Researchers are investigating whether certain supplements can reduce the skin’s response to ultraviolet radiation. Clinical studies show effects on sunburn-related redness, but preventing DNA damage and skin cancer is a separate challenge.
Could protection from the sun eventually come in a pill? The possibility has attracted researchers studying vitamin B3, tropical fern extracts, carotenoids and other compounds that affect the skin’s response to ultraviolet (UV) radiation. Some findings are encouraging, but a critical distinction is emerging: preventing visible redness is not the same as preventing molecular injury.
A 2026 randomized trial published in Photochemical & Photobiological Sciences found that oral nicotinamide and a supplement containing Polypodium leucotomos extract each increased the amount of UVA radiation required to produce visible skin redness. Neither treatment significantly lowered the specific UV-related DNA damage marker measured by the researchers. The findings reinforce why oral supplements have not been established as replacements for conventional sunscreen.
What the 2026 trial actually found
Researchers in Denmark examined 50 healthy volunteers with Fitzpatrick skin phototypes I–III. Half received 2,000 milligrams of nicotinamide each day and half received 480 milligrams daily of a commercial Polypodium leucotomos-based supplement, over 30 days. Participants underwent controlled UVA exposure before and after taking the products.
Both groups experienced approximately a 26% increase in the minimum UVA dose needed to produce visible redness, a response described as erythema. However, the researchers found no significant reduction in thymidine dimers—DNA lesions associated with ultraviolet exposure—in either skin biopsies or urine. The trial was relatively small, included only lighter phototypes, tested particular products and doses, and did not assess long-term skin cancer outcomes. Those limitations mean its redness results cannot be interpreted as evidence of clinical cancer prevention.
Why less redness is not the same as less damage
UVA penetrates the skin and contributes to oxidative stress, photoaging and DNA damage. UVB contributes strongly to sunburn and can directly damage DNA. Both types contribute to the risk of skin cancer. Redness represents a visible inflammatory response; DNA injury can occur even without an obvious burn.
Researchers therefore distinguish changes to an observable reaction, such as erythema, from prevention of molecular injury or disease. A supplement may change the threshold at which redness appears without demonstrably preventing the cellular harm that can accumulate with UV exposure.
A separate 2025 study found a similar limitation
A 2025 study involving 47 participants examined responses to narrowband UVB after supplementation with nicotinamide or Polypodium leucotomos. The fern-extract group showed about a 29% increase in the UVB dose needed for visible redness; nicotinamide did not produce a statistically significant increase in that measure. Neither treatment significantly lowered the DNA damage marker assessed. Because this research was not randomized and used narrowband UVB rather than natural sunlight, it cannot predict the products’ performance in everyday outdoor conditions.
Vitamin B3 and the stronger—but selective—skin cancer evidence
A major 2015 trial in The New England Journal of Medicine examined 386 adults who had developed at least two nonmelanoma skin cancers in the previous five years. Those assigned 500 milligrams of nicotinamide twice daily experienced 23% fewer new nonmelanoma skin cancers during one year of treatment than those receiving a placebo. The benefit was not sustained after treatment stopped.
That finding was for a particularly high-risk population, not a recommendation for healthy adults to take high-dose vitamin B3. A 2023 trial among 158 organ-transplant recipients did not show a statistically significant reduction in new keratinocyte cancers; that trial ended early because of slow recruitment. These mixed findings underscore the need for individualized clinical advice and better trials.
What researchers know about tropical fern extracts and antioxidants
Polypodium leucotomos is a fern native to the Americas. Its extracts have been investigated for possible antioxidant, anti-inflammatory and photoprotective properties. A 2025 systematic review of 47 human studies found comparatively promising results for the fern extract, carotenoids and polyphenols, but emphasized that many studies involved small samples or short treatment periods.
An October 23, 2026, narrative review of 36 eligible studies found more consistent evidence that fern extracts reduced redness or some oxidative-stress measures than that they prevented UV-induced DNA damage, especially under UVA exposure. The authors called for more standardized and clinically meaningful research. Commercial products are also not interchangeable: formulas, active ingredients and doses differ.
