Our results

80% of skin aging and damage comes from exposure to light radiation. Yet, the majority of sun protection still focuses only on UV rays. At Substance Of Light®, we made a different choice: to study and measure the effects of the entire light spectrum on the skin (UVA, HEV, visible light) from day one. Not as a marketing angle. As a scientific requirement.

Each product we formulate is subjected to rigorous testing protocols that go beyond market standards. We evaluate protection against all daily exposures—UV, blue light (HEV), and pollution—through complementary methods: in vivo and in vitro UVA/UVB tests, transmittance measurements for visible light (380–450 nm), as well as tests on human skin cells (HaCaT).

Because the skin is exposed to much more than just the sun, we believe effective protection cannot simply be claimed: it must be measured across the entire light spectrum.

Here are the results for our products, in full transparency.

1. THE PROTECTIVE HYDRATING FLUID

Blue light protection

Our fluid absorbs up to 27% of the HEV spectrum in the most energetic wavelengths, those that penetrate deepest into the skin. On the curve, this translates into low transmittance from 380 nm: the less light passes through, the more active the protection.

Unlike conventional sunscreens, the formula does not block visible light in its entirety. Transmittance gradually increases beyond 420 nm, allowing the wavelengths necessary for daily biological balance to pass through.

Targeted protection, without compromising on essentials.

Transmittance measurement on the 380–450 nm spectrum, performed on the fluid.

Transmittance = 1: no absorption

Transmittance = 0: total absorption

Long-lasting hydration

From the first hour, the fluid boosts skin hydration by +117%. This hydration lasts over time: +99% at 2 hours and +86% at 4 hours.

Real effectiveness, measured under instrumental conditions on untreated skin.

Instrumental test performed on the fluid, comparison vs. untreated skin.

Reduction of oxidative stress associated with pollution

Under simulated urban pollution conditions, the fluid significantly reduces the production of ROS, reactive oxygen species responsible for cutaneous oxidative stress. At 0.001%, the reduction reaches 23%.

Results obtained on human skin cells (HaCaT), which demonstrate active protection at the cellular level, where the damage from pollution truly begins.

In vitro test on human skin cells (HaCaT), comparison vs. control exposed to pollution alone.

2. The urban protective mist

BLUE LIGHT PROTECTION

Our mist filters 15% of the HEV spectrum in the highest-energy wavelengths, those that penetrate most deeply into the skin. On the curve, this translates to low transmittance starting at 380 nm: the less light that passes through, the more active the protection.

As with the fluid, the formula does not block visible light in its entirety. Transmittance gradually increases beyond 420 nm, allowing the wavelengths necessary for daily biological balance to pass through.

Targeted protection, with no compromise on the essentials.

Transmittance measurement on the 380–450 nm spectrum, performed on the mist.
Transmittance = 1: no absorption
Transmittance = 0: total absorption

REDUCTION OF OXIDATIVE STRESS RELATED TO POLLUTION

Under simulated urban pollution conditions, the mist significantly reduces the production of ROS, reactive oxygen species responsible for cutaneous oxidative stress. At 0.1%, the reduction reaches 43.4%. At 1%, it climbs to –81.8%.

Results obtained on human skin cells (HaCaT), which translate to active protection at the cellular level, where the damage from pollution truly begins.

In vitro test on human skin cells (HaCaT), comparison vs. control exposed to pollution alone.

LONG-LASTING HYDRATION

The mist maintains a high level of skin hydration over time: +47.6% after 1 hour, +44.8% after 2 hours, and +53.5% after 4 hours.
Proven efficacy, measured under instrumental conditions on untreated skin.

Instrumental test conducted on the mist, comparison vs. untreated skin.