmitter imbalance, low mood, and stress.

This hypothalamus brain network also influences things like:

• Body temperature regulation
• Energy levels
• Blood pressure
• Digestive function
• Hormonal systems
• Immune activation

Think about morning sunlight as the charging cord for your brain. You can’t expect your laptop to work if you don’t charge the battery. If your brain consistently does not get signals from light waves, especially in the morning, it will struggle to sense the time of day and the type of signals it should send to all of your body systems. The result can be a meltdown in one or more areas that can make you feel like your whole body is misfiring!

Light wavelengths also have a strong influence on how much blood is available to your brain. Studies show that blood flow in the brain improves after light therapy. Decreased blood flow in the brain is tied to cognitive problems, low mood, poor sleep, and even age-related problems that could be preventable.

Sleep Quality

We already know that serotonin triggers the production of melatonin. If your brain is off earlier in the day, it may not make enough melatonin. This could lead to insomnia or problems sleeping well through the night. While you can supplement with melatonin, that won’t permanently fix the situation. Your brain needs to be getting the right signals from light waves so it can keep the rest of your body on a healthy schedule.

Sleep disorders alone cause many health problems. They may be at the root of many issues, including:

• Immune system problems
• High blood pressure
• Diabetes
• Obesity
• Different types of depression

Having a circadian rhythm that is out of sync is not an easy problem to fix… unless you go to the source. The internal body clock is tied to the pattern of the sun. Regulating your body’s internal clock can easily be done by aligning yourself to the schedule the sun has already set. This is, of course, challenging for people who do shift work or for parents who have infants and small children. But still not impossible! We’ll talk more about how to make these changes below.

Benefits of Sunlight: Who Needs It?

Everyone needs sunlight exposure! Literally every human being. However, there’s not a one-size-fits-all formula for how much you specifically need. The factors that depend on your sunlight exposure for vitamin D range dramatically, depending on:

• Your skin type
• Your latitude
• The time of year
• Your other health factors
• Your diet

I talked to Ari Whitten about all the health benefits of sunlight in a podcast episode. Some of you may have poor sun tolerance, sunburn easily, or just generally be sensitive to it. I used to be that way. But dietary changes, especially when it comes to antioxidants and phytonutrients, can increase sun tolerance. It goes to show that dysregulation in any one area, like diet or lack of sunlight, can magnify those effects in other areas.

I get that it can be hard to find balance in every area of your life, especially when you have small kids or you’re parenting and working. But small steps toward balance can have a big impact, especially when we are consistent with them. Showing up for morning sunlight every day can invest in a healthy mood, good sleep, lower stress levels, better digestion, and so much more.

You need sunlight exposure if you’re a well-rested executive, a burnt-out mother, or a late-night dorm-living college student. Everyone needs morning sun exposure to facilitate all of the vital body processes that we never see… until they start to misfire. Vitamin D supplementation can support many aspects of health, but it won’t replace the sun’s rays.

Only your dermatologist can assess your personal health and give you medical advice. But for many, moderate sun exposure with or without sun protection is safe. Melanoma is typically the result of many factors, including total childhood sun exposure, other health factors, and more.

How to Get Morning Sunlight

When you are already busy or overwhelmed, it can be hard to add something new to your day. There are easy, practical ways to work morning sunlight exposure into your existing habits. The payoff is well worth the slight adjustment to your morning routine.

To get the benefits of sunlight, you don’t just need to expose your skin. You also need to expose your eyes! I’m not talking about staring into the sun. I talked to Matt Maruca on the podcast, and he explained that the way light comes in through an ocular pathway can have a significant impact on how the brain processes information, including light. Your skin takes in UV rays, but your eyes also facilitate sending signals to your brain. Wearing sunglasses can get in the way of these benefits.

If you are sensitive to bright light, you can spend some of your time with your eyes closed. But you will build up a tolerance as you get used to it. If you are typically indoors a lot, or your sun exposure is normally later in the day, the morning sun can feel blinding. But this type of light is what sets about the brain, hormone, and overall body balance that is needed to get your internal clock reset.

I like to begin my day with a cup of tea or coffee and sit outside on the front porch. If you are a morning person, try waking up slightly before the kids and bring a book or your favorite drink outside for just 10-15 minutes first thing in the morning.

Indoor Sunlight

Unfortunately, you can’t get vitamin D through a window. Glass blocks a specific type of UV ray that creates vitamin D in the body in response to a cholesterol conversion. Sunscreen also affects the way that UV light can produce vitamin D in the body. However, as we’ve already discussed, morning sunlight is important for your health, even without vitamin D.

If you want to work morning sunlight into your routine but you can’t easily go outdoors, consider the following:

• Find a window that faces the east. If you live in an apartment that has no east-facing windows, find a public space in your apartment that has sun exposure. If neither of these work, find a coffee shop or a place that is part of your morning routine that can give you direct eastward-facing sunlight.
• You don’t need to sit in the sun for hours. If you’re new to sunlight exposure, or if you are pressed for time, even 5-10 minutes of consistent morning sunlight every day can start to improve your internal body clock.
• If you have small kids, take them with you! You don’t need to do this solo. I noticed a major improvement in my health when I started sitting in the sun every morning with my family. Plus, they got the same health benefits that I did. If you can’t take them all outside, you can sit together in front of a bright morning light window or doorway.

Outdoor Sunlight

There are additional benefits to outdoor morning sunlight. Vitamin D production depends on a lot of factors and isn’t necessarily as important first thing in the morning. But with outdoor morning sunlight, you also get fresh air, which has plenty of benefits on its own!

Morning sunlight can make outdoor sun exposure easier in the summer for people who have heat intolerance. Even if it’s winter, bundle up and keep your eyes and face exposed to the light, you still get those benefits of taking in the bright morning rays through your eyes. Your brain will still get the message!

In what ways could morning sunlight improve your quality of life? Do you already do this? Share your experiences in the comments below!

Sources:

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