Quistes

A 12-week RCT in healthy Asian women found that daily almond consumption increased skin resistance to UVB-induced pigmentation and reduced photodamage markers. This constitutes the first clinical evidence that oral almond intake may provide photoprotective benefits, though the precise mechanism is not fully established.

Oral aloe vera gel powder has been studied in animal models for prevention of UVB-induced reductions in skin elasticity and extracellular matrix damage. Clinical trials show oral aloe vera and aloe sterol supplementation reverse UV-related photoaging markers. Topically, aloe vera is widely used for sunburn and UV-induced erythema with documented efficacy.

In vitro studies show bixin applied to skin cells prevents UV-induced DNA damage, and dietary tocotrienols accumulate in skin and protect against UVB-induced oxidative stress. Norbixin is under investigation as a photoprotective agent for retinal UV damage. Traditional use of annatto as a sunscreen by Amazonian indigenous peoples is well documented.

Ascorbyl palmitate reduces UV-induced free radical formation and has been shown to produce approximately 50% faster reduction in UV-induced erythema versus placebo in human subjects. However, the evidence is mixed: in vitro studies show that AP can paradoxically promote UVB-induced lipid peroxidation and cytotoxicity in keratinocytes via oxidized lipid metabolites from its palmitoyl chain. Clinical use is primarily as a complementary antioxidant additive to UV filters, not as a standalone photoprotectant.

A carotenoid antioxidant from Haematococcus pluvialis microalgae with multiple human RCTs demonstrating protection against UV-induced skin deterioration. A 16-week RCT in 65 healthy women (6 mg or 12 mg/day) showed astaxanthin prevented worsening of wrinkle parameters and skin moisture that occurred in placebo. A 2020 systematic review of 11 clinical studies found 3–6 mg/day for 4–16 weeks protected against UV-induced damage and minimized photoaging signs.

Tocopherols including the beta and delta forms absorb in the erythemal UV range and act as antioxidants that quench UV-generated reactive oxygen species in skin. Mixed alpha-beta-gamma-delta tocopherol preparations have been used in sunscreen compositions, providing both UV absorption and antioxidant protection. Delta-tocopherol applied topically or taken orally has been investigated for protection from UV radiation damage.

Beta-carotene is a provitamin A carotenoid with multiple human trials demonstrating reduced UV-induced skin erythema when taken orally. A meta-analysis showed dietary beta-carotene supplementation is efficacious in protecting skin against UVB-induced erythema. Beta-carotene at 24 mg/day from algal sources was found equivalent in erythema protection to a mix of three carotenoids.

Topical application of broccoli sprout extract reduced UV-induced erythema (skin reddening) by up to 37% compared to untreated skin in a human clinical study published in PNAS. Oral glucoraphanin has also been shown to induce cytoprotective phase II enzymes in human skin biopsies after UVB exposure.

Calendula's carotenoids, flavonoids, and phenolic constituents demonstrate measurable UV-protective and antioxidant activity in laboratory and animal models. Preclinical studies confirm reduction of UV-induced ROS generation and protection of dermal collagen. After-sun formulations with calendula are widely used in practice.

Capsanthin has been shown to protect human dermal fibroblasts against UVB-induced cytotoxicity, DNA strand breaks, and apoptosis at physiologically relevant concentrations. Its photoprotective potency is comparable to lutein in cell-based assays.

Carotenoids including beta-carotene are well-established as providing systemic photoprotection against UVB-induced erythema and have been shown to inhibit molecular markers of oxidative stress including ICAM-1, heme oxygenase-1, and matrix metalloproteinases. Beta-carotene has proven efficacy in reducing UV-induced photosensitivity in erythropoietic protoporphyria. Evidence in normal skin is positive but more modest than in photosensitive conditions.

Beta-carotene from carrots, as well as other dietary carotenoids, provides modest photoprotection by accumulating in skin and decreasing UV-induced erythema. Human interventional studies have documented reduced UV sensitivity with carotenoid-rich diets or supplements. A 2024 RCT found beta-carotene supplementation (8 mg/day, 16 weeks) significantly reduced UV-induced erythema.

Oral intake of green tea catechins reduces UV-induced erythema and skin DNA damage in human clinical studies. EGCG also protects against UVB-induced immunosuppression in mouse skin. Both oral and topical catechin administration show photoprotective effects, with oral intake reducing skin erythema more reliably.

