Sunlight — at the Right Time — Has No Substitute 🌞

At LeafSide, we’re unabashed health & nutrition nerds 🤓 who scan the Internet daily, for practical, evidence-based health info that works — and that are worth sharing with family, friends, and LeafSiders everywhere!

July is UV Awareness Month ☀️ 😎, quite apropos given the abundance of sunlight and warm weather for the northern hemisphere.

It’s now quick and easy to check the UV Index (and safety) with our smartphones 📱, but did you know that the UV Index was first developed rather late, in Canada 🇨🇦 in 1992 — a little over 30 years ago? From there and then, it was quickly adopted by various governments around the world, and by 2008, the American Academy of Ophthalmology named July to be UV Safety Awareness month.

You likely know all the standard advice now about UV, but here’s a recap from the American Academy of Dermatology to protect your skin from short-term damage, and long term skin aging & cancer risks:

  1. Seek shade when you can ⛱️
  2. Wear sun-protective clothing 👒 🧢
  3. Use a broad-spectrum, water-resistant sunscreen, SPF 30 or higher 🧴

UV is termed a complete carcinogen, i.e. it can initiate skin cancers, and accelerate their growth. Yuck.

Given that, why not just stay out of the sun all the time?

There’s Much More In Sunlight, than UV

Besides major benefits of being outdoors, like the immunity-boosting of forest bathing, getting some sunlight helps expose our entire body to all the other forms of light in sunlight, especially infrared light.

Spectrum of solar radiation, on Earth
By Robert A. Rohde – CC BY-SA 3.0,

Looking at the above, the left-axis represents the power-level, while the horizontal axis is the wavelength of the sun’s light, from short to long.  UV is on the left with high-energy short wavelengths; visible light that our eyes can see follows; and then the lower-energy, long-wavelengths of infrared (IR) light follow.

Infrared light is about HALF of all the energy from the sun 🌞, that reaches the Earth! i.e. if you added up the red areas in the chart above, the infrared portion would be about half of all the red areas.

Given how clever life is generally, about using any and all available energy, might our cells use all that IR light in important ways?  The research increasingly says YES.


Seeing the Power of Invisible Infrared

One of our favorite sources is MedCram, on YouTube with over 1.5 million subscribers; they go in-depth on timely health topics of all sorts, and always with a careful, current-science, and clear presentation. 👌

Last year (2022), we shared how MedCram examined the mystery of why supplementing with vitamin D isn’t significant in reducing covid or flu severity 🤧, despite low levels of it being tied to severe covid outcomes.

How could that be?  As the science cliche goes, correlation is often not causation.  In short, being short on vitamin D meant that not only were the unfortunate patients not taking a vitamin D supplement, they weren’t getting enough IR exposure either — which looks to be a major factor in our mitochondrial health, which depends in turn on intracellular melatonin levels, which IR sunlight boosts.

To recap:

  1. Low vitamin D levels and severe covid are highly correlated.
  2. But supplementing with vitamin D doesn’t reduce infection severity.  🤔
  3. Another big association, is that covid/flu season (winter) starts sooner and is worse in higher latitudes; thus the greater sunlight when you live further south, must bring other benefits.  🌞
  4. Sunlight has large amounts of infrared radiation (IR), which is used by mitochondria to produce subcellular melatonin in every cell of our body! In fact it’s 95% of our melatonin; our pineal gland only produces 5%.  🤯
  5. That subcellular melatonin is a powerful antioxidant, which mops up pro-oxidants before they damage our cells.  Otherwise, damaged cells are much more susceptible to covid and other pathogens.
  6. So get exposed to IR from the sun regularly!


Since that MedCram video, there’s been still more direct evidence that IR light is important for human health; a small but significant randomized controlled clinical trial (RCT) used an IR vest, and found faster recovery from covid, for patients getting the IR exposure:

Short on time? Here’s the skinny:

  • A randomized controlled trial used Near Infrared LED lights for the treatment of hospitalized COVID-19 patients. The light, delivered via a LED vest emitting at 940 nanometers, was tested on 30 inpatients between the ages of 50 to 80.  A control group also wore a vest that emitted no IR light.
  • The IR-treated group had significant improvements in oxygen flow intake, partial oxygen saturation, and blood markers: White blood cell counts decreased in the treatment group, indicating improved health, while lymphocyte counts, which are important for fighting infection like viruses, doubled.
  • The study was small (30 patients) but significant; so expect more research in this area!
  • Note too that the IR here was just one wavelength, at 940nm. Artificial IR sources like “red light”  panels are usually limited to 1 or 2 IR wavelengths. But natural sunlight brings a much wider range of IR wavelengths.

So we should get some sun every day, when possible.

But how do we get the sun’s beneficial IR light, without the harmful UV?

How to Get the Sun’s Infrared Light to Recharge Subcellular Melatonin, While Avoiding UV

In short: Go outside, in the few hours after sunrise, or before sunset! 🌅 👍

Infrared radiation can penetrate through clothes, AND it bounces off of leaves and grass very well. 🌴 So you don’t even need to be in direct sunlight, as long as you’re catching the natural bounce, and not behind glass.

MedCram advised in a related video (see below), that you can get plenty of IR sunlight while avoiding skin-damaging UV light, AND help your circadian cycle too — by being outside after sunrise and before 9 or 10am, or after 4 or 5pm before sunset. ✅

So long as you feel that warmth from the sun, that’s the sure sign you’re getting infrared sunlight.

As for how you dodge harmful UV light:  When the sun is at a low angle, like during sunrise or sunset, sunlight has a longer path to travel through the atmosphere. The result? Most of the bad, short-wavelength UV rays get scattered and absorbed before reaching your skin.  Whereas the longer wavelength IR rays can pass through the longer path with much less interference. 🌞 😊

Nothing New Under the Sun…

For most of human existence, people knew the sun brought many health benefits.  It’s only in “modern” societies, with indoor homes, workplaces, and cars, that we may forget our connection to the outside world.

To repeat MedCram’s advice from a notable health reformer, Ellen G. White (pictured), from more than 100 years ago:

“The feeble one should press out into the sunshine as earnestly and naturally as do the shaded plants and vines.  The pale and sickly grain blade that has struggled up out of the cold of early spring, puts out the natural and healthy deep green after enjoying for a few days the health-and-life-giving rays of the sun.  Go out into the light and warmth of the glorious sun, you pale and sickly ones, and share with vegetation its life-giving, health-dealing power.”

Want to Learn Even More About Light-as-Medicine?

MedCram made a much longer video about the role of light and sunlight in health, that’s well worth watching too:

One More Life-changing Tip…

At LeafSide, we love health hacks, so here’s one more: Get your infrared sunlight, AND maximum-efficiency blood circulation exercise, at the same time: Do the high-intensity “Nitric Oxide Dump” workout outdoors!

This is how you’ll “feed two birds with one scone” just check this out: Nitric Oxide Routine/Workout and try it outside, with fresh air and sunlight!