Red Light Therapy and Blood Pressure | LightTherapy.no
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Red Light Therapy and Blood Pressure
Your doctor checks your blood pressure. Tells you it's a bit high. Maybe gives you that look. Maybe doesn't. Either way you drive home thinking about it, and then life gets in the way and three months pass and you haven't really done anything about it. Does that sound familiar?
Red and near-infrared light therapy (rødlysterapi) may genuinely support healthier blood pressure - not by some vague "reduce inflammation" mechanism but through a very specific biological process involving nitric oxide, the molecule your blood vessels use to relax and widen. Research from teams including Massachusetts General Hospital shows that photobiomodulation (fotobiomodulasjon) can increase the availability of this molecule in your vascular tissue, and the effect is real enough that it's showing up consistently across multiple studies. It's not a replacement for medication if your doctor has prescribed it. But as a supportive daily tool? The science is worth understanding.
Your Blood Vessels Are Not Pipes
Most people think of their blood vessels as basically plumbing. Tubes that carry blood around. Passive. Mechanical. Just... there.
They are nothing like that.
The inner lining of every blood vessel in your body - the endothelium - is living tissue. It's one of the most metabolically active surfaces in your entire body. It responds to your nervous system, to your hormones, to physical pressure, to oxidative stress, and yes, to light. It produces a signalling gas called nitric oxide (NO), which tells the smooth muscle around your vessels to relax. When those muscles relax, the vessel widens. When it widens, blood moves through with less resistance. Blood pressure drops. Heart doesn't have to work as hard. Downstream, you get less arterial stiffness, less clot risk, better oxygen delivery to tissue.
When the endothelium stops producing enough nitric oxide - which is called endothelial dysfunction - this whole system starts going wrong. Vessels stay tighter than they should. Pressure climbs. And the kicker is that nobody talks about this in terms of light, even though light is one of the inputs that directly drives nitric oxide availability in your vasculature.
That's the gap this post is filling.
So What Does Red Light Actually Do Here
There are two mechanisms and I want to explain both because together they make a pretty compelling case.
The first one: your skin and vascular tissue contain stored forms of nitric oxide - chemical compounds that hold onto NO until something releases it. Sunlight does this. Specifically, the red and near-infrared end of the solar spectrum does this photochemically, meaning the light itself triggers the release without needing any enzyme or any supplement to make it happen. Your body has been building this storage pool, and light is the key that opens it.
The second one is about your mitochondria. Inside the endothelial cells lining your vessels, the enzyme cytochrome c oxidase (this is the main photoreceptor in your mitochondria) can get inhibited by nitric oxide under stress conditions. It's a bit like someone putting a hand over your car's air intake - the engine is still there but it's not running properly. Red and near-infrared light photodissociates that inhibitory NO, clears the blockage, and lets the mitochondria run properly again. ATP production goes back up. The endothelium recovers its function. It starts producing nitric oxide correctly through its own enzymatic pathway again.
Two completely different mechanisms. Both triggered by the same light. Both pushing blood pressure in the right direction. That's not nothing.
A 2023 review in the journal Nitric Oxide by Kashiwagi and colleagues at Massachusetts General Hospital went through the evidence on photobiomodulation and nitric oxide signalling and concluded that near-infrared light improves endothelial function by increasing bioavailable NO in a dose-dependent way. You can read the whole thing here if you want to go deeper: https://pubmed.ncbi.nlm.nih.gov/36462596/
What the Bigger Picture Research Shows
In 2025 a systematic review and meta-analysis in the Journal of Clinical Medicine pulled together all available clinical trial data on photobiomodulation for hypertension management. The findings: possible reductions in systolic blood pressure, diastolic blood pressure, and heart rate across multiple trials. The authors were honest that the certainty is still low and the trials have methodology limitations. I appreciate that kind of honesty in research, by the way. It means they're not overselling it.
What "low certainty" actually means in this context is: the signal is real and consistent, but we need bigger, better designed trials to be sure of the size of the effect. The mechanism is well understood. The animal data is solid - a 2024 study in Lasers in Medical Science (Oishi et al.) showed red light at around 660nm preventing blood pressure increases in an obesity-induced hypertension model, with normalised nitric oxide levels and improved endothelial function: https://pubmed.ncbi.nlm.nih.gov/38165554/
Animal models aren't humans. I know. But when the mechanism makes sense at the cellular level AND the animal data points the right way AND the human trials are showing a consistent signal even in small studies, you'd be daft to ignore it entirely.
Grounding Fits Into This Too
I can't talk about nitric oxide and vascular health without bringing up grounding (jording), because they connect through the same root problem: oxidative stress in the endothelium.
When you make direct skin contact with the earth - barefoot on grass, a grounding mat, a grounding sheet - free electrons transfer from the Earth's surface into your body. These electrons are potent antioxidants. They reduce oxidative stress in exactly the tissue we've been talking about, the endothelium. Less oxidative stress means better nitric oxide production. Better nitric oxide production means healthier blood pressure.
I use both. Red light in the morning, grounding in the evening (or outside when the terrace isn't actively trying to freeze me). They're not competing approaches - they're working on the same problem from slightly different angles.
