Flashback Friday: Alzheimer’s Disease – Grain Brain or Meathead?

Below is an approximation of this video’s audio content. To see any graphs, charts, graphics, images, and quotes to which Dr. Greger may be referring, watch the above video.

The rates of dementia differ greatly around the world, from the lowest rates in Africa and India, South Asia, to the highest rates in Western Europe, and especially North America. Is it all just genetics?

Well, the incidence of dementia and Alzheimer’s disease is “significantly lower” for Africans in Nigeria “than for African Americans…in Indianapolis,” for example—up to five times lower.

Alzheimer’s rates for Japanese-Americans living in the U.S. are closer to that of Americans than to Japanese. So, “when people of one ethnic group move…from their homeland to the United States,…Alzheimer’s rates [can increase] dramatically.”

“Therefore, when Africans or [Asians] live in the [U.S.] and adopt a Western diet, their [increase in] Alzheimer’s [risk suggests] that [it’s] not the genetics.”

Unfortunately, one doesn’t have to move to the West to adopt a Western diet. The prevalence of dementia in Japan has shot up over the last few decades. “Mechanisms to explain [this in Japan] include increases in cholesterol, saturated fat, and iron from increases in [the consumption of] animal products. Traditional diets generally…are weighted toward vegetable products such as grains and away from animal products.” But, “[s]ince 1960, the diet in Japan has changed from [a more] traditional [rice-based] diet…to one with a preponderance of meat.”

“From 1961 to 2008, meat and animal fat increased considerably, whereas [the] rice supply [dropped].”

The dietary factor most strongly associated with the rise in Alzheimer’s disease in Japan was the increased consumption of animal fat. A similar analysis in China arrived at the same conclusion.

“On the basis of [these] findings…, the rate of [Alzheimer’s disease] and dementia will continue to rise…unless dietary patterns change to those with less reliance on animal products.”

This is consistent with data showing those who eat vegetarian appear two to three times less likely to become demented. And, the longer one eats meat-free, the lower the associated risk of dementia.

Globally, the lowest validated rates of Alzheimer’s in the world are rural India, where they eat low-meat, high-grain, high-bean, high-carb diets. Now, it’s possible the apparent protective association between rice and Alzheimer’s “is more likely due” to the fact that the drop of rice consumption associated with increasing Alzheimer’s was accompanied by a rise in meat consumption.

But, other population studies have found that dietary grains appear strongly protective in relation to Alzheimer’s disease. In other words, perhaps, don’t pass on the grain; pass the grain, to spare the brain.

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Images thanks to kresbicky via deviant art.