No matter how seriously you consider the risk of skin cancer or how religiously you apply sunscreen, you're likely to experience sunburn at some point. Spreading an aloe-enhanced after-sun skin-soother lotion on the burned area feels good, and unless you're allergic it's probably not going to hurt. But the chemical effects of aloe on sunburn are far from proven.
Sunburn
The University of Michigan Healthwise Knowledgebase defines sunburn as "damage to the skin resulting from excessive exposure to the sun's ultraviolet rays." Length of exposure necessary to cause damage varies between a few minutes and several hours. The characteristic redness and pain don't fully manifest until some hours after exposure.
Aloe
Aloe vera is one of several species of aloe. The plant grows long, fleshy, serrated leaves which, when broken open, ooze a juice or "gel" that's often recommended for treating minor cuts and burns. The aloe gel primarily consists of polysaccharides and water. According to a report published in the International Journal of Pharma Sciences and Research, the chemical compound acemannan, a major carbohydrate fraction of the gel, "may be related to the reported wound healing, antiviral and immune-stimulating activities of aloe."
Commercial Use
The U.S. Food and Drug Administration has approved aloe gel as a cosmetic ingredient. Many commercially available suntan lotions and sunburn treatments include aloe in their manufacture.
Course of Treatment
The University of Maryland Medical Center suggests topical use of aloe vera cream or gel to soothe a sunburn and help it heal. Apply it directly to the affected area three to four times daily as needed.
Clinical Studies
Though aloe is traditionally recommended for sunburn, according to the University of Michigan Healthwise Knowledgebase, only one human study specifically involving sunburn has been published. This study showed that "applying aloe gel after ultraviolet exposure had no effect on reddening of the skin." A large placebo-controlled trial did not find aloe effective in treating minor burns, though a small clinical trial found aloe more effective than petroleum jelly in that respect.
For Minor Burns Only
Aloe vera is only recommended for minor or first-degree sunburns, those that affect only the epidermis or outer layer of the skin. If you see oozing blisters, you probably have a second-degree burn. Do not use aloe or other herbs, but seek emergency medical help.
