O que é a terapia de luz vermelha? Benefícios e riscos

What is red light therapy?

Red light therapy (RLT) is a treatment that uses low-level wavelengths of red or near-infrared light to stimulate cells in the body. Also known as low-level laser therapy (LLLT) or photobiomodulation (PMB), it is used to support skin healing, reduce inflammation, and improve circulation.

The treatment involves exposing your skin to a lamp or device that emits red light. Unlike ultraviolet (UV) rays, red light does not cause burns or tanning, and it penetrates the skin without causing damage.

Red light therapy is thought to work by stimulating mitochondria, the energy-producing parts of our cells. When cells absorb red and near-infrared light, mitochondrial function may improve, allowing cells to repair and regenerate more efficiently.

This cellular activity can trigger various biological processes, such as increased blood flow and the release of anti-inflammatory compounds. These responses may help explain some of the reported benefits of red light therapy.

Research into red light therapy is ongoing, but some early studies suggest it may offer a range of benefits.

Isso inclui:

• Skin health - RLT is commonly used in dermatology for reducing fine lines, wrinkles, and acne. It may help boost collagen production and improve skin texture.¹

• Cicatrização de feridas - some evidence suggests red light therapy can speed up wound healing and reduce scarring.²

• Alívio da dor - RLT may help ease muscle and joint pain by reducing inflammation and promoting circulation.³

• Hair growth - it has been explored as a treatment for hair loss conditions such as androgenetic alopecia.⁴

• Saúde mental - there is some interest in red light therapy as a possible treatment for seasonal affective disorder (SAD), although more research is needed.⁵

Generally, red light therapy is considered safe for most people when used correctly. Side effects are rare and typically mild, such as temporary redness or irritation at the treatment site. However, it’s not suitable for everyone, and certain groups should be cautious.

These groups include:

• Pregnant or breastfeeding people - safety during pregnancy or breastfeeding hasn’t been fully studied.

• People with active cancer - RLT may not be safe for existing cancerous tissue. Consult your doctor first.

• Those taking photosensitising medicines - for example, some antibiotics, acne treatments, chemotherapy can make your skin more sensitive to light.

• People with eye conditions or light sensitivity - use protective eyewear to avoid irritation or damage.

• People with epilepsy - flashing or pulsing lights may trigger seizures in photosensitive people.

• People with open wounds or severe skin conditions - RLT may worsen some skin issues. Seek medical advice first.

Can you use red light therapy while pregnant?

There is limited evidence on the safety of red light therapy during pregnancy. While the treatment is non-invasive and doesn’t use radiation, it’s best to avoid use during pregnancy unless advised by a healthcare professional.

Can red light therapy cause cancer?

There is no evidence that red light therapy causes cancer. In fact, it uses non-ionising light that does not damage DNA.⁶ However, more research is needed on long-term use, especially in people with a history of skin cancer.

Is it safe for cancer patients?

Red light therapy is not typically used to treat cancer itself, but it may be used in supportive care to relieve side effects such as oral mucositis - a common side effect of chemotherapy. People with cancer should consult their doctor before starting any form of light therapy.

Is red light therapy bad for your eyes?

Direct exposure to red light is not generally harmful, but eye protection is often recommended during treatment, especially when using high-powered devices. Prolonged exposure to intense light can cause discomfort or irritation.

Red light therapy is available in a variety of settings:

• Clinics and spas - many dermatology clinics and wellness centres offer red light therapy as part of aesthetic or therapeutic treatments.

• GP or specialist referral - in some cases, red light therapy may be recommended for specific medical conditions such as chronic wounds.

• Red light therapy at home - a growing number of people are using red light therapy devices at home. These include LED panels, handheld devices, and facial masks. While home use can be convenient, it’s important to use devices safely and follow manufacturer instructions.

When choosing a home device, look for products that meet UK safety standards and have clear guidance on usage and eye protection.

Can you get red light therapy if you talk to your GP?

Red light therapy is not commonly offered through NHS GPs as a standard treatment, but your GP can help guide you depending on your condition.

Here's how it typically works:

• For medical conditions - for example, chronic wounds, oral mucositis, joint pain - your GP might refer you to a specialist. This could include a dermatologist, physiotherapist, or pain clinic who may consider red light therapy as part of your treatment plan, especially in hospital or clinical settings.

• For cosmetic or wellness uses - for example, anti-ageing, acne, hair loss - red light therapy is usually accessed privately. In this case, your GP won’t prescribe it but can still offer advice on whether it’s safe for you based on your health history.

So, while you may not get red light therapy directly through your GP, speaking to them can be a useful first step - especially if you have underlying health conditions or are considering at-home devices.

Red light therapy is a non-invasive treatment that uses low-level red and near-infrared light to support skin health, ease pain, and promote healing. While early research is encouraging, many of its claims still need stronger evidence.

For most people, red light therapy is considered safe, especially when used as directed. However, it’s not suitable for everyone, and those who are pregnant, have cancer, or have eye conditions should seek medical advice before starting treatment.

Whether you try red light therapy at a clinic or opt for red light therapy at home, it’s important to manage expectations and approach the treatment as part of a broader health plan - not a miracle cure.