Red light therapy is not tanning. The two use completely different types of light, work through different biological mechanisms, and produce different results. Red light therapy will not darken your skin the way a tanning bed or sun exposure does.
Why Red Light Doesn’t Tan Your Skin
Tanning happens when ultraviolet (UV) light, specifically UVA (315–400 nm) and UVB (280–315 nm), triggers your skin cells to produce more melanin, the pigment that darkens your skin as a protective response to DNA damage. Red light therapy operates at entirely different wavelengths, typically between 620 and 700 nm for red light and 750 to 1,100 nm for near-infrared light. These wavelengths fall outside the ultraviolet range and do not trigger the melanin production pathway.
Red light therapy has minimal direct impact on melanin production. Melanin levels are primarily influenced by UV light, not red or near-infrared light. So if you’re standing in a red light therapy panel or lying in a red light bed, your skin is not receiving the type of energy that causes a tan.
How Red Light Therapy Actually Works
Instead of damaging skin cells to trigger a pigment response, red light therapy works at the cellular energy level. Red and near-infrared wavelengths are absorbed by an enzyme in your mitochondria called cytochrome C oxidase, the last step in your cells’ energy production chain. When this enzyme absorbs red light, it becomes more active, increasing oxygen consumption and energy output. This boost in cellular metabolism is why red light therapy is used for wound healing, skin rejuvenation, and reducing inflammation.
The biological effect is essentially the opposite of what happens in a tanning bed. UV light in tanning beds causes direct DNA damage to skin cells, which is what triggers both the tan and the long-term skin cancer risk. Red light therapy does not cause this type of DNA damage. In clinical studies, patients receiving red light treatments to their face reported softer, smoother skin, less redness, and lighter dark spots, essentially the reverse of the darkening you’d see from UV exposure.
The Equipment Looks Similar
Part of the confusion is understandable: red light therapy beds look almost identical to tanning beds. They’re the same shape, you lie in them the same way, and some facilities even convert old tanning beds by swapping out the UV bulbs for red light panels. But the bulbs inside are producing fundamentally different energy. Tanning beds emit UVA rays. Red light beds emit visible red and invisible near-infrared light. Your body can feel near-infrared as gentle warmth, but it’s not the same heat or radiation profile as a tanning session.
The FDA treats these as entirely different product categories. Tanning beds are regulated as electronic products under specific UV-emitting device standards. When a tanning bed’s UV lamps are replaced with red light panels, the FDA considers it a new type of device that falls under different regulatory classifications and requires separate clearance before it can be marketed. They are not interchangeable in any regulatory or medical sense.
One Exception Worth Knowing
While red light therapy won’t give you a tan, it can affect skin pigmentation in certain people. The American Academy of Dermatology notes that people with darker skin tones are more sensitive to visible light, including red light, than those with lighter skin. This sensitivity can lead to hyperpigmentation, where patches of skin become darker than the surrounding area. These dark spots can be more intense and longer-lasting than pigmentation changes caused by UV light. This is not a tan in the traditional sense. It’s an uneven pigmentation response, and it’s a reason people with deeper skin tones should pay attention to how their skin reacts during red light therapy sessions.
Can You Use Both?
Some people use red light therapy alongside sun exposure or tanning, reasoning that the skin-repair benefits of red light might offset UV damage. Red light therapy does support cellular repair processes and reduce inflammation, which is why it’s studied in the context of wound healing. But it does not provide any protective barrier against UV radiation the way melanin or sunscreen does. If you tan in a UV bed and then do a red light session, you’re getting two separate biological effects: UV-induced DNA damage and pigment production from the tanning bed, and enhanced cellular energy production from the red light. One does not cancel out or substitute for the other.
The bottom line is straightforward. If you want darker skin, red light therapy won’t do it. If you want the cellular and skin health benefits associated with red light therapy, a tanning bed won’t provide them. Despite looking alike, these are two completely different technologies doing completely different things to your skin.