Supplement safety deserves the same scrutiny as effectiveness
A nutritional compound is not necessarily harmless at high doses. Supplements can produce unwanted effects, interact with medicines or be inappropriate in certain conditions. The National Cancer Institute notes that high-dose beta-carotene supplementation increased lung cancer risk in certain groups of smokers in major trials. That finding does not imply that eating carotenoid-rich foods has the same risk; concentrated supplements and ordinary diets must be evaluated differently.
The dosages tested in nicotinamide research should not be treated as self-medication instructions. Anyone considering high-dose vitamin B3 or other oral photoprotective products should first consult a qualified healthcare professional.
What the FDA and dermatologists recommend instead
The U.S. Food and Drug Administration has warned against unsupported claims that dietary supplements can substitute for sunscreen. Supplements generally do not have to demonstrate effectiveness to the FDA before being marketed, while conventional sunscreen products are regulated as over-the-counter drugs. See the agency’s consumer sunscreen guidance.
The American Academy of Dermatology recommends broad-spectrum, water-resistant sunscreen with SPF 30 or higher, applied generously and generally reapplied about every two hours outdoors and after swimming or sweating as directed. Shade, protective clothing, hats and sunglasses provide additional safeguards. These measures remain important even if a person is taking a supplement being investigated for photoprotection.
Sunburn remains common in the United States
According to a CDC report published May 21, 2026, 88.1 million American adults—an estimated 35.1%—reported at least one sunburn in the preceding 12 months in the 2024 National Health Interview Survey. Some 18.8 million reported four or more burns. Among those reporting sunburn, 55.1% said they had used sunscreen during their most recent burn.
The survey did not establish whether products had been applied in sufficient amounts or reapplied appropriately. The findings highlight the need for accurate sun-safety education—not a conclusion that sunscreen itself does not work.
Research must include people of every skin tone
The 2026 UVA trial included people with Fitzpatrick phototypes I–III. It therefore left important questions about outcomes in darker skin tones. More melanin provides some natural protection against UV radiation but does not eliminate skin cancer, photoaging or pigmentation concerns. As the American Academy of Dermatology explains, skin cancer can occur in people with every skin tone.
Future studies should include more diverse populations and outcomes such as pigmentation changes, clinical lesions and confirmed cancer rates—not simply visible redness, which can be harder to evaluate consistently across skin tones.
CDC video: How to use sunscreen
The following official video, “Sun Safety Tip: Use Sunscreen”, features CDC behavioral scientist Dawn Holman explaining sunscreen’s place in an effective sun-safety strategy. It is public-health advice, not footage from the supplement experiments.
What comes next
The oral-photoprotection field is scientifically credible and worth following. Researchers are exploring how compounds affect inflammation, oxidative stress and cellular responses to UV exposure, and whether they might reduce cancer risk for selected groups. But the next studies need larger and more diverse human samples, standardized testing and clinical outcomes rather than only laboratory or redness measures.
For now, certain oral supplements may change how the skin responds to UV light, but none has been demonstrated to replace sunscreen. A capsule that appears to reduce redness should not be treated as permission to increase unprotected sun exposure.
Research and public-health sources
- Faisal A. et al. (2026), UVA-induced thymidine dimers and erythema with nicotinamide and fern extract. Study.
- Faisal A. et al. (2025), UVB-induced DNA damage and erythema with oral supplementation. Study.
- Faisal A. et al. (2026), Narrative review of nicotinamide and Polypodium leucotomos. Review.
- Natarelli N. et al. (2025), Oral Supplements and Photoprotection: A Systematic Review. Review.
- Chen A.C. et al. (2015), Phase 3 nicotinamide skin-cancer prevention trial. Trial.
- Allen N.C. et al. (2023), Nicotinamide among transplant recipients. Trial.
- Centers for Disease Control and Prevention (2026), Prevalence and Context of Sunburn Among U.S. Adults. Report.
- U.S. FDA, Sunscreen: How to Help Protect Your Skin from the Sun.
- American Academy of Dermatology, Sunscreen guidance.
- Original reporting context: The Epoch Times; conclusions above are grounded in cited research.
Medical information is intended for public education and is not individual medical advice.
