New evidence suggests a common Indian cooking spice is a potent antioxidant that can prevent many diseases. The spice, turmeric, a key ingredient of curry, has been used medicinally for hundreds of years. But scientists are starting to systematically explore the sweeping qualities of the bright-yellow powder. An increasing body of scholarly research indicates that curcumin, the active ingredient in turmeric, could be used to prevent a range of illnesses, from cancer to skin disorders. Faced with a number of promising laboratory studies and animal trials, scientists are rushing to test curcumin's effectiveness in humans. The U.S. National Institutes of Health has four clinical trials registered that are recruiting patients to test curcumin for pancreatic cancer, multiple myeloma, Alzheimer's and colorectal cancer. <TABLE cellSpacing=1 cellPadding=0 width=173 align=left border=0><TD class=illustration> Research suggests that turmeric, an Indian spice, can help prevent disease. <TD width=12 rowSpan=2> Curcumin is cheap, widely available and has no known toxicities. Studies have shown that it has anti-inflammatory and cholesterol-lowering properties. And it is a potential Cox-2 inhibitor, the same mechanism targeted by Merck & Co.'s Vioxx painkiller and a promising anticancer sign. Interest in curcumin was piqued after scientists realized that people living in India had lower rates of certain cancers. Researchers theorized that eating curry, which is liberally spiced with turmeric, could be the explanation. Curcumin isn't related to cumin, a spice commonly associated with Moroccan cooking. In India, tradition calls for a bride to cover herself with turmeric to prevent wrinkles; some mothers will mix the powder with milk to ease an upset stomach. Johnson & Johnson sells a turmeric Band-Aid in India because the powder is reputed to help heal wounds.