There is no cure for Alzheimer's disease or a specific food that is recommended to ward off Alzheimer's disease, as of the time of publication. However, an ingredient in turmeric has shown promising results in helping scientists understand the disease better and may one day lead to new treatments. Turmeric is generally safely consumed by most people, but it may cause some side effects if you have certain medical conditions. If you want to know more about your risk for Alzheimer's disease and ways you can potentially prevent it, talk with your health care provider.
Turmeric Facts
Turmeric is a plant closely related to ginger, which has been grown and used extensively in India for 2,500 years. Known for its bitter taste and golden color, it's also common to other parts of Southern Asia. Researchers publishing in the "Annals of Indian Academy of Neurology" wrote that it probably started a hybrid of plants native to India, Sri Lanka and the Eastern Himalayas. Turmeric was first cultivated for its ability to dye and for use in cosmetics, then later as a cooking aid because of its aromatic properties. However, for many years systems of medicine, such as the Ayurvedic, Siddha, Unani and traditional Chinese, have used turmeric for its antiseptic, pain-relieving and detoxifying properties.
Curcumin
The reason turmeric is of interest to Alzheimer's research is because it contains a substance known as curcumin. Besides being used in curries and other spicy dishes around the world, curcumin's antioxidant and anti-inflammatory actions can improve the cognitive functioning in patients with Alzheimer's disease. At least four U.S. clinical trials were under way or recently completed in 2011 regarding the application of curcumin to Alzheimer's. The authors of the "Annals" article say a growing body of evidence has suggested many ways curcumin might help patients. For example, it may decrease the beta-amyloid plaques --- the clumpy deposits of protein in the brains of patients. Curcumin also may delay the degeneration of nerve cells, protect from metal toxicity and improve overall memory in patients.(Ref-Annals).
Clues from Studies
Because no public health authority, such as the Centers for Disease Control or National Institutes of Health, have issued guidelines on the prevention of Alzheimer's disease, it's impossible to provide a strict measure that wards off the disease. The best guidance comes from your health care provider who can tell you whether turmeric or curcumin for therapeutic purposes is right for you. Studies, however, provide some clues about what doses were used to obtain results. First, know that curcumin comprises about 2 to 9 percent of turmeric. Curry powders also have varying levels of curcumin or turmeric, so eating turmeric-containing foods might be an inefficient way of getting the active ingredient. A number of dietary supplements exist to provide the concentrated extract in higher doses, but in many studies, curcumin was injected in participants.
Dosing in Studies
To date, the more than 1,000 published studies on curcumin in animals and people have used a fairly wide range of dosing. The Linus Pauling Institute reports that a six-month study with people taking oral supplements of 4 g curcumin daily was safe. A Chinese animal study reported by the "Annals" authors used an injection of 1 to 2 mg per kg of body weight, but that amount significantly improved neurological deficit and decreased death rates and water content in the brain. The "Annals" authors said that curcumin was labeled "pharmacologically safe" in human clinical trials with doses up to 10 g/daily.
Safety
At high doses, above 10 g, some participants of clinical trials have reported stomach upset, tightness of their chest, skin rashes and swelling. The "Annals" authors also said that chronic use of curcumin can lead to liver toxicity. People with any liver disease, heavy drinkers and anyone on prescription medications --- many of which are metabolized by the liver --- will likely need to avoid chronic curcumin consumption. If you fit in one of these categories, talk to your doctor before you begin a turmeric or curcumin supplement regimen.
References
- "Annals of Indian Academy of Neurology"; The Effect of Curcumin (Turmeric) on Alzheimer's Disease: An Overview; Shrikant Mishra, et al.; Jan./March 2008
- University of Idaho Coeur d'Alene; Understanding the Role of Curcumin in Alzheimer's; June 2011
- Linus Pauling Institute; Curcumin; Jane Higdon; Nov. 2005
- National Center for Complementary and Alternative Medicine: Turmeric
- Alzheimer's Association: Treatments
- ClinicalTrials.gov: Studies on Curcumin and Alzheimer's
