Red Light Therapy (RLT) is a non-invasive treatment that uses specific wavelengths of light, typically in the red (630 to 700 nanometers) and near-infrared (700 to 1000 nanometers) spectrums, to promote cellular health. These wavelengths are absorbed by the mitochondria, the energy centers of the cells, stimulating biological processes that support healing and regeneration. Proper preparation, particularly regarding garments worn, is necessary to maximize the therapeutic effect.
The Principle of Minimal Coverage
The primary goal for any RLT session is to ensure the light energy reaches the targeted skin and underlying tissues without obstruction. Clothing acts as a barrier that significantly diminishes the light’s intensity and absorption rate, even though a small amount of light can pass through thin fabrics. This reduction in light dose, often called “blunting” the effect, can render the treatment less effective, especially when deep penetration is desired.
For full-body treatments, the ideal scenario is to be completely nude to allow for maximum, unimpeded exposure across the entire surface area of the body. If garments are worn for comfort or modesty, they must be minimal, loose-fitting, and made of light-colored, thin, breathable fabrics like cotton or linen. Dark colors and thick materials, such as heavy knits or wool, must be avoided because they absorb and scatter the light, blocking therapeutic wavelengths from reaching the skin.
Tight-fitting clothing also presents a problem because it can limit the light exposure and potentially impede local blood flow, which works against the benefits of the therapy. Therefore, if a specific area is being targeted, such as the back or a joint, that area must be fully uncovered for the session to be effective. The choice of clothing should always prioritize exposing the entire treatment area directly to the light source.
Mandatory Protective Gear
While minimal clothing is the rule for the body, protective gear for the eyes is a necessary exception that must be worn for safety during most RLT sessions. Specialized protective eyewear, such as blackout goggles, is required because the high intensity of light from professional-grade devices can be uncomfortable and potentially damaging to the retina over time. This is particularly true when treatment involves high-power density light sources or near-infrared (NIR) wavelengths, which penetrate deeper than red light.
Near-infrared light, in particular, can pass through the eyelids, so simply closing the eyes may not provide sufficient protection with powerful devices. The need for eye protection is greatest when the eyes are within the direct beam window of the device, typically within two feet or less of the light source. Always follow the device manufacturer’s instructions, as protective eyewear is often supplied with the unit for a reason.
If an individual prefers to wear minimal undergarments during a full-body treatment, choosing light-colored, minimal coverage is acceptable. A brief covering over non-target areas, such as the genital region, is a reasonable compromise that maintains comfort without severely reducing overall efficacy.
Pre-Therapy Skin and Body Preparation
Ensuring the skin is clean before beginning any red light therapy session is necessary for optimal light penetration. Products on the skin, including makeup, sunscreen, lotions, and heavy moisturizers, act as a physical barrier that reflects, absorbs, or scatters the light. This interference diminishes the amount of therapeutic light that reaches the cells, reducing the overall efficacy of the treatment.
Before a session, the skin should be gently cleansed to remove all surface oils, dirt, and cosmetics, then thoroughly patted dry. Moisture on the skin can reflect the light, further impeding effective penetration. It is advisable to avoid using active ingredients like retinol or exfoliating acids in the 24 hours before a session, as these can increase skin sensitivity.
In addition to skin cleanliness, all metal jewelry must be removed from the treatment area before stepping into the device. Metal surfaces can reflect the light and may potentially heat up during the session, causing discomfort or leading to uneven light distribution. Staying adequately hydrated is also a general recommendation, as proper internal hydration supports overall cellular function and can help the body respond optimally to the photobiomodulation process.