Henry Lim, MD: New Data on Photoprotection for All Skin Phenotypes

This week, an HCPLive interview with Henry Lim, MD, featured a discussion regarding Lim’s 2023 Winter Clinical Dermatology conference presentation and its main points about photoprotection for different skin phenotypes.

Lim is a dermatologist and is Senior Vice President for Academic Affairs at Henry Ford Health System in Detroit.

“Essentially, this is becoming a very important topic or what I call personalized photo protection,” Lim said. “And very similar to personalized medicine, where you tailor the treatment for the individual group or individual person. This is the same concept, that photo protection should be tailored according to the skin types.”

Lim went on to note that there is a broad spectrum of various kinds of effects resulting from sunlight, the most famous being ultraviolet B radiation.

Another type that was less well-known until recently was that of visible light radiation, which Lim described as highly impactful.

“For the longest time visible light was considered to be inert,” he said. “Our groups together with others had shown that actually visible light does have photobiological effects. Specifically, we showed that visible light, if we shine it on the skin of dark skinned individuals, would induce pigmentary alteration that is quite intense and it would also be long-lasting for quite a few weeks in terms of duration.”

Lim also added that these same effects were found not to occur in lighter-skinned individuals in the research he cited.

“And the clinical significance of that is that, obviously, this would implicate the role of visible light on pigmentary changes that occur primarily in dark-skinned individuals,” he said. “Specifically, post-inflammatory hyperpigmentation. People with acne, for example, in light-skinned individuals…some red blemishes left behind would fade away very quickly. Not so with dark skinned individuals. After the acne is gone, very frequently, the patient would be left with a very dark mark on the skin that could last for quite a few months.”

He also described the skin condition known as melasma, which he states occurs more commonly in darker-skinned phenotypes.

“We all have our clinical experience that patients with melasma would tell us ‘I use sunscreen all the time, still my melasma in the summer tends to get worse,’” Lim explained. “Again, then that, most likely, is the contribution of visible light making the melasma worse...But all of the active ingredients of sunscreen in the US are formulated so as to protect against the effect of UV light but would not protect against the effects of visible light.”

To find out more about Henry Lim’s research and Winter Clinical presentation, view the interview segment above.