Sunlight exposure has a number of benefits for both physical and mental health, including Vitamin D production, improved mood, better sleep-wake cycles, and improved skin health if you’re experiencing conditions such as acne, eczema, or psoriasis. We’ve been taught to fear the sun and slather ourselves in sunblock for the past two generations and we’ve lost sight of what sensible sun exposure means.
For these reasons and more, I encourage regular sun exposure, including sunbathing for my clients. In this article I’m covering why sun exposure is health giving, the problem with topical sunscreens, and how to get sensible sun exposure.
- How sunlight enhances your microbiome
- Cholesterol sulfate creation – an overlooked benefit of sunlight exposure
- Why suntanning is the best way to optimize your Vitamin D levels
- Why all sunblock creates harm and how to minimize its use
- How to safely suntan, with every skin type
Sunlight Enhances Your Microbiome
Gut health is foundation to our overall health and sunlight exposure can have a positive impact on the microbiome in several ways:
Vitamin D production: Essential for the growth and maintenance of beneficial bacteria in the gut, which make up your microbiome. Without enough vitamin D, the gut microbiome can become imbalanced, leading to a range of health problems. Unlike supplementation, your body will never create too much Vitamin D from sun exposure.
Melatonin regulation: Exposure to sunlight helps regulate your body’s natural circadian rhythm, which in turn regulates the production of melatonin. Melatonin is a hormone that plays an important role in regulating the immune system and promoting healthy sleep patterns. A well-regulated circadian rhythm can help maintain a healthy balance of gut bacteria. To reset your circadian rhythm, go outside for at least a few minutes of natural light first thing in the morning, around midday, and at sunset without sunglasses, regular glasses or contacts with UV protection, or sunscreen. You don’t need to spend a lot of time in direct sun exposure for this, just be outside. More is better when it comes to time outdoors.
Increased outdoor activity: Sunlight exposure usually means that you’re doing more things outside, which exposes you to a wider range of environmental bacteria, increasing your overall bacterial diversity.
Anti-inflammatory effects: Sunlight exposure has been shown to have anti-inflammatory effects on the body. Chronic inflammation can disrupt the gut microbiome, leading to an imbalance of bacteria. By reducing inflammation, sunlight exposure can help maintain a healthy balance of bacteria in the gut, as well as being beneficial for conditions such as arthritis and other inflammatory disorders.
Cholesterol sulfate creation – an overlooked benefit of sunlight exposure
Like Vitamin D, cholesterol sulfate is a molecule that is produced in the skin when ultraviolet B (UVB) radiation from the sun interacts with cholesterol in your skin. It’s used by other tissues throughout the body and has a number of important functions, including:
Maintaining the integrity of your skin barrier: Cholesterol sulfate helps to regulate the production and turnover of skin cells and can protect against damage from environmental stressors.
Supporting cardiovascular health: Cholesterol sulfate has been shown to help regulate the metabolism of fats and lipids in the body, which can help to prevent the development of cardiovascular disease.
Supporting brain health: Cholesterol sulfate is important for the proper function of the brain and nervous system. It has been shown to improve cognitive function and may play a role in the prevention of neurodegenerative diseases such as Alzheimer’s.
Overall, cholesterol sulfate plays a critical role in many different aspects of health and is an important molecule for maintaining optimal function of the body, along with the better-known Vitamin D.
Suntanning is the best way to optimize your Vitamin D levels
Vitamin D produced in the skin from sensible sun exposure circulates in the body two to three times longer than Vitamin D that’s ingested orally. In addition, all of the Vitamin D produced in your skin is bound to Vitamin D binding protein, which is what’s needed to ensure it is actively bioavailable. Only about sixty percent of what we ingest orally ends up bound to the D binding protein.
As we age our skin becomes less efficient in making Vitamin D from the sun. If you’re over 30, you’ll need to spend more time in the sun than you did when you were younger, and that time increases even more when you’re over 60. Between work and household responsibilities, it’s easy to slip into a largely indoor lifestyle by the time you’re in your 30’s. This lack of sunlight can be playing a role in the degeneration that appears to come with advancing age. To stay in optimal health, make time to sunbathe every day you can.
One important thing to know about Vitamin D is that it takes approximately 8 hours for the precursors in your skin to fully convert into Vitamin D3. Delaying showering, especially with soap or scrubbing, will allow your body to absorb more of this Vitamin D.
Why all sunblock creates harm and how to minimize its use
In the 1970s topical sunblock creams, also known as sunscreens, were first introduced as a way to prevent sunburning, and that ushered in the marketing campaigns that taught us to believe they were healthy and made us safer.
