Natural treatments for sunburn

DEFINITION: Treatment of burns to the skin caused by overexposure to the sun.

PRINCIPAL PROPOSED NATURAL TREATMENTS: Epigallocatechin gallate (bioflavonoid in green tea), vitamin C, vitamin E

OTHER PROPOSED NATURAL TREATMENTS: Aloe vera, beta-carotene and other carotenoids, chocolate, coriander oil, jojoba, oligomeric proanthocyanidins, poplar bud, sage, Vitis vinifera

Introduction

Sunburn is a common, short-term skin inflammation caused by overexposure to the sun. Besides the familiar redness, pain, blistering, and flaking, overexposure to sunlight can lead to long-term skin damage, including premature aging and an increased risk of skin cancer.

The chief culprit in sunburn is not the sun’s heat but its ultraviolet radiation, which occurs in the forms UVA and UVB. This radiation acts on substances in the skin to form chemicals called free radicals. These free radicals appear to be partly responsible for the short-term damage of sunburn and perhaps for long-term damage from the sun.

Conventional approaches to sunburn focus on prevention: staying out of the sun (especially when the sun is strongest), wearing protective clothing, and using sunscreen. Sunscreen blocks much of the radiation from the skin and helps prevent inflammation. A study of 1,383 Australians suggests that regular sunscreen use may also diminish the number of tumors caused by one form of skin cancer, squamous cell carcinoma.

Many drugs and herbs may increase one’s sensitivity to the sun. Some of the drugs that increase sun sensitivity are sulfa drugs, tetracycline, phenothiazines, and piroxicam. Herbs that might increase sensitivity to the sun include St. John’s wort and dong quai. Particular care should be taken when combining any of these substances because they could amplify each other’s effects.

Principal Proposed Natural Treatments

Several studies have found that vitamin C, E, and a bioflavonoid present in green tea called epigallocatechin gallate (EGCG) may help prevent sunburn when used topically or orally. Many manufacturers already add vitamin E to sunscreens.

Vitamins C and E. Antioxidants such as vitamins C and E neutralize free radicals in the blood and in other parts of the body. Test-tube and animal studies suggest that antioxidants perform the same job in the skin. Levels of these antioxidants in skin cells decrease after exposure to ultraviolet radiation, suggesting they may be temporarily depleted.

In several animal studies, vitamins C and E applied topically to the skin helped to protect against ultraviolet damage. One study found that topical vitamin E seemed to work best against UVB, topical vitamin C protected more against UVA, and the two vitamins worked better than either one. Vitamin E was effective even when applied to mouse skin eight hours after ultraviolet exposure had occurred. Combining the vitamins with sunscreen yielded the best result, adding to the UV protection offered by sunscreen alone. In addition, preliminary evidence from a small, double-blind, placebo-controlled trial suggests that a face cream containing vitamin C could improve the appearance of sun-damaged skin.

The oral use of combined vitamins C and E may offer modest benefit. One double-blind study of ten people found that 2 grams (g) of vitamin C and 1,000 international units (IU) of vitamin E taken for eight days resulted in a modest decrease in skin reddening induced by ultraviolet light. A fifty-day, placebo-controlled study of forty people found that high doses of these vitamins in combination provided a minimal, but statistically significant, sun protection factor of about 2.13 (The sun protection factor of many sunscreens is 15 to 45.)

One study found benefits with a combination of vitamins E and C, selenium, oligomeric proanthocyanidins (OPCs), and carotenoids. However, research has not found that vitamins E and C, taken separately, are any more helpful than placebo.

Epigallocatechin gallate. Green tea contains a potent antioxidant known as epigallocatechin gallate, or EGCG. According to several studies, mice given green tea to drink or topical applications of green tea were protected against skin inflammation and carcinogenesis caused by exposure to UVB. Benefits were also seen in two preliminary human trials. The typical proposed dose of EGCG is 3 milligrams (mg) per square inch of skin.

Because of the unstable nature of EGCG, researchers explored its more chemically stable counterpart, called gallocatechin gallate (GCG), for its potential to protect the skin from ultraviolet light. Using hairless mice, researchers applied varying levels of GCG for six days while exposing the mice to ultraviolet light. The study found GCG to be highly successful at protecting the skin from sunburn, improving elasticity, and promoting collagen production.

Other Proposed Natural Treatments

Beta-carotene and mixed carotenoids. Beta-carotene belongs to a large family of natural chemicals known as carotenoids. Other members of this family include lutein, lycopene, and zeaxanthin. Widely found in plants, carotenoids are a major source of the red, orange, and yellow hues seen in many fruits and vegetables. Beta-carotene is important nutritionally because the body uses it to produce vitamin A.

Beta-carotene, alone or with lutein and other carotenoids, may be able to reduce the effects of sunburn, but study results are mixed. In a double-blind study, twenty young women took 30 mg daily of beta-carotene or placebo for ten weeks before a thirteen-day stretch of controlled sun exposure at a sea-level vacation spot. Those who had taken the beta-carotene before and during the sun exposure experienced less skin redness than those taking placebo, even when both groups used sunscreen.

A twelve-week, double-blind, placebo-controlled study found beta-carotene (at 24 mg daily) and a mixture of beta-carotene, lutein, and lycopene (at 8 mg each daily) equally protective against sun-induced skin redness. Another small double-blind trial found that a mixture of lutein and the related carotenoid zeaxanthin provided benefits when taken orally, applied topically, or, even better, taken orally and applied topically at the same time.

