HeraSphere #17: The light that fixed my deep sleep

Hi friends,

I'm back after a summer that can only be described as controlled chaos. Think: back-to-school season times three (high school, middle school, preschool—all different schedules), plus work, plus my daughter's Bat Mitzvah. I was running on fumes and couldn't unwind at night, even when I finally had the chance.

So when a friend recommended red light therapy, I nodded politely and ordered one. Then let it sit in the box for three weeks because honestly? I had no idea what the hype was about. But the first night I actually used it, my sleep tracker lit up with something I couldn't dismiss: my deep sleep jumped nearly 30%. One night could be a fluke. But it kept happening. That's when I fell into a research rabbit hole, and what I found was legitimately fascinating.

Redlight Therapy 101

Red light therapy—technically called photobiomodulation—uses specific wavelengths of light (typically between 630-850 nanometers) that penetrate your skin and get absorbed by your cells' mitochondria. They're the powerhouses that convert oxygen and nutrients into ATP (Adenosine Triphosphate), the energy currency your cells run on. Its like a rechargeable battery that powers every cellular function in your body.

Here's where it gets interesting for those of us over 40: our mitochondrial function naturally declines with age, particularly as estrogen drops. Research shows that when red and near-infrared light hit cytochrome c oxidase, an enzyme in your mitochondrial electron transport chain, it accelerates ATP production. Translation: the lights literally help your cells make more energy.

The Mitochondrial Connection

Think of your mitochondria as tiny solar panels inside every cell. Studies on organisms exposed to 670 nm red light show ATP increases ranging from 20% in the retina to over 50% in brain tissue. That's not a small bump—that's your cells running significantly more efficiently.

The peak effect happens 3-6 hours after exposure, with muscle cells showing a 200-350% increase in ATP synthesis compared to baseline. This delayed response explains why you might not feel an immediate buzz, but notice cumulative benefits over weeks.

Three Ways Red Light Shows Up for Women Over 40

Deep Sleep Architecture Changes

This is where my personal experience aligns perfectly with the research. Photobiomodulation appears to improve the brain's waste removal system—the glymphatic system—which is most active during deep sleep. Your brain essentially takes out the trash at night, clearing beta-amyloid and other metabolic waste that accumulates during the day.

A 2023 randomized controlled trial found that participants using red and near-infrared light exposure to the head and neck before bed reported improved self-reported sleep quality and perceived improvements in next-day function. The wavelengths used—660 nm, 740 nm, 810 nm, and 870 nm combined—seem to support melatonin production without suppressing it the way blue light does.

Research on elite female athletes showed that 30 minutes of whole-body red light exposure nightly for 14 days improved sleep quality scores and increased serum melatonin levels, with a strong correlation between the two. The beauty here is that red light doesn't just help you fall asleep—it appears to enhance the quality of the sleep you're getting.

Skin's Collagen Response

If you're noticing changes in your skin texture and elasticity (and who isn't after 45?), this is where red light gets really practical. Studies show that even low-level red and infrared light at just 0.3 J/cm² significantly increases the gene expression of hyaluronic acid synthase, elastin, and collagen types in human skin cells within 3-7 days.

The wavelengths penetrate to the dermis layer and stimulate fibroblasts—the cells that produce collagen and elastin—while also activating cytochrome c oxidase to boost ATP production in skin cells. More energy means your skin cells can do their repair work more efficiently.

A controlled trial of 128 participants found that over 90% showed reduction in wrinkle depth and surface roughness after 12 treatments, with ultrasound scans confirming increased collagen density in treated areas. These weren't dramatic before-and-after shots—these were measured, quantifiable changes in skin structure.

I can’t say my skin has changed from the red light therapy specifically, as I have been investing in lasers and microneedling at the same time (pre-Bat Mitzvah beauty routine could be a future issue!). I figure it can’t hurt and will continue to monitor results.

Energy Production at the Source

The fatigue piece is what intrigued me initially. Red light helps prevent a specific problem: when nitric oxide binds to cytochrome c oxidase, it gums up ATP production. Red and near-infrared light help dissociate that harmful binding, essentially unclogging your cellular energy production.

A 2024 study found that 670 nm photobiomodulation reduced blood glucose spikes by 7.5% following meals, likely because the increased ATP production demands more glucose consumption by cells. Your cells are literally using fuel more effectively.

Here is How I Started

I bought a portable red light panel and started with 10-15 minutes before bed. First spot: by the couch, where I could read under it for a few minutes each night. The warm red glow felt calming, not clinical. Once my sleep tracker confirmed the results weren't a fluke, I moved it right beside my bed. Now it's as automatic as brushing my teeth—just part of how I wind down.

There haven’t been any studies on at-home devices, but I do feel very confident in my own n of 1 experiment that the impact on sleep is real.

Look for devices that specify their wavelengths (630-660 nm for red, 810-850 nm for near-infrared) and their irradiance (aim for 20-100 mW/cm²). FDA clearance is a good sign but not always necessary for home devices. Panels, masks, and handheld devices all work—choose based on which body areas you want to target.

The science here is legitimate and growing. If you're dealing with sleep disruption, skin changes, or that midlife energy dip, red light therapy is an option worth considering or asking your doctor about.

I'm glad to be back. This slightly different format—shorter, more focused, more sustainable—means I can deliver more targeted deep dives on the topics you care about without disappearing for months at a time.

So tell me: what do you want to explore next? What's the health topic you're curious about, the symptom nobody's explaining well, or the wellness trend you're skeptical of but intrigued by? Hit reply. I'm building the next issues around what you actually want to know.

Lilly

PS. Please share this with a friend or family member who may benefit from improved sleep from red light therapy!

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Note: While I love diving deep into research and sharing what I've learned about women's health and wellness, I want to be crystal clear: I'm a passionate health advocate and researcher, not a medical professional. Think of me as your well-informed friend who does extensive homework – but not your doctor.

Everything I share in HeraSphere comes from careful research and personal experience, but it's meant to inform and inspire, not to diagnose or treat any medical conditions. Your body is uniquely yours, and what works for one person might not work for another. Always consult your healthcare provider before making significant changes to your diet, exercise routine, or wellness practices, especially if you have underlying health conditions or take medications.