Visible light from the sun is nearly a thousand times more intense than the artificial light from our devices and may trigger pigmentary skin changes, particularly for people with skin of color and those who have melasma or dark spots from acne.

Visible light from the sun plays a significant role in causing pigmentary skin changes, particularly in people with skin of color, according to information presented at AAD VMX 2021.

“We know from decades of research that unprotected exposure to ultraviolet light from the sun can lead to skin cancer and premature skin aging — such as wrinkles and age spots — and how to protect ourselves,” says study author says Henry W. Lim, MD, FAAD, former chair of the department of dermatology at Henry Ford Hospital in Detroit, in a news release. “However, visible light from the sun hasn’t been as widely researched, so we’re continuing to explore the full spectrum of sunlight to better understand its impact and ultimately identify ways the public can protect themselves.”

Visible light makes up about 50 percent of the sunlight that reaches the earth’s surface. People are exposed to visible light from the sun and through lamps and blue light that’s emitted from electronic devices; however, Dr. Lim says that unlike visible light from the sun, the visible light individuals are exposed to indoors does not cause any damaging effects to the skin.

“Even with prolonged exposure to a computer screen — eight hours a day, five days a week — research shows that the visible light emitted from our devices is not intense enough to negatively impact our skin,” says Dr. Lim. “However, the visible light from the sun is nearly a thousand times more intense than the artificial light from our devices, and we’ve come to realize that this outdoor visible light is triggering pigmentary skin changes, particularly for people with skin of color and those who have melasma or dark spots from acne.”

A catalyst for researchers’ understanding of how visible light affects the skin differently than UV light was discovered after noticing that individuals with skin of color developed intense and long-lasting pigmentation upon exposure to visible light. For example, dermatologists noticed that their patients with melasma who used broad-spectrum sunscreens — those that protect against the sun’s harmful ultraviolet A (UVA) and ultraviolet B (UVB) rays — continued to experience pigmentary skin changes despite the sunscreen’s protective effects against UV light.

To protect against visible light from the sun, Dr. Lim recommends many of the same tips as protecting against UV rays — seek shade and wear protective clothing, including a long-sleeved shirt, pants, a wide-brimmed hat and sunglasses. However, he explains that there is a difference in sunscreen protection for visible light.

“I typically tell my patients to look for a broad-spectrum sunscreen that says “tinted” on the label and has an SPF of 30 or higher,” says Dr. Lim. “Tinted sunscreens contain iron oxide, which research shows helps protect people’s skin against the negative effects of visible light.”