If you want to look at grounding and PEMF options alongside your light therapy, they're here: https://lighttherapy.no/collections/harmony-pemf-and-grounding-materials
For Us in Norway - the Winter Blood Pressure Problem
Blood pressure tends to run higher in winter. This is documented. The standard explanation is cold weather causing vasoconstriction. And yes, cold does that. But I think there's something else going on that almost nobody is talking about.
In Norway specifically, we spend months with almost no solar red and near-infrared spectrum hitting our skin. The sun is either not there or so low in the sky that the atmosphere filters out most of what we need. And we're inside under artificial lighting that is mostly blue-spectrum LEDs with essentially zero near-infrared output. So the photochemical nitric oxide release mechanism I described above? That's running on empty from October to March for most people.
Add cold-induced vasoconstriction on top of a months-long light-driven nitric oxide deficit, and you've got a real seasonal blood pressure problem that has nothing to do with diet or exercise. This is why I think light therapy (lysterapi) isn't just a wellness nice-to-have for us here - it's genuinely compensating for a biological gap that our environment is creating.
The Practical Bit - What to Actually Do
If you're taking this seriously, consistency is the thing that matters. One session does nothing in particular. Daily or near-daily use over weeks and months is where the cardiovascular research shows effects. Think of it the same way you'd think of exercise - one run doesn't fix your fitness, but six months of regular running absolutely does.
For blood pressure specifically, the chest, neck, and wrists are sensible areas to focus on because of the density of large vessels close to the surface. That said, full body sessions with a larger panel address the whole vascular system rather than just one part of it, and I find those more useful overall.
One thing I'll say directly: do NOT buy cheap underpowered devices for this. I have sent panels back after testing them with a spectrometer and finding they were putting out a fraction of what was advertised. The research uses devices that actually deliver meaningful irradiance to your tissue. A toy-spec LED gadget at half the power won't do what the studies show. There are too many cowboys in this space in 2026 and I'd rather tell you that plainly than have you waste money.
You can see what we stock at https://lighttherapy.no/collections/red-light-panels - and if you want something more targeted and portable for specific areas, there's also https://lighttherapy.no/collections/portable-and-specialist
This post is educational and not medical advice. If you have diagnosed hypertension or are on blood pressure medication, talk to your doctor before changing anything. The research is real and I've linked it all so you can read it yourself, but I'm not a doctor and I'm not treating you - I'm just telling you what the science says.
FAQ
Can red light therapy lower blood pressure? Research suggests it can support healthier blood pressure by triggering nitric oxide release from vascular tissue, which causes the vessels to relax and widen. Multiple clinical trials show possible reductions in both systolic and diastolic pressure. The evidence is consistent in direction but still needs larger, better-designed trials to pin down the size of the effect. Right now it's best understood as a meaningful supportive tool rather than a standalone treatment.
How does red light therapy affect blood vessels? It works through two mechanisms. First, it photochemically releases stored nitric oxide from compounds in your skin and vascular tissue - no enzyme needed, just light hitting the right molecules. Second, it restores mitochondrial function in endothelial cells by clearing the inhibitory nitric oxide that was blocking cytochrome c oxidase, which lets those cells produce their own nitric oxide properly again. Both mechanisms improve vasodilation and blood flow.
Why is blood pressure often worse in winter in Norway? Cold causes vasoconstriction, yes. But there's a light component too. The red and near-infrared solar spectrum that normally drives photochemical nitric oxide release from skin is largely absent during Norwegian winters. Most indoor lighting doesn't compensate - office LEDs and home lighting are blue-heavy and near-infrared deficient. So you're months into a nitric oxide deficit by the time February comes around, which sits on top of the cold-related vasoconstriction. Red light therapy directly addresses the light-driven part of this.
Kan rødlysterapi hjelpe med høyt blodtrykk? Forskning tyder på at rødt og nær-infrarødt lys kan støtte sunnere blodtrykk ved å utløse frigjøring av nitrogenoksid fra blodårevev, noe som får blodårene til å slappe av og utvide seg. Kliniske studier viser mulige reduksjoner i blodtrykket. Det er best forstått som et støttende verktøy ved siden av, ikke som en erstatning for medisinsk behandling.
How often should I use red light therapy for blood pressure support? Daily or near-daily use over weeks to months is what the research uses. One session isn't going to move the needle. Think of it like exercise - the benefit is cumulative and consistency is what actually works. Ten to twenty minutes daily is a reasonable protocol to start with.
Does grounding help with blood pressure too? Yes, and through a related mechanism. Grounding transfers free electrons from the Earth's surface into your body, which reduces oxidative stress in the endothelium - the same vascular lining that produces nitric oxide. Less oxidative stress, better nitric oxide production, better vascular function. It's not the same as red light therapy but it's working on the same underlying problem. I use both.
References: Kashiwagi et al. (2023) - Photobiomodulation and nitric oxide signaling. Nitric Oxide, 130:58-68. https://pubmed.ncbi.nlm.nih.gov/36462596/
Oishi et al. (2024) - Long-term effects of photobiomodulation on blood pressure in obese rats. Lasers Med Sci, 39(1):20. https://pubmed.ncbi.nlm.nih.gov/38165554/
PBM in Hypertension Management - Systematic Review (2025). J Clin Med, 14(19):6716. https://www.mdpi.com/2077-0383/14/19/6716
Related: https://lighttherapy.no/blogs/english/morning-red-light-therapy-and-blood-sugar-what-nobody-tells-you