UV radiation reduces stratum corneum ceramide levels and disrupts the skin's lipid barrier, contributing to increased TEWL, erythema, and hyperpigmentation. Clinical studies published in peer-reviewed dermatology journals show that ceramide-containing sunscreen and moisturizer regimens significantly reduce UV-induced erythema and hyperpigmentation, improve skin hydration, and preserve normal superficial skin cell morphology compared to untreated UV-exposed skin. Ceramides are thus recognized as providing additive photoprotection benefits beyond standard UV filtering.

Topical copper chlorophyllin has demonstrated clinical benefit in reversing signs of photodamaged skin, and preclinical data suggest chlorophyll pigments may act as a UV-absorbing shield. The same 8-week pilot study on photoaged skin showed improvements in solar lentigines and UV-related pigmentation. Chlorophyll's porphyrin ring absorbs in UV-visible wavelengths, providing a theoretical photoprotective mechanism.

Topical chlorophyllin complex has been clinically studied for UV-induced photodamage. A 2015 pilot study demonstrated effectiveness for mild-to-moderate photodamage and solar lentigines over 8 weeks. A 2016 biopsy study confirmed upregulation of ECM repair biomarkers (procollagen, fibrillin, hyaluronic acid) comparable to tretinoin. Evidence addresses repair of existing photodamage rather than primary UV prevention.

Cocoa flavanols showed photoprotective potential in some RCTs by improving minimal erythema dose and reducing markers of UV-induced damage, though one 12-week double-blind RCT did not demonstrate a statistically significant effect on UV sensitivity (MED). In vitro evidence strongly supports UV protection via antioxidant and anti-MMP mechanisms.

Curcumin from turmeric has documented anti-inflammatory, antioxidant, and potential photoprotective effects, including inhibition of UV-induced melanoma cell proliferation in vitro and chemopreventive activity against UV-induced skin damage. It is listed among documented photochemoprotective phytochemicals in Afaq and Mukhtar's authoritative review.

Alpha-tocopherol is a well-characterized photoprotective antioxidant in human skin, scavenging UV-generated peroxyl radicals and inhibiting lipid peroxidation and ROS accumulation in keratinocytes. Studies confirm that topical α-tocopherol can protect against UVA-induced DNA damage and cell death both pre- and post-UV exposure.

Tocopherols, including the delta form, are lipid-soluble antioxidants in skin that protect against UVA-induced lipid peroxidation, glutathione depletion, and ROS-mediated cell damage. A randomized clinical study evaluated delta-tocopherol glucoside for its ability to increase the skin antioxidant pool and reduce stratum corneum lipid peroxidation after UVA irradiation. The vitamin E class broadly provides photoprotective antioxidant defense, though most UV clinical trials specifically used α-tocopherol.

EGCG, the major catechin in green tea, has extensive evidence for skin photoprotection in preclinical and some human studies. It inhibits UV-induced leukocyte infiltration, antigen-presenting cell depletion, and oxidative stress in skin. Human studies combining green tea polyphenols showed reduced UV-induced erythema and decreased pro-inflammatory 12-LOX metabolites.

Ellagic acid from pomegranate, berries, and other sources has shown anti-inflammatory, antioxidant, and antiproliferative properties relevant to UV photoprotection. Pomegranate's ellagic acid content is identified as a key photoprotective component, and ellagic acid is a major constituent of the grape polyphenols shown in human dietary studies to reduce UV-induced pro-inflammatory gene expression.

Ferulic acid is a hydroxycinnamic acid antioxidant documented to improve the stability and photoprotective efficacy of vitamins C and E in topical formulations. Adding 0.5% ferulic acid to a vitamin C + E solution approximately doubled the antioxidant protection factor and photoprotective effect against thymine dimer formation. The 2025 PING review identified ferulic acid derivatives among photoprotective non-filtering ingredients.

Genistein protects skin against UVB-induced oxidative stress, inflammation, and wrinkling via antioxidant and anti-inflammatory mechanisms. Both dietary intake and topical application have been shown to suppress UVB-induced proinflammatory cytokines and reduce photoaging markers. Human, animal, and cell-culture data all support this relationship.

