Articles

Evidence based

Evidence Based

This article is based on scientific evidence, written by experts and fact checked by experts.

Our team of licensed nutritionists and dietitians strive to be objective, unbiased, honest and to present both sides of the argument.

This article contains scientific references. The numbers in the parentheses (1, 2, 3) are clickable links to peer-reviewed scientific papers.

The Best Red Light Therapy Devices—A Clinical Take

Written by Dr. Michael Ruscio, DC on March 18, 2025

Written by Dr. Michael Ruscio, DC on March 18, 2025 — Reviewed by Kellie Blake

• Intro to Red Light Therapy|
• RLT Devices|
• Our Recommendations|
• RLT for Fatigue and Aging|
• RLT and Thyroid Health|
• RLT Protocol|
• Managing Medication|
• Safety|

Red light therapy (RLT) is gaining popularity for its wide range of health benefits. These include improved energy levels and mood, better skin, reduced hair loss, and thyroid health support.

As a functional health practitioner who has seen firsthand the impact of RLT on my clients, I find it to be a particularly promising tool for a lesser-known use—managing Hashimoto’s and hypothyroidism.

But whether your main concern is thyroid health or overall wellness, it’s important to know how to make the most of this easy-to-use and effective therapy.

Below, we’ll explore the best red light therapy devices, how to use red light therapy, and the results you can expect.

Understanding Red Light Therapy

Red light therapy (also known as photobiomodulation (PBM), cold laser, or low-level laser therapy (LLLT) involves wavelengths of red and near-infrared light being shone at the body.Red and near-infrared wavelengths are in the 620–1,400 nanometers (nm) range 1 2 and don’t create heat. This makes RLT a safe and practical therapy for at-home use.

Red light therapy works by stimulating an enzyme called cytochrome C oxidase in the mitochondria. Mitochondria are often called the powerhouse of cells because they make energy from the food you eat. Cytochrome C oxidase is needed for the mitochondria to make energy (ATP). 

The downstream effects of this include:  

1. Better energy levels (our bodies produce more ATP or adenosine triphosphate, which is energy at the cellular level) 2 3. 
2. Improved nitric oxide function, a molecule that improves blood flow 4.
3. Higher free radical production, which means the body naturally increases its production of antioxidants to protect itself 5 6 7. 

Regarding the third point above, RLT works like a mild stressor, similar to exercise or cold stress that helps strengthen the body’s defenses against inflammation.

Fun fact! RLT was originally studied by NASA for its beneficial effects on plant growth and wound healing in space 8.

What to Look for in a Red Light Therapy Device

Red light for therapeutic use can be emitted by either a laser or an LED (light-emitting diode). 

Laser light penetrates deeper and is more powerful—professionals may use laser wands to treat small, precise areas, such as pain points in specific muscles. However, LED lights cover larger surfaces with a more diffuse light distribution and are generally better suited for home use, including treating thyroid and skin conditions.

While LEDs may require slightly longer treatment times compared to lasers, the difference isn’t significant. 

Misleading marketing can make it seem like you need to shell out thousands of dollars on LED light therapy devices, such as fancy red light LED mask devices. However, that simply isn’t the case.

All you really need is an FDA-approved device with the appropriate red light wavelengths, and you’ll have something effective.

Here’s a more detailed checklist of what to look for in a RLT device (and what doesn’t matter as much):

• FDA Approval: Ensures safety and quality control.
• Wavelength: The most effective range for thyroid support is 810–850 nm, as used in clinical studies. Most devices—not just the expensive ones—offer a wider range of wavelengths, allowing you to address multiple health concerns.
• Size & Coverage: Larger red light therapy panels are ideal for full-body or larger treatment areas, while smaller, handheld devices work best for targeted treatment, such as the face or thyroid.
• Power Output: Higher irradiance ensures deeper light penetration and better results. Irradiance is measured in milliwatts per square centimeter (mW/cm²) and is more important than total wattage, which doesn’t indicate how efficiently the light penetrates.

Best Red Light Therapy Devices: Our Recommendations 

If you follow the above guidelines, you should be able to find an LED device that suits your needs and budget. But for a more specific recommendation, these two devices are our clinic’s current top picks:

Red Light Therapy for Aging, Mood, Energy, and Hair Health

The benefits of red light therapy aren’t just theoretical—this is one therapy where cell-level activities translate into real-life results.

Pain and Fatigue

People with fibromyalgia, a chronic condition characterized by widespread pain and fatigue, had reduced pain and fatigue when given whole-body RLT 9.

Digging into this study (a randomized controlled trial) a bit more shows that just one red light therapy session improved pain threshold.

After 10 sessions of RLT for 5 minutes on each pain point,  participants had pain relief at multiple tender points, reduced symptoms such as anxiety, depression, fatigue, and sleep difficulties, and improved overall quality of life.

Combining red light therapy with regular exercise and stretching had the most significant impact, improving pain scores and overall well-being. 

Mood

While more research is needed, early findings indicate that RLT could be a promising, low-risk therapy for managing depression. 

A systematic review noted that people with depression showed noticeably improved mood after red light was shined close to the head 10.

RLT can penetrate the skull and may boost brain energy production, influencing pathways linked to depression. 

Skin Rejuvenation

Red light therapy is popular for its anti-aging effects on the skin, but it is more than a trend. The available science seems to support RLT for improving skin health. 

