Study shows reduction in characteristic brain plaques
by Craig Weatherby
Last March, researchers at the Department of Veterans Affairs and UCLA reported that a diet high in DHA slowed the buildup of a key marker of the progression of Alzheimer's disease in mice, dramatically. DHA is the omega-3 fatty acid found in high concentrations only in cold-water fish. They found that DHA reduced buildup of the amyloid protein plaques that characterize Alzheimer's (It remains unclear whether these plaques are a cause or result of the disease process).
The new study employed elderly mice genetically programmed to develop Alzheimer's disease. After three to five months—the equivalent of several years in humans—the group fed DHA-fortified chow had 70 percent less amyloid protein plaque in their brains, compared with the control mice, who were fed a more normal, low-DHA diet.
A similar mouse study, published in 2004, indicated that dietary DHA could protect against damage to the synaptic regions that enable brain cell communication, and enhance their memory.
Population studies have linked high-fish diets to reduced rates of Alzheimer's disease. Omega-3 supplements are now undergoing tests in clinical trials with early-stage Alzheimer's patients, and we'll report the results when we hear them.
Last year, the same research team found that curcumin, the yellow pigment in turmeric, appeared to combat Alzheimer's plaques in mice. Researchers have noted the remarkably low rates of dementia among the elderly in India, where turmeric-rich curry powder is a very popular spice mix.
- Lim GP, Calon F, Morihara T, Yang F, Teter B, Ubeda O, Salem N Jr, Frautschy SA, Cole GM. A diet enriched with the omega-3 fatty acid docosahexaenoic acid reduces amyloid burden in an aged Alzheimer mouse model. J Neurosci. 2005 Mar 23;25(12):3032-40.
- Yang F, Lim GP, Begum AN, Ubeda OJ, Simmons MR, Ambegaokar SS, Chen PP, Kayed R, Glabe CG, Frautschy SA, Cole GM. Curcumin inhibits formation of amyloid beta oligomers and fibrils, binds plaques, and reduces amyloid in vivo. J Biol Chem. 2005 Feb 18;280(7):5892-901. Epub 2004 Dec 7.