In India, the smell of turmeric, the bright yellow spice used in curries, fills almost every restaurant and home. Indians eat turmeric because they like it, but rapidly growing evidence indicates that the spice is giving them much more than flavor.

Thousands of years ago, Ayurvedic and traditional Chinese medicine recognized turmeric as a healing agent for everything from flatulence to liver disease. Now research demonstrates that properties of this zesty spice may be useful for lowering rates of breast, prostate, lung and colon cancers, and also for treating breast cancer, inflammatory bowel disease, Crohn’s disease and possibly cystic fibrosis. But even newer and especially exciting research concerns the relationship between turmeric and Alzheimer’s disease.

Nearly 10 years ago, researchers in India became curious about the influence turmeric might have on rates of Alzheimer’s. They looked to see how many people over age 65 in a town in India had signs of the disease, versus a similar group of people in a similar-sized Pennsylvania town, where most people eat little—or no—turmeric. What they found: In India, just 4.7 per 1,000 person-years (a common measure of incidence rate) showed signs of Alzheimer’s, compared with a rate of 17.5 per 1,000 person-years in Pennsylvania. In fact, India has among the lowest rates of Alzheimer’s disease in the world. Another study, from the National University of Singapore, involved 1,010 people over age 60. Those who reported that they ate curry “often or very often” or even “occasionally” scored higher on mental performance tests than those who rarely or never consumed it.

WHAT IS TURMERIC?

Turmeric is a powder made from the root of the plant Curcuma longa, which grows in southern Asia. The part of the plant that is responsible for healing is the yellow pigment, called curcumin.

When it comes to health-giving properties, curcumin gives twice. It is a potent anti-inflammatory agent, without the potential side effects of anti-inflammatory drugs. These include damage to the lining of the stomach and intestines and a greater risk for kidney and liver problems, heart attack and stroke. Next, curcumin is a powerful antioxidant—it tracks down and reduces free radicals, insidious molecules that otherwise would cause damage in the body. Both of these properties are important when it comes to preventing or slowing the progression of Alzheimer’s disease.

In healthy people, immune cells attack and destroy amyloid-beta plaques, a buildup of proteins between neurons in the brain. But in people with Alzheimer’s, this immune response is less efficient and allows plaques to form. Plaque triggers inflammation and free radicals, both of which cause cell damage in the brain. Curcumin slows this harmful process in a number of ways—it forms a powerful bond with the amyloid protein that prevents the protein from clumping… it may break down plaques as well, preliminary research demonstrates… and finally, as I noted before, curcumin reduces the oxidative damage and brain inflammation that are linked to Alzheimer’s disease.

CHOLESTEROL BLASTER

There is yet more good news about curcumin’s power to prevent and even fight Alzheimer’s disease. Elevated cholesterol is thought to be involved in the development of Alzheimer’s—and studies demonstrate that curcumin reduces cholesterol. In one study, healthy volunteers took 500 mg of curcumin supplements every day for one week. Result: Reduced levels of total cholesterol and also lipid peroxides (markers of free radical damage to fats).

SPICE UP YOUR DIET

I encourage all my patients, especially those over age 50, to consume one or two teaspoons a day of turmeric. There are many ways to incorporate this spice into your regular diet. You can sprinkle it into egg salad or over vegetables while sautéing… add it to soups or broths… put it on fish or meat… and use it to flavor rice or a creamy vegetable dip. And of course, turmeric adds zing to curries. If you want to make the most healthful curry dishes, it is important to purchase turmeric as a separate spice—lab tests show that many curry powders in this country contain almost no turmeric.

Good brand: Great Organic Spices (www.GreatOrganicSpices.com, $3.99 for six ounces).

Those who don’t love turmeric—or those who want to get even more of its protective effects—can take curcumin in supplement form. I prescribe 2,000 mg a day for people who have a strong family history of Alzheimer’s disease or who show signs of dementia.

Good brands: New Chapter Turmericforce, which is available online (800-543-7279, www.NewChapter.com, $28 for 60 400-mg softgels) and Life Extension Super Curcumin with Bioperine (800-544-4440, www.lef.org, $26 for 60 800-mg capsules).

Anyone taking blood-thinning drugs should discuss using turmeric or curcumin supplements with a doctor, because curcumin is a natural blood thinner. Turmeric also can cause gallbladder contractions, so those with a history of gallstones or gallbladder problems also should consult a doctor. There is no risk in mixing curcumin with pharmaceutical drugs for Alzheimer’s disease.