Sunscreens are designed to absorb UVB radiation from the sun. The common recommendation to use sunscreens with an SPF of 30 translates into the sunscreen absorbing approximately 95–98% of the sun’s UVB rays. That also means that the sunscreen reduces the capacity of your skin to produce Vitamin D by the same amount. Studies have shown that even using a low SPF sunscreen, with SPF 8, dramatically reduces blood levels of Vitamin D after tanning bed exposure.
While sunscreen is designed to protect our skin from the harmful effects of the sun’s ultraviolet (UV) radiation, which can cause sunburn, premature aging, and an increased risk of skin cancer in some people, almost all sunscreen contains chemicals that are harmful to human health and the environment.
One common type of chemical used in commercial sunblock is oxybenzone, which has been found to cause hormone disruption and has been linked to developmental and reproductive toxicity in animals. In addition, oxybenzone, zinc oxide, and other chemicals and minerals used in sunblock can accumulate in aquatic environments, causing damage to marine ecosystems.
To minimize the potential risks associated with sunblock, it’s important to choose a product that uses safer, more environmentally friendly ingredients. However, another concern with any type of sunblock is that it gives you a false sense of security, leading you to spend more time in direct sun than is sensible. This can increase your risk of sunburn and skin damage, even if the sunblock itself is a low toxicity type.
It may not be feasible to be completely sunscreen-free, but you can opt to use topical sunscreen only as a backup to other sun protection measures, such as putting on a hat, moving into a shaded area, wearing protective clothing, or carrying a large parasol.
How to safely suntan, with every skin type
It doesn’t take tons of sunbathing to produce all the Vitamin D you need. On average, between five and thirty minutes of direct sun exposure to your face, arms, legs, and back two to three times a week is sufficient in the summer. The sun is strongest between the hours of 10am and 3pm, so less time can produce a larger effect during those hours.
Age, skin color, air pollution, and the latitude you live at all impact Vitamin D production, so there’s no one-size-fits-all amount of time to spend in the sun.
Sensible sun exposure guidelines:
1. Use the “rule of nines” to estimate how much skin you have exposed to the sun, and how much Vitamin D is being produced. Your face and arms each equal about 9% of your skin; each leg, your belly, and your back each equal about 18% of your skin. That means if your whole body is exposed while you’re in a bikini style swimsuit, your body is creating about 7,000–10,000 IUs of vitamin D by the time you turn slightly pink, and the pinkness has disappeared 24 hours later.
Of course, your skin pigmentation matters, as does the strength of the sun’s rays at different times of day, so think of this as a general rule of thumb, while understanding that light skin is going to absorb more UVB rays over the same duration than darker skin. You won’t need to run scientific calculations if you listen to your own body’s signals for what sensible sun exposure feels like on your skin. When you’re in the sun ‘bare’ you’ll feel a sensation that you’re getting too much sun, to me it feels like my skin is crinkling or shrinking back. I honor that feeling by covering up or moving to a shaded area.
Since the skin of the face is more prone to sun damage and skin cancer, I personally choose to keep my face out of the sun, and I’m happy to be getting about 90% of my skin exposed when I sunbathe.
2. Gradually increase sun exposure: Start with short durations of sun exposure, earlier in the day, especially if you have fair or sensitive skin. Increase the time spent in the sun gradually to allow your skin to adapt and minimize the risk of sunburn.
3. Seek shade during peak hours: The sun’s rays are strongest between 10am and 3pm During these hours, it’s advisable to seek shade or use protective clothing like hats, long-sleeved shirts, and parasols to minimize direct exposure when it feels too intense for your skin type. However, if you live at a latitude far from the equator, this might actually be the best, or only, time your skin will produce Vitamin D. Always listen to your body over generalized advice.
Slight pinkness of the skin up to 24 hours after sun exposure is perfectly safe, but avoid bright pink/red sunburn that lasts longer and leads to peeling of the skin.
Since glass absorbs all UVB radiation, sun that you’re getting through glass, plexiglass, and plastic will not count towards sunbathing and won’t produce any Vitamin D.
Sunbathing is a requirement on the GAPS Protocol because sunlight is a necessary nutrient to the human body and we’ve become deficient, which leads to a depressed state of health. Sensible sun exposure is the solution to lack of sunshine that we’ve collectively experienced for the past couple of generations. Your body was made to be outdoors most of the time and as you learn to listen to your own skin and trust your body’s signals, you’ll settle into the amount that’s sensible for you.