A 2010 PubMed-indexed animal study found that orally consumed 5% goji berry juice significantly reduced UV-induced inflammatory edema, protected against UV immunosuppression in a dose-dependent manner, and guarded against UVA-induced lipid peroxidation in skin. Two inducible endogenous skin antioxidants (haem oxygenase-1 and metallothionein) were mechanistically implicated.

Preclinical cell studies demonstrate that amla extract protects skin from UV-B radiation damage, is four times more protective than vitamin C in protecting skin cells from UV damage, and the Phyllanthus species has been shown to protect skin DNA from sunlight damage.

Dietary grape contains proanthocyanidins, resveratrol, and ellagic acid documented for UV photoprotection. A prospective human study found 75 g/day of California table grape powder for 14 days reduced UV-induced pro-inflammatory cytokines (including IL-22) and modified UV-associated gene expression. Resveratrol and proanthocyanidins are identified as key responsible polyphenols.

GSE's OPCs neutralize free radicals generated by UV exposure and reduce UV-induced oxidative stress to skin cells. Topical GSE application provides secondary photoprotection by dampening the ROS cascade triggered by ultraviolet radiation. This complements but does not replace sunscreen.

Green tea contains polyphenols (primarily EGCG) with established photoprotective activity. Animal studies show green tea polyphenols reduce harmful effects of UV exposure; human studies with green tea polyphenol supplementation showed reduced UV-induced erythema and inhibition of pro-inflammatory metabolites associated with sunburn. A clinical study supplement containing green tea extract alongside other antioxidants demonstrated increased minimal erythema dose over 12 weeks.

H. italicum flavonoid complexes have been shown to possess photoprotective activity against UVB-induced erythema, and UVA-induced MMP-1 expression in dermal fibroblasts is significantly suppressed by HIEO. A clinical night cream study with H. italicum extract reduced UV-induced skin spots by 13.2%.

Glutathione and its enzyme glutathione-S-transferase π (GST-π) play documented protective roles against UV-induced skin damage and melanoma pathway activation. RCTs show that the melanin-lowering effects of oral GSH are most pronounced in sun-exposed areas of the skin. GST-π present in keratinocytes and melanocytes has a protective role against sun exposure-associated melanoma progression.

LA and LA-rich vegetable oils have demonstrated photoprotective effects in preclinical models, and topical LA inhibits UV-induced hyperpigmentation and can accelerate turnover of UV-damaged keratinocytes. The 2024 MDPI review of LA in skin health includes photoprotection among confirmed biological activities of topically applied LA based on animal and skin cell models.

Lutein is a dietary carotenoid that accumulates in skin and provides photoprotection. Human studies show that lutein supplementation as part of mixed carotenoid formulations reduces UV-induced erythema and molecular markers of skin damage. In a crossover study, lutein provided complete protection against UVA/B-induced ICAM-1, HO-1, and MMP-1 gene expression when taken during the first study period.

Luteolin provides photoprotection against both UVB and UVA radiation by reducing ROS formation, suppressing DNA damage, inhibiting MMP activation, and preserving collagen in preclinical cell and animal models. It shows promise as a topical photoprotective agent.

Lycopene, a carotenoid found in tomatoes, has human clinical evidence for systemic photoprotection. A 12-week supplementation of lycopene-rich tomato nutrient complex completely inhibited UVA1- and UVA/B-induced intercellular adhesion molecule 1, heme oxygenase-1, and MMP-1 gene expression. A 2021 review confirmed lycopene-rich tomato paste protected against UV-induced molecular markers including upregulated procollagen I deposition.

A 2023 study in Molecules (PMC) tested maqui berry extracts on human skin fibroblasts exposed to UVB radiation, finding the extract had high antioxidant capacity, did not cause cytotoxicity, and protected fibroblasts from UV-induced oxidative damage. Ellagic acid in maqui may suppress UV-induced collagen-degrading enzyme activation. Evidence is currently at the in vitro stage; no human UV skin protection RCT exists.

MMSC protects keratinocytes and dermal fibroblasts from UVB-induced apoptosis and ROS generation in vitro, and topical application (5–10%) reduces UVB-induced erythema and Langerhans cell depletion in hairless rat skin in vivo. It induces collagen synthesis and reduces MMP-1 in UVB-irradiated fibroblasts, suggesting anti-photoaging activity.

