The Healing Power of Sunlight: Your Guide to Healthy Sun Exposure

Sunshine is the forgotten medicine. In today's article, we will be covering the history of heliotherapy (sunshine therapy) and talking about controversial topics such as sunscreen. I will also cover the best times of day to step outside, since different rays from the sun offer different health benefits.

Ancient civilizations already knew about the powerful healing abilities of sunshine. Egyptian physicians observed that people living in sunny climates had stronger bones, and they routinely prescribed sunbathing for general vigor and healing. Hippocrates, the father of modern medicine, practiced heliotherapy at his healing temple on the island of Kos; he prescribed sunshine for treating obesity and healing wounds. Wealthy Romans built solaria on the roofs of their villas, and Roman physicians like Galen and Celsus routinely prescribed sunlight to treat arthritis, epilepsy, and skin conditions.

Following the fall of Rome, Europe entered a long period where public bathing and outdoor exposure fell out of favor. However, by the late 18th and early 19th centuries, the industrial revolution forced a change.

As populations crammed into smog-choked, sunless factory towns, two major health crises erupted: Tuberculosis (TB) and Rickets (a bone-softening disease in children). Doctors noticed a stark contrast—children in rural, sunny areas rarely developed rickets, while up to 80% of children in industrialized, dark cities like London suffered from it

Auguste Rollier (centre) seeing a patient undergoing heliotherapy in his clinic in Leysin (Copyright: Association pour le Patrimoine de Leysin)

The Golden Age of Heliotherapy (Late 1800s – Early 1900s)

Probably the most famous heliotherapist in history was Swiss physician Dr. Auguste Rollier, who opened a network of sun clinics high in the Alps. He treated patients suffering from systemic, deep-tissue, and bone tuberculosis (which was considered a death sentence at the time). Without using a single drug, Rollier cured thousands of patients, and his clinics operated successfully for decades.

Dr. Niels Ryberg Finsen also won a Nobel Prize for discovering that specific wavelengths of light could kill bacteria. He developed specialized lamps to treat Lupus vulgaris (a severe skin condition caused by tuberculosis). His work was so groundbreaking that in 1903, he received the Nobel Prize in Physiology or Medicine for his discoveries.

Now, you are probably asking: with such incredible success and positive health outcomes for patients, why isn't this used by doctors anymore? It is because the mass production of antibiotics in the 1940s—specifically streptomycin, which directly cured tuberculosis—replaced sun therapy. A pill replaced the sun.

In the latter half of the 20th century, as the link between excessive UV radiation and skin cancer (melanoma) became clearer, the medical narrative shifted entirely. Sunlight went from being viewed as a vital nutrient to a dangerous carcinogen, leading to the "total sun avoidance" guidelines dominant today.

The Modern Renaissance: More Than Just Vitamin D

While modern medicine focuses almost purely on Vitamin D, sunlight does so much more than that. Our bodies are completely hardwired to solar cycles. Sunlight isn’t just a trigger for a single vitamin; it acts as a complex hormonal regulator, a cardiovascular therapy, and an energetic nutrient.

Your Daily Heliotherapy Protocol

1) Sunrise (from sunrise to around 9:30 AM): The critical window you don't want to miss. This window contains a specific type of light spectrum called near-infrared. It also contains blue light, while harmful UV radiation is absent during this time due to the low angle of the sun.

Visible blue light penetrates your retinal ganglion cells, signaling the suprachiasmatic nucleus to suppress melatonin and raise cortisol to make you alert and awake. (This morning spike is a good thing—it's chronically elevated cortisol that becomes a problem!)

• The Protocol: Aim for 10–15 minutes of exposure within 30 minutes of waking up. And if you are incredibly busy in the morning, remember: every single minute counts!

2) Midday / Solar Noon (~11:00 AM to ~1:00 PM) The dominant type of rays during this window are called UVB. This is the only time of day when the sun is at a high enough angle for our bodies to synthesize Vitamin D. Additionally, midday sun lowers your blood pressure by stimulating the release of nitric oxide in your skin, which acts as a powerful vasodilator (meaning it relaxes and widens your blood vessels, allowing blood to flow more easily).

• The Protocol: Aim for 10–20 minutes of unprotected exposure on a large surface area (like your arms, back, or torso). The key is to get your dose and step into the shade before your skin begins to turn pink.

3) Late Afternoon to Sunset (Golden Hour to Dusk) As the sun approaches the horizon, harmful UV radiation drops back to zero. Instead, the sky becomes filled with long-wavelength infrared light. Unlike UV rays, which only hit the surface of your skin, this infrared light penetrates deeply into your tissues, muscles, and joints, stimulating your cellular powerhouses for better mitochondrial function. At the same time, the declining visible light signals your master clock to start preparing for nocturnal melatonin synthesis, winding your body down for sleep.

• The Protocol: Spend 15–30 minutes outdoors or take a walk during the sunset window to close the daily circadian loop and signal to your brain that the day is done.

The Golden Rule of Heliotherapy: The dose makes the medicine. The historic sun doctors never allowed their patients to burn. Burning is toxic: intentional, incremental exposure is medicine.

The Controversial Sunscreen Debate

You have probably seen a lot of influencers on the internet advising people not to use sunscreen, claiming that sunshine is medicine and cannot harm you. I have a different view on this. While sunshine is medicine, it has to be used carefully. I do not advise people to stay in the sun all day long, since UV rays can cause severe skin damage.

So let's be clear on this: while the sun is healing, it can absolutely be damaging. If I know that I will be out in the sunshine all day long, I will definitely use sunscreen. I prefer to use a non-toxic, mineral-based sunscreen that safely protects you and your family from burning.

One major concern with conventional sunscreens is that many of them contain synthetic chemicals. Once you apply the cream and step into the sunshine, these ingredients can be absorbed directly into your bloodstream. So yes, I am absolutely in favor of using sunscreen—but I strongly advocate for choosing a natural, mineral-based option.

Click here for my non-toxic, mineral-based sunscreen that is safe for the whole family.

Winter Solace: The Power of Red Light Therapy

During the winter, most of us don't get the benefits of sunshine, which we can really feel in both our mood and our overall health.

That is where red light therapy comes in. During those dark winter months, a red light device can mimic the healing, UV-free wavelengths of the early morning sun right inside your home. It penetrates deep into your tissues to stimulate your mitochondria (increasing cellular energy), which boosts your mood, supports immune health, and helps reduce winter stiffness when real sunshine is hard to find.

But don't pack it away when the weather warms up—I actually use my device during the summer as well. Even when the sun is out, many of us spend our days inside air-conditioned offices or homes, missing those prime morning wavelengths. Using red light therapy in the summer gives your skin an extra layer of cellular resilience, helps your muscles recover faster from summer outdoor activities, and reverses the cellular stress caused by too much intense midday UV exposure. It truly is a year-round game-changer for your health.

About the Author:

Beata is a registered nurse and health consultant for Dr. Clark Store. She is passionate about holistic health, with a strong focus on nutrition and addressing the root cause of chronic issues. If you have any questions, don't hesitate to reach out to her on substack or Instagram @wholisticbeata.