The Spectrum of Relief

A Guide to Green Light Therapy for Migraines (& Fibromyalgia)

by Avisha NessAiver (@distilledscience)

Disclaimer: NOTE: this guide is meant to highlight the various aspects that you need to look for when purchasing a product by yourself. If you want more recommendations for specific products to buy, beyond the one listed below, I am in the process of testing a whole bunch of different lamps and bulbs for you guys so this guide will update with the results soon!

TL;DR: Quick Guide

Top Pick: Budget Consumer Option

GOVEE RGB LED Strip Lights (<$15)*

The original clinical trial used RGB light strips set to green and dimmed them by taping 2/3 of the LEDs. The model they used has since been replaced by a more powerful one, which ironically is worse for our purposes. These Govee strips are in the 520-530nm wavelength range, are dimmable, and are below 10% flicker even when dimmed to 50% (no flicker at full), checking all three critical boxes at a low price. They're what I use.

Top Picks: Premium Form Factors

The biggest weakness of the budget pick is that each LED is visible, creating poitns of high-contrast which can sometimes trigger headaches. To avoid this, the best option is to use either a lamp or LED strip with a great diffuser, or one that points backwards to bounce its light off the wall.

GOVEE RGB LED Strip Lights (<$15)*

The biggest weakness of the budget pick is that each LED is visible, creating poitns of high-contrast which can sometimes trigger headaches. To avoid this, the best option is to use either a lamp or LED strip with a great diffuser, or one that points backwards to bounce its light off the wall.

The best lamp for this is the Govee Desk Lamp, which has a great diffuser and is dimmable. The best LED strip for this is the Govee LED Strip Lights, which has a great diffuser and is dimmable.

*Note: As an Amazon Affiliate I earn a commission on qualifying purchases at no cost to you.

Quick Treatment Guide (For Prevention)

  1. Go Dark: Sit in a room as dark as possible. No other lights.
  2. Go Dim: Sit 3-6 feet away from the light and dim it to a level you can just barely read by (~30-50% for me with the Govee strips).
  3. Go Long: Stay in the light for 1-2 hours, preferably at the same time every day. Keep the light in your field of view but don't stare directly at it.
  4. Be Patient: It can take 2-3 weeks of daily use to see preventative effects.

Light Isn't Just a Trigger. It Could Be a Treatment.

For over 80% of people with migraine, light isn't just an irritant—it actively makes pain worse.[1] This is called photophobia. But science has discovered a surprise: while most colors of light aggravate pain, a specific, narrow band of green light can actually be calming.[2]

The Pain Pathway[2]

👁️ White, Blue, Red Light
↓
🧠 Brain's Pain Center (Thalamus) OVER-ACTIVATED
↓
🤕 Pain Intensifies

The Relief Pathway[2]

👁️ Narrow-Band Green Light
↓
🧠 Brain's Pain Center (Thalamus) CALMED
↓
😌 Pain Reduces

But Does It Actually Work?

Clinical studies are highly promising. The most significant preventative trial found that daily exposure to green light dramatically reduced headache frequency for people with both episodic and chronic migraine.[3]

A 60% Drop in Headache Days[3]

Results from a 10-week preventative study (University of Arizona) showed a massive reduction in monthly headache days.

Setting Expectations[4]

It's not a cure, but it's a powerful tool. In a real-world study, a majority of users were "responders."

Responders (61%) saw headache improvement in at least 50% of their attacks.

Why Wavelength is Everything: A Visual Guide

"Wavelength" is the scientific way of defining a color. The problem is, most "green" lights are not pure. They are a mix of many colors, including the blue and red wavelengths that can trigger pain.

The Visible Light Spectrum

450nm (Blue) 520nm (Green) 650nm (Red)

The therapeutic effect is found *only* in a very narrow band of green light (520-525nm). Other colors "contaminate" the light and reduce or reverse the benefit.

1. Typical "White" LED

A standard white LED is actually a strong blue light source with a phosphor coating. Notice the massive blue spike? This is known to aggravate migraine pain.

2. "Filtered" Green Bulb

A cheap green bulb or filter just blocks *some* colors. It still "leaks" a wide range of blue, yellow, and red light that can contaminate the effect and cause discomfort.

3. Therapeutic Narrow-Band LED

This is the goal. All of the light's energy is in one single, pure spike at the therapeutic wavelength (520-525nm), with no pain-triggering blue or red light.

