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Consumption of curry, a multi-herb and spice mixture associated with Indian cuisine typically prepared as a gravy or soup, may be associated with improved cognitive performance in elderly non-demented subjects, according to a study recently published in the American Journal of Epidemiology.1 Although there are numerous types of curry mixtures, they almost always include the rhizomes of the increasingly popular traditional spice turmeric (Curcuma longa).
The study’s authors analyzed data from the Singapore National Mental Health Survey of the Elderly, conducted from February 15, 2003, to March 30, 2004, which collected extensive information on the personal, social, behavioral, and health-related variables and histories of 1,092 Singapore residents over the age of 60. Participants of the survey also completed the Mini-Mental State Examination (MMSE), which measures cognitive function in terms of memory, attention, language, praxis (the performance of an action) and visuospatial ability. The study’s analysis excluded subjects who reported dementia and those who did not complete the MMSE, leaving 1,010 non-demented subjects. The researchers analyzed these subjects’ MMSE scores and their reported consumption of turmeric-rich curry. Curry consumption rates were categorized as “never or rarely” (never or less than once in 6 months), “occasional” (more than or once in 6 months but less than once a month), “often” (more than or once a month but less than once a week), and “very often” (once a week or more, daily). Results for “often” and “very often” were ultimately collapsed into one category.
Only 16% of subjects reported never or rarely eating curry, whereas 41% claimed to consume curry occasionally and 43% consumed it often. Compared with subjects who never or rarely consumed curry, subjects who consumed it occasionally or often showed significantly higher MMSE scores, indicating better cognitive functioning. Comparisons between “occasional” and “often” rates of consumption, however, were not statistically significant. The authors wrote that this is consistent with experimental evidence that low, but not high, doses of curcumin (generally regarded as the primary active phytochemical constituent of turmeric) help alleviate plaque build-up in the brain associated with Alzheimer’s dementia.
This study had several limitations, particularly that other dietary factors were not taken into consideration and that self-reported curry consumption may not have been accurate. The authors write that the study provides “tentative evidence” of an association between curry consumption and improved cognitive functioning, and they encourage further investigations into curry consumption and Alzheimer’s disease in longitudinal studies and studies that further characterize the specific neurocognitive functions that are enhanced by turmeric and/or curcumin.
According to turmeric and curcumin expert Vladimir Badmaev, MD, PhD, vice president of scientific and medical affairs at Sabinsa Corp., a leading manufacturer of standardized turmeric extracts, “This is a timely review since curcuminoids have recently been tested in in vitro, in vivo and clinical studies as promising botanically-derived agents for prevention and treatment of Alzheimer’s dementia (AD). The interesting point of low doses of curry being the most effective in prevention of AD may be further strengthened by a recent review by Aggarwal et al. discussing a study in mice where a diet of 160 ppm [parts per million], rather than 5000 ppm of curcumin, prevented AD-related pathology.2 In addition, the epidemiological data supporting a beneficial role of curry in prevention of AD are supported by a recently published study by Zhang & Fiala et al.3 The results of this study indicate that curcuminoids may restore an innate immune mechanism which is defective in AD patients.” (Badmaev V. e-mail, Dec 13, 2006.)
-Courtney Cavaliere
References
1. Ng T-P, Chiam P-C, Lee T, Chua H-C, Lim L, Kua E-H. Curry consumption and cognitive function in the elderly. American Journal of Epidemiology. 2006;164:898-906.
2. Aggarwal BB, Kumar A, Aggarwal MS, Shishodia S. Curcumin derived from turmeric (Curcuma longa): a spice for all seasons. In: Bagchi D, Preuss HG, eds. Phytopharmaceuticals in Cancer Chemoprevention. Boca Raton: CRC Press; 2005;349-387.
3. Zhang L, Fiala M, Cashman J, et al. Curcuminoids enhance amyloid-â uptake by macrophages of Alzheimer’s disease patients. Journal of Alzheimer’s Disease. 2006;10:1-7.
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