Tanosa, an extract from the bark of the Pau d’Arco tree is being promoted in cosmetics to suppress inflammation. The bark, itself, is very interesting. Found in the rainforests of Central and South America, its common names include lapacho, taheebo and trumpet tree. The inner bark of pau d’arco is used by native tribes to treat cancer, lupus, infectious diseases, wounds, backache, toothache and sexually transmitted diseases. Pau d’arco is available in health food stores as capsules, tablets, alcohol solutions, dried bark and tea. However, pau d’arco must be boiled for at least eight minutes to release the active ingredients, making a tea from the bark ineffective unless properly prepared.
How is pau d’arco thought to treat cancer? Researchers at Moores University of California San Diego Cancer Center, the medicinal value of pau d’arco is thought to reside in certain compounds, called naphthaquinones, in the inner bark. Proponents claim that naphthaquinones enhance the immune system, cleanse the body and stimulate the production of red blood cells, which can increase the amount of oxygen the blood can carry contributing to healing.
What has been proven about the benefit of pau d’arco for cosmetics? Naphthaquinones, the active ingredients in pau d’arco bark, have shown potent antifungal properties in laboratory tests. These same compounds also have anticancer properties. Pau d’arco has killed lung cancer cells grown in the laboratory and reduced the rate of lung tumor growth in mice. Unfortunately, it must be taken in very toxic doses for any effects to occur. Because of the toxic effects, the National Cancer Institute did not seek approval to use pau d’arco as an anticancer drug and research has, for the most part, ceased. The American Cancer Society urges patients to avoid pau d’arco as an alternative treatment for cancer until more evidence is available.
What is the potential risk or harm of pau d’arco? The whole bark has no known side effects. The unrefined bark is much safer than taking extracts of the active ingredients. High doses of naphthaquinones can cause uncontrolled bleeding, nausea and vomiting.
How much does pau d’arco cost? Costs will vary depending on the health food store or the cosmetic outlet where it is purchased.
Pueraria mirifica is another natural substance being promoted in cosmetics. It comes from the White Kwao Krua herb (also known as Kwao Krua or Butea Superba) found in Thailand and Myanmar.
Its tuber contains phytoestrogens ( estrogen-like substances made by some plants) such as miroestrol, deoxymiroestrol, and coumestans, and has been used in breast enhancement supplements such as Mirifem and St. Herb. Miroestrol and deoxymiroestrol contain stronger phytoestrogens than soy or red clover, and are under investigation for possible use in hormone replacement therapy. Now in skin creams, pueraria mirifica reportedly promotes “healthy, vibrant skin” and helps to bring the body into natural balance when estrogen deficiencies are present.”
Because cosmetics and health food products are not regulated for quality and purity, the amount of pau d’arco or pueraria mirifica in different products may vary. Some may only contain trace amounts of the active ingredients.