Milk thistle contains silymarin, which has been documented in multiple studies to inhibit UV-induced inflammation, oxidative stress, and photocarcinogenesis. It inhibits UVB-induced COX-2 expression and prostaglandin tumor promoters in skin, and is listed among the most promising photochemoprotective botanicals in authoritative phytochemistry reviews.

EVOO's squalene, vitamin E, and polyphenols provide antioxidant protection against UV-induced oxidative damage in skin when consumed dietarily or applied topically. Squalene in EVOO specifically protects against singlet oxygen generated by UV exposure. Mediterranean populations consuming high EVOO show epidemiologically lower rates of UV-related skin damage.

PABA is an FDA-approved UV filter used topically in sunscreens since the 1940s–1950s, absorbing UVB radiation to prevent sunburn. It is listed as an active sunscreen ingredient under FDA monograph categories. Its topical use for sun protection is well-established, though it has largely been replaced in modern sunscreens due to allergy concerns.

Retinyl palmitate reduces markers of UV-induced photoaging, including collagen degradation, inflammatory cytokines, and apoptosis in skin cells. Multiple studies confirm RP's ability to partially reverse and reduce UVB-induced skin damage.

Dexpanthenol has demonstrated anti-inflammatory effects against UV-induced erythema in experimental studies. PubMed (PMID 12113650) reports it exerts anti-inflammatory effects on UV-induced erythema, and it is widely used for sunburn soothing. D-panthenol is noted in multiple references as being used to relieve sunburns.

Peach flower extract provides demonstrated photoprotection in animal models, dose-dependently inhibiting UVB-induced erythema and ear edema. The active compounds are kaempferol glycosides, particularly multiflorin B. This is one of the more robustly preclinically studied applications for peach.

Pine bark extract (primarily as Pycnogenol from Pinus pinaster) contains proanthocyanidins with documented UV photoprotective activity. Clinical evidence demonstrates it reduces UV-induced hyperpigmentation and melasma, improves skin barrier function, and provides oral photoprotection. Reviews confirm photoprotection as a primary evidence-based use of pine bark extract supplements.

Polypodium leucotomos extract (PLE), a tropical fern, is one of the most extensively studied oral photoprotective agents with multiple human clinical studies. In a clinical study of 22 subjects (Fitzpatrick I–III), oral PLE decreased UVB-induced changes in 17/22 subjects clinically and all 22 histologically. Doses up to 1200 mg/day have been used; 480 mg/day is typical for sun damage prevention.

Pomegranate is rich in ellagic acid, punicalagins, and other polyphenols documented for photoprotective effects against UV-induced skin damage. Pomegranate fruit extract is included in Afaq and Mukhtar's authoritative review of photochemoprotective botanicals and has demonstrated inhibition of UV-induced inflammation and tumor promotion in preclinical models.

Pycnogenol (French maritime pine bark extract) is a proanthocyanidin-rich extract with clinical and mechanistic evidence for UV photoprotection. A 30-day clinical trial in 30 women with melasma showed Pycnogenol (75 mg/day) significantly reduced melasma area and pigmentary intensity. A review of clinical and molecular evidence concluded Pycnogenol intake provides photoprotection, reduces hyperpigmentation, and improves skin barrier function.

Quercetin is a flavonol polyphenol with documented photoprotective effects against UV-induced skin inflammation, oxidative stress, and immunosuppression. It is included in multiple phytochemical photoprotection reviews as having chemopreventive effects against photocarcinogenesis through inhibition of UV-activated cellular signaling pathways.

Resveratrol, a stilbenoid from grape skins, suppresses UV-induced tumorigenesis and reduces inflammatory mediators (IL-6, COX-2). Topical resveratrol was shown in 1997 to prevent skin cancer development in carcinogen-treated mice. Human dietary grape studies showed resveratrol-containing polyphenols reduced UV-induced pro-inflammatory cytokines via multiple pathways.

Rosehip's antioxidants—particularly vitamin C, polyphenols, and carotenoids—protect skin from UV-induced reactive oxygen species and reduce photo-aging. A 2024 systematic review confirmed rosehip protects 'photo-aged skin' via vitamin C antioxidant mechanisms. Topical rosehip formulations with UV-protective antioxidants are documented in dermatological literature.

