After my talk, I became curious and reviewed the literature on whether curcumin (the bioactive component of turmeric, used in day-to-day cooking and Ayurvedic medicine for centuries) could protect against this horrible disease where the sufferer is robbed of memory, feelings and personality. This is a disease where the suffering is just as horrible for the people taking care of the patient. And while there's one FDA-approved medication (Aricept) that seems to slow down progression by about 9 months, there is none that reverse the disease.
So I was excited to read the research on on mice models of Alzheimer's, which tell of curcumin actually reversing one of two likely causes. The current consensus is that the two causes of Alzheimer's dementia are (1) increased production and accumulation of a protein named Amyloid-beta 42 around brain cells, and (2) accumulation of another protein named tau tangles inside brain cells, both of which evoke an inflammatory response leading to the eventual death of these brain cells.
Gary Cole, Ph.D., a UCLA researcher, has shown in vitro experiments (such as in petri dishes in the lab) and in mice that curcumin has 3 major effects that appear to fight the Amyloid cause of Alzheimer's: it (a) breaks down Amyloid-beta so that it doesn't accumulate, (b) prevents the protein from forming, and (c) helps reduce how much cholesterol is available in the brain.
By the way, to see what Alzheimer's disease does to a person's brain, look to the right. Clearly, you can see that brain tissue is destroyed, thus shrinking the size of the brain. (The picture is courtesy of Alzheimer's Association.)
Alzheimer's related advice is found here: http://alzheimer.neurology.ucla.edu/diet.html
Because the published research is based on tissues in the lab and mice, perhaps we should be cautious of wholeheartedly endorsing that curcumin can actually reverse the Amyloid cause of Alzheimer's in people. Luckily, a UCLA team is beginning a curcumin trial in people to study whether it has the same kind of anti-Alzheimer's effects that were seen in mice fed curcumin. The study started this spring (March 2012) and will go on for at least 5 years. (Studies looking at slow-going processes like buildup of Amyloid in the brain take a long time to conduct.)
After putting away some of these interesting papers, I remembered learning (thanks to this World Health Organization webpage) that India has among the lowest rate of Alzheimer's disease in the industrialized world. Since we know South Asians have eaten turmeric on a daily basis for centuries (many still do), perhaps this could be another piece of evidence supporting the anti-Alzheimer's effect of turmeric. So if you have some curry powder in your food most days of the week, keep on doing it. If not, add a dash to whatever you eat next time.