You used SPF 50 all summer, didn’t get sunburned, applied sunscreen regularly — and then in the fall noticed that your pigment spots had become darker. The cream itself may well have worked exactly as it should. It’s just that the SPF number does not show how effectively a product covers all ranges of sunlight that can affect pigmentation. For skin with melasma, post-inflammatory hyperpigmentation, or a tendency to darken quickly, not only UVB rays matter, which is what the SPF value primarily reflects. Pigmentation is also influenced by UVA, especially its long-wave part UVA1, as well as part of visible light. That is why two products with the same SPF 50 can behave differently on this kind of skin.
SPF 50 works, but it does not describe the full scope of photoprotection
SPF — Sun Protection Factor — is determined by how much a sunscreen reduces erythema, that is, skin redness after UV exposure. This indicator is most closely associated with protection against UVB. The SPF number alone does not show how well a specific product will prevent pigmentation. UVA protection is assessed separately: in the European Union, it is recommended that the UVA protection factor be at least one-third of the declared SPF, and that the critical wavelength be at least 370 nm.
What are UVA1 and visible light
Fig. UVB, UVA1, and visible light differ in wavelength, ability to pass through glass, and depth of impact on the skin.
Solar radiation that reaches the skin consists of different ranges. In photobiology, UVB is usually considered to be approximately 290–320 nm, UVA2 320–340 nm, UVA1 340–400 nm, and visible light 400–700 nm. The boundaries may vary slightly depending on the classification, but for understanding photoprotection, the sequence itself is what matters: after UVB and UVA comes the part of the solar spectrum that is already visible to the human eye. Visible light makes up about half of the electromagnetic radiation that reaches the Earth’s surface.
UVA1 is not a separate light source, but the long-wave portion of solar UVA. In recent years, particular attention has been paid to the 370–400 nm range, which lies directly next to the boundary with visible light. Long-wave UVA1 penetrates deeper into the skin than UVB and, together with visible light, can contribute to persistent skin darkening. The main everyday source of UVA1 is the sun; a significant part of UVA also passes through ordinary window glass, unlike most UVB. Artificial UVA sources also exist — for example, in tanning beds or phototherapy — but in the context of daily photoprotection, solar radiation remains the main concern.
We receive visible light both from the sun and from artificial lighting, LED lamps, monitors, and smartphones. This also includes the blue, or high-energy visible, part of the spectrum at approximately 400–490 nm. But in melasma and sun-induced pigmentation, it is specifically solar visible light that matters most: the radiation intensity from ordinary screens in real life is much lower.
| Range | Main source in everyday life | What provides photoprotection |
|---|---|---|
| UVB, approximately 290–320 nm | Sun; most of it is blocked by ordinary window glass | UVB and broad-spectrum filters. Examples include Ethylhexyl Triazone, Octisalate, Octinoxate, Octocrylene; UVB is also covered by zinc oxide, titanium dioxide, and broad-spectrum organic filters |
| UVA2, approximately 320–340 nm | Sun | UVA and broad-spectrum filters: Avobenzone, Diethylamino Hydroxybenzoyl Hexyl Benzoate, Bemotrizinol, Bisoctrizole, zinc oxide, and others — depending on the formula and market |
| UVA1, 340–400 nm | Sun; a significant part passes through ordinary glass | Avobenzone, Diethylamino Hydroxybenzoyl Hexyl Benzoate, Bemotrizinol, Bisoctrizole, zinc oxide, and other UVA filters. For the longest UVA1 wavelengths of 370–400 nm, the spectral efficiency of formulas is especially important; MCE (Methoxypropylamino Cyclohexenylidene Ethoxyethylcyanoacetate, Mexoryl 400) was specifically developed to extend protection into this range |
| Visible light, 400–700 nm | Primarily the sun; also artificial lighting and screens | Pigments capable of absorbing or scattering visible light, above all iron oxides CI 77491, CI 77492, CI 77499, and pigmentary titanium dioxide; this is why tinted formulas are of particular interest in melasma |
This table does not mean that a sunscreen’s protection can be determined precisely just by reading the INCI list. One filter may cover several ranges, and the final spectral profile depends on concentration, the combination of filters, their photostability, and the entire formula. For the longest UVA1 wavelengths, the difference between products may be especially noticeable; modern developments are specifically aimed at extending absorption closer to 400 nm. For visible light, the situation is even more complex: conventional UV filters do not provide the same level of protection that pigmented formulas can offer.
Antioxidants and other supporting components may influence certain biological consequences of photoexposure, but this is a different mechanism. Vitamin C, vitamin E, niacinamide, or plant antioxidants do not replace UV filters or pigments that reduce the amount of radiation reaching the skin.
In real life, simpler factors are added to spectral characteristics: how much sunscreen is applied, whether it has rubbed off during the day, how much time a person spends in direct sun, and what level of UVA protection the specific formula provides. SPF 50 on the packaging is an important characteristic, but it does not describe everything that happens to the skin in the sun.
