Nordihydroguaiaretic acid (NDGA) is a potent antioxidant compound found in the long-lived creosote bush. It is believed that NDGA reduces cell damage by free radicals, so under the free-radical theory of aging, could be responsible for the bush's long life.
A 1986 study involved feeding female mosquitos NDGA to test the effect on their average life span. While the usual mosquito life span was 29 days, the NDGA-fed mosquitos lived an average of 45 days—an increase of 50 percent.
A 2008 study reported that nordihydroguaiaretic acid lengthened the lifespan of male mice, but not of female mice.
The plant has been used to treat a variety of illnesses including infertility, rheumatism, arthritis, diabetes, gallbladder and kidney stones, pain and inflammation but its use is controversial. It was widely used during the 1950s as a food preservative and to preserve natural fibers but was later banned after reports of toxicity during the early 1960s. Recently, it has been used as a nutritional supplement, however renal and hepatotoxicity are reported for chronic use of creosote bush and NDGA.