December 31 (HealthDay News) -- Salicylic acid, the key component that gives aspirin its anti-inflammatory and pain-relieving properties, may be something humans can produce on their own, a new study suggests.

Salicylic acid (SA) previously had been found in the blood of people who had not taken aspirin recently -- especially vegetarians. This made sense because salicylic acid is a natural substance found in fruits and vegetables.

However, researchers in the United Kingdom who gave study participants benzoic acid, another natural substance in fruits and vegetables that the human body could use to produce salicylic acid, concluded that people can make their own SA based on the subsequent changes in the participants' SA levels.

Their findings appear in the Dec. 24 issue of the Journal of Agricultural and Food Chemistry.

"It is, we suspect, increasingly likely that SA is a biopharmaceutical with a central, broadly defensive role in animals as well as plants," the authors wrote in a news release issued by the journal's publisher. "This simple organic chemical is, we propose, likely to become increasingly recognized as an animal bioregulator, perhaps in a class of its own."

SOURCE: American Chemical Society, news release, Dec. 22, 2008