What Is Red Light Therapy and Its Purpose: A Complete Guide

Red light therapy (RLT) – sometimes simply called red light treatment or even just red therapy – is a non-invasive treatment that exposes the body to specific wavelengths of red and near-infrared light. If you’ve been curious about this trend and wondered what red light therapy is for or what its purpose is, the simple answer is that it aims to stimulate the body’s natural healing processes using low-level light energy.

What Is Red Light Therapy?

Red light therapy (RLT) is a therapeutic technique that uses low-intensity red light (and often near-infrared light) to stimulate biological responses in the body. In practice, this means shining red or near-infrared light on the skin to promote healing and rejuvenation. The treatment is sometimes referred to by other names, such as:

• Low-level laser therapy (LLLT)
• Photobiomodulation
• Cold laser therapy

How It Differs from Other Light Therapies

Unlike ultraviolet (UV) light used in tanning beds (which can damage skin) or blue light used for acne, red light is in the visible spectrum and is very low energy. It does not burn the skin or cause significant heat. In fact, RLT is sometimes called “cold laser” therapy because the light isn’t strong enough to heat tissues noticeably.

Key characteristics of red light therapy:

• Wavelength range: Typically ~620–700 nanometers (visible red) and 800–900 nm (near-infrared)
• Penetration depth: About 1–2 millimeters into the skin
• Heat generation: Minimal to none
• Safety profile: Very gentle and non-invasive

According to research, at these low wavelengths the light penetrates the skin without the harmful effects of UV radiation, making red light therapy a safe and gentle treatment option.

How Does Red Light Therapy Work?

Red light therapy is thought to work through several key mechanisms:

Cellular Energy Enhancement

When the body is exposed to red and near-infrared light, the light photons can penetrate through the skin and reach our cells’ mitochondria – often called the “powerhouses” of the cell. The mitochondria absorb these light wavelengths and produce more adenosine triphosphate (ATP), which is the energy currency of the cell.

In essence, RLT gives cells a bit of extra energy. With this increased energy, cells may function more efficiently, repair damage faster, and rejuvenate themselves.

Beneficial Cellular Effects

By strengthening the mitochondria and boosting ATP, red light therapy can trigger a cascade of beneficial effects:

• Increased circulation: Better blood flow brings more oxygen and nutrients to tissues
• Higher collagen production: Improves skin structure and elasticity
• Reduced inflammation: Helps with pain relief and tissue recovery
• Enhanced cellular repair: Faster healing and regeneration processes

Important Distinction

It’s important to mention that RLT is not the same as using a heating lamp or sunlight. The wavelengths in red light therapy are very specific and do not significantly heat the tissue. Near-infrared light (often included in RLT devices) doesn’t cause the skin to feel hot, unlike far-infrared waves used in heating lamps or saunas. This means the mechanism of action is through cellular stimulation rather than thermal (heat) effects.

How Is Red Light Therapy Administered?

LED Light Panels and Lamps

These are flat panels or lamps studded with dozens of red (and often near-infrared) LED bulbs. You might sit or stand a few inches away from the panel so that the light shines on your skin. Many spas and clinics have full-body red light therapy beds or panels (similar in appearance to a tanning booth) that bathe you in red light for a set time, usually about 10–20 minutes per session.

Handheld Devices and Wearables

There are smaller devices like wands, masks, or pads that contain red LEDs:

• Facial red light masks: Popular for beauty treatments targeting facial skin
• Handheld red light wands: Can be applied to specific joints or spots for pain relief
• LED therapy pads: Flexible devices that can be wrapped around body parts

Medical Laser or LED Systems

In clinical settings, dermatologists or physical therapists use more powerful red or infrared lasers. These are still low-level (non-ablative) lasers specifically designed for therapy, not to cut or burn like surgical lasers, but to stimulate healing in tissue.

Red Light Saunas

A red light sauna is essentially an infrared sauna that also incorporates red light therapy panels. Key differences from traditional saunas:

• Temperature: Operate at lower temperatures (around 110–140°F vs 150–200°F)
• Focus: Deliver red and near-infrared light to the body
• Comfort: More comfortable for those sensitive to heat
• Benefits: Combine detoxifying relaxation with cellular rejuvenation

Typical Treatment Experience

No matter the device, a typical RLT session is:

• Painless and quick
• 10-20 minutes duration
• Minimal sensation (mild warmth at most)
• Eye protection recommended (goggles to protect from bright light)
• Very safe with almost no side effects when used properly

What Is Red Light Therapy Used For?