A placebo-controlled crossover human study found oral rosemary and grapefruit extract combination reduced UV-induced skin erythema from the first day of intake at both 100 mg and 200 mg doses. In vitro studies in human keratinocytes confirm rosemary diterpenes provide genoprotection against UVB-induced DNA damage and reduce ROS and inflammatory interleukins.

Rosmarinic acid (RA), a natural phenolic compound found in rosemary and related herbs, has demonstrated photoprotective potential when incorporated into sunscreen formulations. A 2025 PMC study showed RA enhanced both in vitro and in vivo photoprotection of UVB filters and reduced oxidative stress in the stratum corneum. It is classified as a potential non-filtering photoprotective additive.

Rutin's potent antioxidant and free-radical scavenging properties protect skin cells from UV-induced oxidative stress. In vitro, rutin scavenges ROS generated by UV exposure in human dermal fibroblasts, reducing oxidative DNA damage and skin cell senescence associated with photoaging.

Schisandrin B has been shown in vitro to protect skin from UVB-induced damage by blocking COX-2, IL-6, and IL-18 pathways and inhibiting MMP-mediated collagen degradation (PMC11984061). A 2018 MDPI study demonstrated schisandra extract protects keratinocytes from pollution/UV damage via Nrf2 and AhR pathway modulation. These mechanisms underlie photoprotective and anti-photoaging activity.

Selenium is an essential trace mineral that functions as a component of antioxidant selenoproteins (glutathione peroxidase, thioredoxin reductase), contributing to protection of skin cells against UV-induced oxidative damage. A 7-week human study using a carotenoid/antioxidant complex including organic selenium significantly increased actinic erythema threshold by 20% (p=0.01) and reduced UV-induced p53 expression, sunburn cell count, and lipid peroxidation.

Studies report that sesame oil can filter approximately 30% of UV rays, offering modest photoprotective activity. Sesame oil's antioxidant composition (vitamin E, sesamol, sesaminol) helps neutralize UV-induced free radicals in skin cells. A 2018 California State University study reported topical sesame oil may create a protective UV barrier layer. Evidence supports use as a supplemental (not primary) photoprotectant.

Shea butter contains cinnamic acid esters that absorb UV radiation (250–300 nm) and confer a natural SPF estimated at 3–6. It has been shown to increase the photostability and SPF of formulated sunscreen systems. Vitamin E and polyphenol antioxidants further mitigate UV-induced oxidative damage to skin cells.

Silymarin, from milk thistle (Silybum marianum), has documented photoprotective effects with particular evidence for inhibition of UV-induced inflammation, oxidative stress, and photocarcinogenesis. Studies show silymarin inhibits UVB-induced COX-2 expression and production of prostaglandin tumor promoters in skin. Animal studies showed inhibition of UV-induced edema, erythema, and leukocyte infiltration.

Squalene is a primary endogenous antioxidant in human skin that is depleted by UV radiation, and its oxidation products contribute to skin damage. Exogenous squalane has been shown in cell studies to counteract UVA-induced ROS production, DNA damage, apoptosis, and collagen metabolism disruption. A squalene/nanowire oleogel formulation attenuated UVB-induced skin photoaging in an animal model.

Sulforaphane is the most extensively studied dietary Nrf2 activator for UV photoprotection. Topical broccoli-sprout preparations reduced UV-induced erythema in human skin. Both topical and oral applications activate cytoprotective responses against UV-driven DNA damage, oxidative stress, and inflammation.

Vitamin E in sunflower seed oil is an established antioxidant that protects skin from UV-induced free radical damage and premature photoaging. Topical sunflower oil is recognized as providing a degree of oxidative protection against sun damage. Beta-carotene in sunflower oil also contributes photoprotective antioxidant activity.

Diet-derived and topically applied tocotrienols accumulate in skin and protect against UV light-induced oxidative stress. Studies show tocotrienols provide stronger photoprotective effects than alpha-tocopherol. Clinical research confirms oral tocotrienol intake reduces UVB-induced skin damage.

A systematic review and meta-analysis of 21 intervention trials found tomato and lycopene supplementation significantly increases the minimal erythemal dose (UV resistance), reduces skin erythema, and decreases expression of MMP-1 and ICAM-1 (UV damage markers). A randomized controlled trial showed tomato paste rich in lycopene protects against UV-induced collagen damage and mitochondrial DNA deletion in human skin.