Two open studies of mixed carotenoids found similar results. These trials, one of twenty and one of twenty-two people, found that after taking mixed carotenoids for twelve to twenty-four weeks, participants could tolerate more ultraviolet radiation before developing skin redness. Vitamin E (500 IU per day) taken with beta-carotene in one of the studies did not significantly affect the results. Another study found benefits with tomato paste (rich in lycopene). However, because these studies were not double-blind, the results are not reliable.

Not every study has found beta-carotene or mixed carotenoids to be helpful. In a double-blind trial of sixteen older women, high doses of beta-carotene taken for twenty-three days did not provide any more protection than placebo against simulated sun exposure. Another ten-week study found that high doses of beta-carotene provided greater protection against natural sunshine than placebo, but the benefits, though statistically significant, were too minor to matter. Completely negative results were seen in a four-week uncontrolled study of high doses of mixed carotenoids.

Other natural treatments. The substances collectively called OPCs, found in pine bark and grape seed, have shown some promise for sunburn protection. Also, chocolate contains polyphenol flavonols similar to those in green tea. A special form of chocolate enriched in flavonol content might, like green tea extracts, modestly protect the skin from sun damage.

Weak evidence hints at benefit with an extract of the shoots of the Vitis vinifera plant (the common grape vine) and an extract of sage. Although research is lacking, topical jojoba, poplar bud (Populi gemma), and aloe vera are sometimes recommended for soothing sunburn pain and itch. However, one small study found that applying aloe vera gel after UVB exposure had no effect on skin redness. In a preliminary double-blind study, coriander oil applied topically was more effective than a placebo cream at reducing redness caused by UVB exposure.

Moisturizers containing aloe vera or soy can help alleviate sunburn by keeping the skin moist, which can provide a cooling effect. Aloe and soy also have antioxidant compounds that may help the healing process. Calamine may also offer benefits, and soybean oils may promote anti-inflammatory effects on the skin. A cool bath or shower can reduce discomfort, or a soak with several tablespoons of baking soda or a cup of oatmeal may provide desired relief. Some sources advise adding vinegar to the bath to speed healing, but this is highly contested. Cooled chamomile tea may offer some relief, but this, too, is not backed by science. Applying a 1 percent hydrocortisone cream can improve symptoms if the skin becomes too itchy.

Substances to avoid include ointments and petroleum jelly, which may trap heat in the skin. Products containing alcohol are not recommended. Should blisters result from exposure to sunlight, these should be left alone and not popped. If blisters cover most of the body or if chills occur with the sunburn, medical attention may be necessary.

Bibliography

Cornacchione, S., et al. “In Vivo Skin Antioxidant Effect of a New Combination Based on a Specific Vitis Vinifera Shoot Extract and a Biotechnological Extract.” Journal of Drugs in Dermatology, vol. 6, 2007, pp. 8-13.

Elmets, C. A., et al. “Cutaneous Photoprotection from Ultraviolet Injury by Green Tea Polyphenols.” Journal of the American Academy of Dermatology, vol. 44, 2001, pp. 425-32.

Greul, A. K., et al. “Photoprotection of UV-Irradiated Human Skin: An Antioxidative Combination of Vitamins E and C, Carotenoids, Selenium, and Proanthocyanidins.” Skin Pharmacology and Applied Skin Physiology, vol. 15, 2002, pp. 307-15.

Heinrich, U., et al. “Supplementation with Beta-Carotene or a Similar Amount of Mixed Carotenoids Protects Humans from UV-Induced Erythema.” Journal of Nutrition, vol. 133, 2003, pp. 98-101.

---. “Long-Term Ingestion of High Flavanol Cocoa Provides Photoprotection against UV-Induced Erythema and Improves Skin Condition in Women.” Journal of Nutrition, vol. 136, 2006, pp. 1565-69.

Helton, Brooke. "Eight Home Remedies for Sunburn Recommended By Dermatologists.” Forbes Health, 23 May 2023, www.forbes.com/health/body/home-remedies-for-sunburn. Accessed 5 Sept. 2023.

Katiyar, S. K., et al. “Green Tea and Skin.” Archives of Dermatology, vol. 136, 2000, pp. 989-94.

MacMillan, Carrie. "How to Treat a Sunburn." Yale Medicine, 7 Sept. 2023, www.yalemedicine.org/news/how-to-treat-a-sunburn. Accessed 20 Sept. 2024.

Palombo, P., et al. “Beneficial Long-Term Effects of Combined Oral/Topical Antioxidant Treatment with the Carotenoids Lutein and Zeaxanthin on Human Skin.” Skin Pharmacology and Physiology, vol. 20, 2007, pp. 199-210.

Reuter, J., et al. “Anti-inflammatory Potential of a Lipolotion Containing Coriander Oil in the Ultraviolet Erythema Test.” Journal of the German Society of Dermatology, vol. 10, 2008, pp. 847-51.

"Seven Sunburn Relief Tips (and How To Prevent It Next Time).” Cleveland Clinic, 9 Aug. 2023, health.clevelandclinic.org/sunburn-relief. Accessed 5 Sept. 2023.

Sheng, Yue-Yue, et al. “Protective Effects of Gallocatechin Gallate against Ultraviolet B Induced Skin Damages in Hairless Mice.” Scientific Reports, vol. 12, no. 1, Jan. 2022, p. 1310, doi:10.1038/s41598-022-05305-9.

Stahl, W., et al. “Dietary Tomato Paste Protects against Ultraviolet Light-Induced Erythema in Humans.” Journal of Nutrition, vol. 131, 2001, pp. 1449-51.

"Sunburn.” Mayo Clinic, 7 June 2024, www.mayoclinic.org/diseases-conditions/sunburn/diagnosis-treatment/drc-20355928. Accessed 20 Sept. 2024.