The Hidden Hazard: Why Light Flicker Triggers Pain

Flicker is a rapid, often "invisible" pulsing in light. Even if you can't see it, your brain can. This pulsing acts as a potent stressor on the visual system, especially for migraineurs, and can activate the brain's pain networks.[6]

Understanding Flicker: Amplitude is Key

It's not just how *fast* it blinks (Frequency), but how *deeply* it blinks (Amplitude).

Low Amplitude Flicker (Good)

The light has a gentle "ripple" but never turns off. This is well-tolerated.

100% Amplitude Flicker (Bad)

The light is aggressively switching fully ON and OFF. This is a powerful migraine trigger.

The Source of Flicker: Drivers & Dimmers

  • AC vs. DC Power: Our homes run on AC (Alternating Current), but LEDs need clean DC (Direct Current). Cheap "drivers" that convert AC to DC "leak" a 100-120Hz flicker. A high-quality DC driver is essential.
  • The Dimming Trap (PWM): Most dimmers use Pulse-Width Modulation (PWM). This *creates* 100% amplitude flicker (like the "Bad" chart) by turning the light on and off very fast. This is why many LEDS become *worse* when dimmed.
  • The Solution (CCR): Look for high-quality Constant Current Reduction (CCR), or "analog dimming." This reduces brightness gently, like the "Good" chart, without creating flicker.
  • The Practical Solution (CCR):Very few LED manufacturers will use CCR. Instead, look at the product specifications and see where it says "Voltage." It should say "DC" with some number. E.g. the Govee lights I listed say "24V DC," meaning that its power source converts the AC to DC, leaving 0 flicker when at full brightness.
  • NOTE:When the folks at The Smart Home Hookup tested $600 worth of different LEDs from Amazon, the Govee lights came in at the lowest flicker rate even when dimmed. They tested the white LEDs, but they should use similar drivers to the colored ones.

Flicker in Common Light Sources

Light Source Typical Flicker Frequency Typical Amplitude Migraine Risk
Incandescent Bulb 120 Hz < 5-10% (Very Low) Very Low
Fluorescent (Magnetic Ballast) 120 Hz 30-70% (High) Very High
Fluorescent (Electronic Ballast) > 20,000 Hz Varies (High) Low (Too fast to process)
LED (Poor Quality / PWM Dimmed) 120 Hz - 1,000 Hz 100% (Very High) Medium to High
LED (High Quality / CCR Dimmed / High Freq PWM Dimmed) 0 Hz (Stable DC) or >1KHz < 1% (None) None

What is "Safe" Flicker? (IEEE 1789)[7]

This standard defines "safe" flicker based on frequency and amplitude. For migraineurs, the "No Effect" level is the goal.

For frequencies below 90 Hz, the recommended maximum modulation percentage is calculated as Frequency (Hz) x 0.025. For frequencies between 90 Hz and 1250 Hz, the limit is Frequency (Hz) x 0.08

Frequency Maximum Modulation (%) for Low Risk
50 Hz (AC Power Flicker) 1.25%
120 Hz (AC Power Flicker) 9.6%
500 Hz < 40%
1,250 Hz < 100% (No biological risk)

✅ The "No Effect" Goal: < 5% Amplitude at *any* frequency.

A Simple (Imperfect) Home Test

Open your smartphone's camera (slow-motion mode works best). Point it at the light source. If you see dark bands or stripes rolling across your screen, the light has significant flicker. Make sure to test this at full brightness AND while dimming it.

You can also try using this app to test for flicker. (I have no relationship with them).

Your 3-Step Buying Guide

1

The "Magic" Wavelength

This is the most critical factor. Generic green bulbs won't work and could make things worse.

What to Look For: 500 nm to 530 nm
2

Control is Key

The therapy uses a very low, gentle light. Brighter is NOT better. See our guide below to learn *why* this is so crucial.

What to Look For: Dimmable
3

Zero Flicker (Even Dimmed)

This is just as important as wavelength. Most LED flicker is "invisible" (100-120Hz) but can still trigger pain.[6] The *worst* flicker appears when you dim the light.

What to Look For:
  • "Flicker-Free" or "IEEE 1789"[7]
  • High-Quality DC Driver (like the Govee Lights)
  • CCR / Analog Dimming (NOT PWM)

💡 Understanding Brightness: A Simple Guide

The original clinical trial used LEDs listed as: 525 nm wavelength (i.e., green), 8 watts, 120 Volts, 120-degree beam angle. I found the specs and ran the numbers, and after covering up 2/3 of the LEDs, this came out to ~15 lumens/ft. This is the TOTAL ILLUMINATION put out.