What new research has shown about UVA1, visible light, and melasma
The effect of visible light on pigmentation was demonstrated in early experimental studies in humans. UVA1 and visible light can cause long-lasting skin darkening, especially in medium and darker phototypes. Subsequent studies clarified that the contribution comes not only from UVA1, but also from the blue and part of the green region of the visible spectrum.
Particularly interesting is a 2025 randomized study involving 42 women with melasma. Over five summer months in southern France, they used one of two sunscreens with almost identical UV protection: SPF 65 and UVA-PF 35 for the tinted one, and SPF 64 and UVA-PF 36 for the untinted one. The tinted formula additionally contained pigments capable of reducing the penetration of part of visible light. Melasma did not worsen over the summer in either group, and the mean mMASI score even decreased. On this clinical scale, there was no significant difference between the products. At the same time, colorimetric measurements after five months showed better color equalization between melasma areas and the surrounding skin in the tinted sunscreen group. Despite the nearly identical SPF and UVA-PF, the pigmentation-related results were not completely the same.
At the beginning of 2026, a pilot study exposed melasma directly to visible light. Melasma areas darkened more strongly than adjacent skin, and pigmentation could intensify both immediately after exposure and later on. This same line of evidence was reinforced by the international consensus on photoprotection against visible light, published in 2026. Experts recognized visible light as a clinically significant factor in melasma and post-inflammatory hyperpigmentation. At the same time, there is still no equivalent of SPF for it — no single standardized indicator by which two products on the shelf could be easily compared.
Tinted SPF and iron oxides: why the color of the cream still guarantees nothing
For melasma and a tendency toward hyperpigmentation, tinted sunscreens with iron oxides are often recommended. Pigments really can absorb and scatter part of visible light, whereas transparent UV filters work mainly in the ultraviolet range. But the shade itself still says nothing about the level of such protection. This is clearly shown in a series of 2025 studies: in nine randomized trials involving 188 people with phototypes III–V, 30 products were tested. Twenty-four of them statistically significantly reduced visible light-induced pigmentation, but the effectiveness varied noticeably. The level of protection correlated with the amount of pigments in the formula, although the mere presence of color did not allow the result to be predicted.
The problem is also clearly visible at the labeling level. In an analysis of commercial tinted sunscreens published in 2026, the authors examined 37 products and separately contacted manufacturers regarding iron oxide content. There turned out to be very little data by which a buyer could meaningfully compare visible light protection. SPF is easy to compare by number, whereas protection against visible light today often has to be judged only by indirect signs.
The word “mineral” itself does not solve the issue either. Modern sunscreens with zinc oxide or titanium dioxide are often designed to be as inconspicuous on the skin as possible. They may work well in the UV range, but protection against visible light depends on pigments and the properties of the entire finished formula. In studies, even different tinted mineral products provided unequal protection against the combination of UVA1 and visible light.
Another confusion arises around the term “visible light” itself. In studies of melasma and photoprotection, this refers primarily to solar visible light, not the screen of a smartphone or laptop. We discuss the impact of digital screens separately in the article on the skin exposome.
What to check in your photoprotection routine if spots are getting darker
High UVB/UVA protection remains the foundation of photoprotection. Moreover, in the 2025 study, even an untinted sunscreen with good UVA protection helped prevent summertime worsening of melasma. If spots are still getting darker, it is worth checking a few things first:
- whether the sunscreen is being applied in a sufficient amount;
- whether it is being reapplied after swimming, heavy sweating, or rubbing off;
- what level of UVA protection the specific formula provides;
- how much time the skin spends in direct sun and whether shade, a hat, or other physical protection is also being used;
- if there is melasma or persistent post-inflammatory hyperpigmentation — whether the formula is designed to protect not only against UV, but also against visible light.
How much sunscreen counts as “enough”
The declared SPF is determined in the laboratory when applying 2 mg of product per 1 cm² of skin. If the layer is significantly thinner, the actual level of protection decreases. In everyday life, no one weighs cream for each area of the face, so a practical guideline is the amount that covers the length of the index and middle fingers. The neck, ears, hairline, and other exposed areas need to be covered separately. Outdoors, sunscreen should be reapplied approximately every two hours, as well as after swimming or heavy sweating.
For tinted products, the amount is especially important. If the shade is too dark, too light, or too orange, or if the formula itself feels too dense, it is easy to start applying it almost like foundation — in a thin cosmetic layer. In that case, even a well-designed photoprotective formula will not perform in real life as it did in testing. That is why a suitable shade and comfortable texture for tinted SPF are not just a matter of makeup, but also a condition for proper application.