When RLT was applied to the skin, older people with wrinkles had improvements in 11  12

• Skin hydration
• Skin elasticity 
• Collagen density

These are before-and-after pictures of a woman in her 70s who used at-home facial red light therapy treatments for 20 minutes daily for 12 weeks. Since these results are taken from a peer-reviewed medical journal, we can have some confidence that they haven’t been manipulated with filters or lighting 13.

Some of my clients who tried red light therapy have also noticed similar improvements in fine lines, blemishes, and skin tone using at-home devices. For my clients with chronic skin issues, such as acne and eczema, understanding the importance of the gut-skin axis is foundational for improving their skin health.  For specific advice, speak to your dermatologist. 

Hair loss

A review showed that people with genetic hair thinning had reduced hair loss after RLT was applied to the scalp 14.

The review included a total of 966 patients across 36 studies. The meta-analyses showed that photobiomodulation treatments were significantly effective compared to controls. Specifically:

• Alopecia Areata (AA): Both ultraviolet and infrared light therapies were effective.
• Androgenetic Alopecia (AGA): Both red light and infrared light therapies were effective.

In a study on women with androgenic alopecia, 25 minutes of RLT (655nm) on their scalp every other day for 16 weeks increased hair growth by 37% compared to the placebo group 15. 

How Red Light Therapy Supports Thyroid Health

Some of my clients with thyroid dysfunction have successfully used red light therapy to ease symptoms like fatigue and brain fog, as well as to reduce their reliance on thyroid hormone medication.

Since the thyroid gland is located close to the skin, red light can easily penetrate it, helping to reduce inflammation. This reduction in inflammation likely contributes to improved hormone production and overall thyroid function.

Red Light and Thyroid: Clinical Evidence

There isn’t a whole stack of studies examining the effects of red light therapy (RLT) on underactive thyroid conditions, but the research that does exist is super promising.

Hashimoto’s Disease

Hashimoto’s is an autoimmune condition that attacks thyroid cells and often precedes thyroid underactivity. 

One study found that 16:

• 3 months of RLT combined with selenium, iodine, and vitamin D supplementation allowed 29% of patients to discontinue their levothyroxine (thyroid hormone) medication). 
• Additionally, levels of thyroid antibodies (TPO antibodies), which are a hallmark of the condition, significantly decreased by 433 points!

Hypothyroidism

Clinical hypothyroidism occurs when the autoimmune attack on the thyroid gland progresses to the point where the gland is no longer producing sufficient hormone levels, slowing metabolism. 

A placebo-controlled study found that 17:

• After 10 sessions of RLT, nearly half of the participants with hypothyroidism were able to stop taking thyroid medication
• Those in the placebo group saw no change in their condition.
  

How Much and How Long? Our Thyroid RLT Protocol

One of the most common questions people ask me about RLT is how often and for how long they should use the therapy. For uses like general wellness, healthy aging, and skincare, we don’t have extensive data other than to say that RLT appears safe, so using it a couple of times a week—or even every day—is not a problem. However, for thyroid conditions, we have research to guide us, which suggests that you can take breaks in treatment.

More specifically, follow-up studies indicate that the thyroid benefits wear off after about 11 months, so once-yearly repetitions of treatment blocks are warranted 18.

Here is the full thyroid RLT protocol that works best for our clients.

You should check and follow the usage and safety guidelines for your own device, as the required duration and distance may vary. Remember, too—check your thyroid hormone levels from time to time while using the device.

Support With Thyroid Supplements

What we’ve found at the clinic—also borne out by studies— is that underactive thyroid conditions will usually respond best when red light therapy and thyroid-supportive nutrients are used together 16 19. 

Here’s the full supplement schedule we use in the clinic alongside red light therapy:

Managing Thyroid Medication While Using Red Light Therapy

I advise my clients with Hashimoto’s or hypothyroidism that they may temporarily experience symptoms of thyroid overactivity—such as palpitations or impaired sleep—as a side effect of improvement. This occurs when the body starts producing more of its own thyroid hormone, potentially leading to an excess when combined with ongoing medication.

Since 30–50% of individuals who use red light therapy (RLT) for thyroid health experience significant benefits—sometimes enough to require less medication—it’s important to monitor thyroid levels regularly.

If RLT is effective, you may need to adjust your thyroid hormone dosage (levothyroxine/LT4) over time and, in some cases, gradually reduce or stop medication under medical supervision. Always consult your healthcare provider to ensure a safe and balanced approach.

RLT Safety Considerations

RLT is generally very safe, with rare side effects. These could include 

• Temporary minor skin redness or irritation 
• Dark spots on the skin (hyperpigmentation)

While no studies show harm, it’s best to avoid RLT during pregnancy 9. And if you currently have a cancer diagnosis, you should check with your doctor about using RLT as the evidence as to whether it may help or harm is conflicting 26 27.

There’s no good information on whether it’s okay to look directly at red LEDs or whether you should use eye protection. If you have concerns, you should check with your doctor or wear eye goggles.

Red Light Can Spell Relief

In summary, red light therapy is a versatile, non-invasive treatment that offers a wide range of benefits—from boosting energy and improving skin health to supporting thyroid function. 

When combined with targeted supplements and used according to tested protocols, RLT can be a powerful tool for managing thyroid conditions and enhancing overall wellness. However, if you need advice on tailoring a treatment to your specific need, we’re always here to help.

The Ruscio Institute has developed a range of high-quality formulations to help our clients and audience. If you’re interested in learning more about these products, please click here. Note that there are many other options available, and we encourage you to research which products may be right for you. The information on DrRuscio.com is for educational purposes only. It is not a substitute for professional medical advice, diagnosis, or treatment.