Curcumin is documented to prevent UV-induced skin photoaging and inflammation through NF-κB inhibition, ROS scavenging, and suppression of UV-activated signaling pathways (EGFR-MAPK, NF-κB, Nrf2/ARE). A 2025 Frontiers in Pharmacology review confirmed curcumin as an anti-photoaging agent. In vitro and limited clinical data support protective effects against UV-induced oxidative damage.

A randomized placebo-controlled clinical trial found topical 1% UA cream significantly reduced UV-induced erythema by approximately 14% compared to an untreated skin area. Lower-dose UA and placebo showed no protective benefit. Mechanistically, UA reduces skin inflammatory signaling and supports immune cells in the skin against UV-driven damage.

Vitamin A and its derivatives are involved in skin cell repair and photoprotection. In combination antioxidant oral supplement studies for photoprotection, vitamin A is consistently included as a key component. A 12-week clinical study using a supplement containing vitamins A, C, D3, E, selenium, lycopene, lutein, green tea, polypodium, and grape extracts demonstrated increased MED and improved photoprotection markers in 30 subjects.

Niacin (nicotinic acid), as a precursor to NAD+, supports cellular energy metabolism and DNA repair in UV-exposed skin. Oral nicotinamide (the amide form) is the most clinically validated form for UV photoprotection, demonstrating a 23% reduction in new non-melanoma skin cancers in an RCT. Niacinamide (nicotinamide) and niacin share NAD+ precursor activity relevant to UV-induced DNA repair.

Niacinamide (nicotinamide, vitamin B3) is recognized as a leading oral photoprotective agent, with a Phase 3 randomized clinical trial demonstrating it reduced new non-melanoma skin cancers (NMSCs) by 23% in high-risk patients. It improves DNA repair and prevents UV-induced immunosuppression. It is among the top-ranked non-filtering photoprotective ingredients in a 2025 systematic review.

Vitamin C (L-ascorbic acid) is a potent antioxidant with multiple studies showing protection against UV-induced erythema, sunburn cells, and thymine dimer formation. In a double-blind placebo-controlled study (10 subjects, 8 days of 2 g/day combined with vitamin E), median MED increased significantly versus placebo. Topically, 15% L-ascorbic acid alone provided significant protection against UV-induced erythema and sunburn cell formation.

Vitamin E (tocopherol) is a lipid-soluble antioxidant protecting cell membranes from UV-induced lipid peroxidation, with human clinical data showing increased MED and reduced UV-induced erythema. Combined with vitamin C, it raised the sunburn threshold in a double-blind placebo-controlled trial. Topically, 1% alpha-tocopherol alone provides significant protection against UV-induced erythema and sunburn cell formation.

Dietary lycopene from watermelon provides measurable endogenous photoprotection by scavenging UV-induced singlet oxygen radicals in skin. Clinical trials show lycopene supplementation increases the minimum erythema dose (MED) and reduces UV-induced skin damage markers.

A 2022 review of studies cited by Healthline found that polyphenols from Yucca periculosa species have photoprotective activity and may help absorb UVB rays. These results come from animal and in vitro models, not human trials. Yucca's resveratrol content is separately associated with UV-induced DNA damage protection. The evidence is preclinical.

Zeaxanthin, a carotenoid structural isomer of lutein, has demonstrated photoprotective properties. Oral high-dose zeaxanthin has been shown to protect against sunburn, cause a skin tint resembling a tan, and allow sunburned skin to recover more healthily. It is commonly studied alongside lutein in photoprotective carotenoid combination trials.

Tartaric acid, as an AHA, is used in cosmetic products described as targeting sun-related skin damage. AHAs broadly have been studied for photoaging reversal; tartaric acid's role in chelating metal ions and inhibiting UV-induced lipid peroxidation is proposed mechanistically. However, direct human clinical trial evidence for tartaric acid specifically in reversing UV/sun damage is not established independently of the wider AHA class.

Argan oil has a long traditional use as a sun protectant among Moroccan women. A 2013 cell culture study confirmed that tocopherols and fatty acids in argan oil protected skin cells against UV-induced oxidative damage. No controlled human UV protection trials have been published.