What you can tell from the packaging
| What we see on the product | What it actually suggests | What cannot be determined from it |
|---|---|---|
| SPF 50 / 50+ | A high level of protection against erythema, primarily associated with UVB | How well the product protects against visible light |
| UVA labeling, UVA-PF | Provides information about UVA protection | Is not an indicator of protection against visible light |
| Tinted | The formula contains pigments that may potentially also work in the visible spectrum | How strong this protection is |
| Iron oxides: CI 77491, CI 77492, CI 77499 | The composition contains iron oxides capable of weakening part of visible light | Their concentration, ratio, and the effectiveness of the finished formula |
| Claim of protection against visible light / HEV | Useful additional information, especially if the manufacturer describes testing | Does not yet allow products to be compared on a single universal scale |
For SPF there is a familiar number, for UVA there are separate labeling systems, but for visible light there is still no generally accepted consumer indicator. That is why, in this area, the label gives much less information than one might wish.
Is it necessary to choose a mineral SPF
No. For skin with pigmentation, what matters is broad UV protection and, when relevant, the ability of the finished product to work in the visible spectrum. The division into “mineral” and “chemical” filters does not show this by itself. An untinted mineral SPF may protect well against UV while still allowing a significant portion of visible light to pass through, whereas a pigmented formula with iron oxides can broaden the protection spectrum.
What if you apply a regular SPF and foundation on top
A decorative product with pigments may additionally weaken part of visible light. But ordinary foundation cannot automatically be equated with a sunscreen tested for protection against visible light: the pigment concentration, spectral properties, and the amount of product on the skin are usually unknown. Therefore, the combination of “full sunscreen + foundation” may well make practical sense, but the basic UV protection should come from the sunscreen itself. Makeup is better viewed here as a possible additional layer, not as a way to compensate for an insufficient amount of SPF.
Does everyone need a tinted SPF
The most convincing data at present concern melasma, post-inflammatory hyperpigmentation, and skin that pigments markedly under the influence of visible light, especially medium and darker phototypes. For a person with fair skin and a few solar lentigines, there is no basis to automatically consider any tinted sunscreen clinically superior to a high-quality untinted product with high SPF and good UVA protection.
If spots have already appeared, do not immediately label them as “sun pigmentation” and try to erase them with acids or lasers. Melasma, solar lentigines, and post-inflammatory hyperpigmentation can look similar, but they arise for different reasons and require different strategies. We discuss separately how a fresh tan, phototype, and sun exposure affect the choice of procedures in the article on cosmetic procedures in summer.
SPF 50 may work perfectly well even if spots became more noticeable by the end of summer. For skin prone to melasma and hyperpigmentation, what matters is the broader context of photoprotection — and it does not fit into a single number on the packaging.
Sources
- International Organization for Standardization. ISO 24444:2019. Cosmetics — Sun protection test methods — In vivo determination of the sun protection factor (SPF). Geneva: ISO; 2019.
- European Commission. Commission Recommendation of 22 September 2006 on the efficacy of sunscreen products and the claims made relating thereto (2006/647/EC). Off J Eur Union. 2006;L265:39–43.
- Polena H, et al. Comparison of Visible Light-Protective Tinted Sunscreen to Untinted Sunscreen to Protect Melasma Patients During Summer. J Cosmet Dermatol. 2025;24(10):e70450.
- Renoux P, et al. Visible Light-Induced Pigmentation: Improved In Vivo Methodology for Measuring Efficacy of 30 Products in 9 Randomised Controlled Trials and Correlation With In Vitro Assessment. Exp Dermatol. 2025;34(9):e70167.
- Mann T, et al. Visible light induces skin darkening in vivo: comparative pilot studies reveal enhanced susceptibility in melasma. Photochem Photobiol Sci. 2026;25(2):299–306.
- International modified Delphi consensus statement on visible light photoprotection: effects, measurement, and recommendations. J Invest Dermatol. 2026;146(8):2094–2104.e2.
- Mohammed H, Kohli I, Lim HW. From Ultraviolet to Visible Light: Emerging Concepts in Comprehensive Photoprotection. Photodermatol Photoimmunol Photomed. 2026.
- Ruvolo E, et al. Enhancing Photoprotection: Assessing Visible Light Photoprotection in Tinted Inorganic Sunscreens. Photodermatol Photoimmunol Photomed. 2026;42(4):e70104.
- Iron Oxides in Tinted Sunscreen for Hyperpigmentation: A Product Analysis and Literature Review. 2026.
- Impact of Iron-Oxide Containing Formulations Against Visible Light-Induced Skin Pigmentation in Skin of Color Individuals. J Drugs Dermatol. 2020.
- American Academy of Dermatology. How to apply sunscreen. Schaumburg, IL: American Academy of Dermatology; 2025.
- Bimczok R, Gers-Barlag H, Mundt C, Klette E, Bielfeldt S, Rudolph T, et al. Influence of applied quantity of sunscreen products on the sun protection factor. Skin Pharmacol Physiol. 2007;20(1):57–64.
