What Skincare Should You Actually Use Under Your LED Light?

By Allison Marks LE - Director of Education

There is a lot of noise in skincare right now, but the most effective routines are almost always the most understated.

At LightStim, our expertise lies in light therapy and LED technology. Because we hold ourselves to an uncompromising standard, we choose to keep our skincare collection highly curated. We only introduce a product when our community requests it, and only when we can deliver something truly exceptional.

That dedication is the foundation of LightStim PhotoSerum.

While the formulation itself is comprehensive and beautifully balanced, it was custom formulated around a patented molecule called SFC (Disodium Succinoyl Farnesylcysteine), aligning perfectly with our light therapy philosophy of calming, restorative care.

Behind its silky, cushiony texture is a science-first formula designed to instantly increase surface hydration, leaving a plumped, smooth feeling that complements your LED treatment. Below, we look at the thoughtful science behind its dermatologist-tested, hypoallergenic formulation, and why it is so well-tolerated by sensitive skin.

SFC: The Princeton-Developed Calmer

If you’ve spent any time reading skincare labels, you know niacinamide is the widely celebrated standard. We love it too—it is a phenomenal multi-tasker known for helping with a wide variety of skin conditions. But instead of relying solely on standard ingredients, PhotoSerum features a patented hero molecule developed by researchers at Princeton University called SFC (Disodium Succinoyl Farnesylcysteine).

Everyday environmental stressors can trigger biological pathways that lead to visible redness and surface distress. Clinical evaluations show SFC is designed to calm and soothe these pathways by inhibiting IL-8 and TSLP production in epidermal cells, helping to quiet the cellular stressors triggered by common surface microbes.

And while niacinamide is highly effective for general barrier support, SFC actually outperforms it. In a rigorous, double-blind 12-week clinical study, SFC clinically outperformed niacinamide across the board, showing superior improvements in hydration, texture, and overall skin radiance. Best of all, safety and toxicology evaluations confirm that SFC is non-irritating and non-sensitizing, making it well tolerated by even the most delicate skin.

Ergothioneine: Supporting Mitochondrial Energy

The visible vitality of your skin is driven by cellular energy (ATP). To support this process, our formula incorporates Ergothioneine, a high-performance amino acid that acts as a dual-action cellular protector. Inside the cell, it works to defend against environmental stressors by neutralizing free radicals to help protect mitochondrial membrane integrity, while supporting the natural pathways that transport fatty acids for efficient energy production.

Its efficacy lies in its natural compatibility with human biology. While many topical antioxidants can struggle to absorb deeply enough to be effective, skin cells possess specialized transport systems called OCTN1 transporters. These act as dedicated pathways, allowing Ergothioneine to be naturally assimilated and concentrated where it is needed most including within the cell, its nucleus, and its mitochondria.

This targeted defense is reflected in its clinical performance. It demonstrates an Oxygen Radical Absorbance Capacity (ORAC) score of 61,000 (four times higher than benchmark botanical antioxidants like Coffeeberry), offers lipid peroxidation defense superior to CoQ10, and actively helps inhibit MMP-1—the enzyme triggered by UV exposure that can degrade collagen. By helping to quiet this collagen-degrading enzyme, Ergothioneine works to protect and support collagen, defending the skin matrix to seamlessly complement the restorative benefits of your LED treatment.

The Hydration Matrix: Propanediol, Glycerin & Sodium Hyaluronate

In cosmetic chemistry, the base of a serum is just as important as its active ingredients. When a base is unbalanced, it can easily leave a heavy, tacky residue that sits on top of the skin. PhotoSerum relies on skincare’s most trusted moisture pillars, pairing them in a thoughtfully balanced, synergistic matrix.

The foundation of this matrix is a partnership between Pure Glycerin and 100% plant-derived Propanediol (Zemea®). Glycerin is a gold-standard humectant, but on its own, it can feel heavy and sticky. By pairing it with bio-based Propanediol in a precise, synergistic ratio, we neutralize the tackiness entirely, leaving a weightless, smooth finish while delivering deeper, longer-lasting moisture than glycerin alone. 

This hydration matrix is anchored by Sodium Hyaluronate, the renowned moisture-binding molecule that instantly elevates surface moisture and holds water to the skin for a juicy, plump, refreshed appearance. In rigorous clinical patch testing on over 200 subjects, this bio-based hydration system demonstrated zero irritation, proving its absolute skin affinity for even the most sensitive skin.

By focusing on a few uncompromising ingredients—SFC, Ergothioneine, and an advanced hydration base, PhotoSerum helps support the skin barrier, soothe the appearance of redness, and deliver restored skin without irritation.

Dermatologically tested, hypoallergenic, and formulated for harmonious skin compatibility because advanced skin care should be just as thoughtful as the light therapy it accompanies.