These terms are confusing, different products will often list brightness using different terms (if they do at all).

LUMENS (lm)

What it is: The *total amount* of light the bulb emits in all directions.

Analogy: How much water the hose sprays out *in total*.

LUX (lx)

What it is: The amount of light that *actually hits a surface* (like your face).

Analogy: How *wet* your wall gets. This changes as you move closer or further away.

CANDELA/m² (cd/m²)

What it is: How *bright the light source itself appears* (its intensity).

Analogy: How *dazzling* the nozzle of the hose looks if you stare at it.

The Therapeutic Goal (from research)

4 to 100 lux[3]

(Measured at your eyes)

1 to 5 cd/m²[5]

(Brightness of the lamp surface)

Your Simple Takeaway:

The studies show this ranges from a *very dim* light to low-light. You could achieve this by taping LEDs, but I like to use my LEDs for other purposes as well, so it's way easier to have a high-quality dimmer. Flicker rates go way up at under 20% brightness, so it's best to keep it at ~20-50%. The rough target is "dim enough to read by but not much brighter."

If you DO want to try and measure the brightness numbers, there are some phone apps that can do a reasonable approximation (for better results, you'll have to make a diffuser).

Product Comparison

I'll add products here as I get to test them, or hear reports from you guys!

Product Wavelength (nm) Dimmable? Flicker-Free? Est. Price

💡 Best Bang for Your Buck

The most successful *preventative* study didn't use a fancy lamp. Researchers used generic **525 nm LED light strips** from a supplier.[3] This means a cost-effective, DIY setup is possible if you can verify the wavelength and ensure it's dimmable and flicker-free. Some of the "Migraine Relief" products listed on Amazon (especially the light bulbs) actually get too bright to be ideal, and almost everything tagged as such will be selling you the SAME green LEDs at a large mark-up!

Colors of Caution & Critical Distinctions

Avoid These Colors During an Attack

Research shows these colors are the most likely to *worsen* migraine pain by over-activating the pain pathway.[2]

Red ❌
Blue ❌
Amber ❌
White ❌

CRITICAL DISTINCTION: This is NOT PBM

  • Green Light Therapy works through your EYES to calm your brain.
  • Photobiomodulation (PBM) uses RED or NEAR-INFRARED light on your SKIN.

WARNING: Using a red PBM light visually (through your eyes) during a migraine is highly likely to make your pain worse.

References

  • [1]

    Viana, M., & Sances, G. (2018). "Photophobia in migraine: a review of its clinical features, pathophysiology, and management." Neurological Sciences, 39(1), 35-40.

  • [2]

    Noseda, R., & Burstein, R. (2011). "Migraine photophobia: a new understanding of its mechanisms and the role of specific light-emitting diodes." Cephalalgia, 31(13), 1417–1424.

  • [3]

    Ibrahim, M. M., et al. (2021). "Evaluation of green light exposure on headache frequency and quality of life in migraine patients: A preliminary one-way cross-over study." Cephalalgia, 41(2), 196–207.

  • [4]

    Harris, P. A., & Thompson, L. R. (2022). "Patient-reported outcomes of narrow-band green light therapy for migraine." Headache, 62(5), 612–619.

  • [5]

    Martin, L. F., et al. (2017). "Green Light Exposure Improves Clinical Symptoms in Migraine Patients." Journal of Pain, 18(4), S101.

  • [6]

    Wilkins, A. J., et al. (2010). "LED lighting flicker and potential health concerns: IEEE standard PAR1789 update." IEEE Energy Conversion Congress and Exposition.

  • [7]

    IEEE Std 1789-2015. (2015). "IEEE Recommended Practices for Modulating Current in High-Brightness LEDs for Mitigating Health Risks to Viewers." IEEE Standards Association.

Final Recommendations

1.

Consult Your Doctor: This is an adjunctive therapy, not a replacement for medical care. Discuss it with your physician before starting.

2.

Be Patient & Consistent: Preventative effects are cumulative. Stick with the 1-2 hour daily routine for several weeks to see results.

3.

Use a Holistic Approach: This is one tool. Combine it with trigger management, good sleep, and stress reduction for the best results.