Peppermint oil to help irritable bowel syndrome. Chile pepper seed rub to ease aching joints. Lavender to aid sleep. Hibiscus-flower tea to lower blood pressure.Once dismissed by medical experts as grandma's superstition and folklore, herbal and natural cures such as these are getting a double dose of respect by mainstream physicians. Not only are they being recommended with increasing frequency, modern researchers are doing studies that find that many of these cures do in fact possess active biological agents that do just what Grandma told you they would.MICHAEL HOGUE/Staff ArtistOne of the latest signs of how seriously such treatments are being...