Guest Blog: Getting Outside Gets Inside

By Scott Fisher (Kavod Board Chair) and Ben Green, co-authors of The Aging Wisely Project

It is a sad commentary on our current cultural worldview that sunlight is widely perceived to be harmful, a cancer-causing threat. But what does the research actually say? And does this research affect older adults differently than other people?

Spectrum: For starters, we should understand that sunlight is a complex combination of photons, with different wavelengths and properties. The sun is the original full-spectrum illumination, while both incandescent and LED lights emit, as one might expect, mostly visible-spectrum light.

Intensity: The other important variable is the intensity of light, measured in LUX units (a foot away from one candle): direct sun comes in at 100,000; a cloudy day at 1,000; a kitchen or office measures 500; and a living room only 50. That’s why you need to get outside.

UV: At one extreme is ultraviolet light (UV), whose wavelength is slightly shorter than visible violet. With regard to our health, UV is a mixed bag.

• It does cause sunburns, damages DNA, and triggers the aging of skin. It is also statistically associated with malignant melanoma, although, curiously, not with increased deaths from melanoma (because these cancers are mostly treatable).
• On the other hand, there are numerous health benefits: UV lowers the risk of hypertension, diabetes, atherosclerosis (hardening of the arteries), blood inflammation, and COVID infections. UV also stimulates Vitamin D synthesis in the skin. A large-scale study of 500,000 Brits, with a 12-year follow-up, found that frequent UV exposure lowered all-cause mortality by 14%, with cardiovascular deaths down 21% and total cancer mortality decreased by 13%. It gives one pause to reconsider the vast sums spent on sunscreen lotions. Just wearing light summer clothing blocks 80% of UV.

IR: UV radiation represents only about 3% of the sunlight that strikes the surface of the earth, while about 50% is infrared (IR), whose lightwaves are just beyond (longer) than visible reds. IR radiation is more predominant at the beginning and end of days, while UV is strongest when the sun is overhead. A thick cloud cover reduces IR significantly more than UV. In a recent superb Huberman Lab podcast, Dr. Roger Seheult touted the many benefits of IR radiation. Most severe and chronic diseases also involve mitochondrial dysfunction (mitochondria are the small organelles within a cell that produce the energy-generating chemical ATP). One aspect of aging is that we lose 70% of our mitochondrial functioning after age 40. Unlike UV, IR radiation passes through light clothing and the surface of the skin to penetrate deep into body tissues, where it significantly stimulates mitochondrial ATP synthesis.

Effects: The effects of improved mitochondrial functioning are pervasive, correlated empirically with sun exposure. Dr. Seheult cited statistics demonstrating that the greatest number of all-cause mortality comes soon after the shortest day of the year, and the lowest number of deaths occurs close to the longest days.

• People who live far north or south of the equator – where days are particularly short in winter – have higher overall mortality rates, particularly in mid-winter. In a study of almost 30,000 Swedish women, avoidance of sun exposure carried the same risk of premature death, as did smoking.
• There is well-replicated rigorous research that moderate IR exposure lowers the risk of cancer, heart disease, diabetes, hypertension, and it reduces blood lipids and chronic inflammation. IR increases immune system response to infections, such as influenza, COVID and pre-cancerous cells.
• On a sunny day, just 15 minutes outside can make a big difference. If you’re in a ‘green space’ with lots of grasses, leaves, bushes, and trees, you can receive two to three times the IR dose because plants reflect much of the IR that strikes them (notice that most leaves don’t get hot in the sun because of these reflective properties).

Red Light Therapy: There are many ‘red-light therapy’ devices now available – if you are considering them, be sure to carefully research IR wavelengths, dosage, safety, and therapeutic benefit. One study, utilizing an IR desk unit shining only on face, neck, and hands, proved to be quite therapeutic.

Forest Bathing? Dr. Seheult delighted in reminding us of the wisdom of the ancient beliefs that sunlight and fresh air promote convalescence. ‘Forest bathing’ has become a thing – the air around trees is infused with phytoncides that defend plants from bacteria, fungi, and insects. When inhaled by humans, they up- regulate immune functioning and lower stress levels, and reduce stress hormones. The beauty and serenity of such an environment further enhances these benefits, some of which are detectable by lab tests a month later. Furthermore, getting up with the sun (and out from behind the filtering effects of plate glass windows) helps to set your circadian rhythm, which can improve sleep patterns. Take home message: forests, parks and even golf courses soothe the soul, and the body. And early morning and late afternoon may be particularly beneficial.

Sweat Benefits: Dr. Seheult is a pulmonologist who treats many respiratory infections – he also reminded us about how previous generations treated patients with hot baths and hot packs, as if to ‘sweat out’ infections. It’s been recently discovered that body temperatures a little over 100 degrees Fahrenheit actually accelerate the production of interferon, a powerful anti-viral protein. Maybe we’ve been a little too quick to reduce our fevers with aspirin, Tylenol, and Advil. And maybe the saunas so favored by Scandinavians and Russians are more therapeutic than we’ve realized.

Conclusion: As spring has sprung, we encourage everyone to get away from your screens, go outside and enjoy the benefits of the sunshine that so amply surrounds us. Residents at Kavod Senior Life have a myriad of ways to get outside, whether it be on the sunlit patio areas, in the resident gardens, on the nearby walking paths in Cherry Creek or on the many benches and sitting areas surrounding the campus. Come for a visit and see for yourself!

Ben and Scott – https://theagingwiselyproject.com/