1. Skin Health and Anti-Aging

Perhaps the most popular use of red light therapy is for improving skin appearance:

• Wrinkle reduction: Stimulates collagen production for smoother skin
• Fine lines and age spots: Reduces visible signs of aging
• Scar fading: Helps fade scars and stretch marks
• Skin texture: Improves firmness through boosted collagen and fibroblast activity
• Chronic skin conditions: May help with psoriasis, rosacea, and eczema by reducing inflammation

2. Acne and Skin Healing

Red light, sometimes in combination with blue light, is effective for:

• Acne treatment: Calms inflammation and promotes healing of acne lesions
• Wound healing: Accelerates repair of skin wounds and may reduce scar formation
• Medical applications: Used in hospitals for stubborn wounds or ulcers

3. Hair Growth

Red light therapy can stimulate hair follicles:

• Pattern hair loss: Studies show improved hair growth in androgenic alopecia
• Hair thickness: Users often see thicker hair in areas of thinning
• Follicle stimulation: Energizes follicle cells and prolongs the growth phase

4. Pain Relief and Inflammation

Red and near-infrared light are frequently used for:

• Joint pain: Relief for arthritis, rheumatoid arthritis, and tendinitis
• Muscle soreness: Reduces post-workout soreness and inflammation
• Carpal tunnel syndrome: Short-term symptom relief
• General pain management: Increases circulation and decreases oxidative stress

5. Muscle Recovery and Performance

Athletes and fitness enthusiasts use RLT for:

• Faster recovery: Energizes cells and improves blood flow to muscle fibers
• Reduced soreness: Decreases delayed onset muscle soreness (DOMS)
• Enhanced performance: Some studies show improved strength return after exercise
• Anti-inflammatory effects: Minimizes exercise-induced tissue damage

6. Wound Healing and Tissue Repair

Clinical applications include:

• Surgical incisions: Promotes faster healing of post-surgical wounds
• Burns and injuries: Accelerates natural healing processes
• Diabetic ulcers: Helps with non-healing wounds
• Cancer treatment support: May help heal oral tissue damaged by chemotherapy

7. Other Potential Applications

Early research is exploring RLT for:

• Neurological health: Potential cognitive function improvements
• Vision health: Possibly slowing myopia progression in children
• Thyroid function: Improvements in hypothyroidism
• Mood and sleep: Better sleep patterns and mood enhancement
• Memory and brain function: Neuroprotective effects when applied to the head

Infrared Light Therapy and Red Light Therapy

Key Differences

Infrared Light refers to light beyond the visible spectrum, divided into:

• Near-infrared (NIR): Closest to visible red light, behaves similarly to red light
• Mid-infrared: Middle range of infrared spectrum
• Far-infrared (FIR): Furthest from visible light, primarily experienced as heat

Red Light Therapy:

• Uses visible red light (~620-700 nm) and near-infrared (~800-900 nm)
• Minimal heating of tissues
• Focuses on cellular stimulation and photobiomodulation

Infrared Sauna Therapy:

• Uses far-infrared light to generate heat
• Intentionally warms the body for circulation and detoxification
• Reaches deeper into tissues and raises core temperature

The Connection in Practice

Many modern wellness setups combine both:

• Red light saunas: Provide far-infrared heat plus red/near-infrared light
• Combination devices: Emit both red (660 nm) and infrared (850 nm) wavelengths
• Complementary benefits: Cellular rejuvenation plus relaxation and circulation

Choosing the Right Approach:

• For cellular rejuvenation: Red or near-infrared devices (RLT/photobiomodulation)
• For whole-body relaxation: Far-infrared sauna therapy
• For comprehensive benefits: Combined red light sauna systems

Safety and Considerations

General Safety

Red light therapy is generally very safe with:

• Low risk of side effects when following proper guidelines
• No significant heat generation
• Non-invasive and painless treatment
• Suitable for most skin types

Potential Side Effects

Overdoing treatment (excessive exposure times or too-high intensity) could potentially cause:

• Skin irritation
• Temporary tightness
• Eye strain if proper protection isn’t used

Who Should Exercise Caution

• Pregnant women: As a general precaution
• People on photosensitizing medications
• Those with active cancer in treatment areas
• Individuals with certain eye conditions

Best Practices

• Follow device instructions for exposure time and distance
• Use eye protection during treatment
• Start with shorter sessions and gradually increase
• Consult healthcare providers for serious medical conditions

Conclusion

Red light therapy has emerged from niche technology to a mainstream wellness and therapeutic tool. By now, you should have a clear understanding of what red light therapy is and what it’s used for. In essence, RLT uses specific red and near-infrared light wavelengths to energize cells and promote healing in the body.

The Purpose of Red Light Therapy

The applications span from:

• Cosmetic improvements: Smoother skin and fuller hair
• Pain management: Natural relief for various conditions
• Athletic performance: Faster recovery and reduced soreness
• Medical applications: Wound healing and tissue repair

Important Considerations

While many users and studies report significant benefits, it’s important to approach red light therapy with balanced expectations:

• Scientific evidence: Still considered preliminary for many applications
• Individual results: May vary from person to person
• Safety profile: Very low risk when used properly
• Complementary approach: Best used alongside, not instead of, conventional medical care

The Future of Light Therapy

Red light therapy stands as a fascinating example of how light, one of nature’s fundamental energies, can be used to support human health and well-being in innovative ways. With ongoing research and growing user experiences, red light therapy’s full potential will become clearer in the years ahead.

Whether you’re interested in it for beauty, pain relief, or general health, understanding the basics – from what red light therapy is to how it overlaps with infrared therapy – will help you make informed decisions about incorporating this promising treatment into your wellness routine.