The Benefits of Wheat Germ for Dementia

Age-related neurodegeneration is blamed on the accumulation of toxic debris within our brain cells, which can be cleared through autophagy, cellular house cleaning that is particularly important for long-lived, hard-to-replace cells, such as neurons. Autophagy can be boosted by the compound spermidine. So, do people who happen to eat more spermidine-rich foods have healthier-looking brains? Yes. Researchers in Germany took MRIs of the brains of older individuals and found that higher dietary spermidine intake was associated with greater brain volumes in dementia-vulnerable regions, such as the temporal lobe, parietal lobe, and the hippocampus, the “memory center” of the brain. Does this actually translate into better brain function? Higher spermidine levels in the blood do correlate with better cognitive performance, leading researchers to suggest that “spermidine plays a major role in the occurrence of senile dementia,” but you don’t know if it’s cause-and-effect, until you put it to the test.

“Restoring Polyamines Protects from Age-Induced Memory Impairment in an Autophagy-Dependent Manner” found that reestablishing youthful spermidine levels through a dietary intervention resulted in an autophagy-mediated restoration of memory performance. But, this was in aging fruit flies. The accompanying editorial was “Spermidine Cures Flies of Senior Moments.” A similar study found that spermidine could also delay brain aging by inducing autophagy in mice, but there was no such study on people—until now.

The SmartAge trial was designed as a randomized, double-blind, placebo-controlled study of a wheat germ extract to see if memory performance can be boosted in older individuals reporting cognitive decline. One of the things I like about it is that the researchers purposefully chose a spermidine dose that could be readily achieved through diet—about 1 mg, which is about a cup of cooked soybeans or a fraction of a single serving of wheat germ. Unfortunately, though the preliminary three-month results found those randomized to the spermidine group had significantly better scores on a test of memory performance, by the end of the year, no significant cognitive benefit was noted. The researchers suggested this failure may have been due to inadequate dosing.

What if you already have dementia? Another randomized, double-blind trial, but this time using more of a whole food. The SmartAge researchers used a wheat germ extract; so, they could fit about a milligram of spermidine into a capsule. Then, they could randomize people to those or identical-looking placebo capsules. That limits the generalizability of the findings, though. Rather than some proprietary extract (particularly one which some of the researchers had a financial interest in), it would be better to test something people could go out and buy at their local grocery store. The problem is that’s a whole teaspoon worth of wheat germ proper, which is harder to hide inside pills. But, you could hide that in a dinner roll, which is exactly what the researchers did.

Older individuals (mostly in their 80s) were randomized to eat rolls made with added wheat germ or identical-looking rolls instead made with added wheat bran. They were to eat one roll a day, six days a week, for three months. Both sets of rolls contained spermidine, but the wheat germ rolls contained 1.4 mg more than the wheat bran ones. Because other foods in their diet had some too, the upshot was a study comparing the effects of increasing your daily spermidine intake 35 percent a day versus increasing it only 20 percent a day. The wheat germ rolls were spermidine-rich enough to significantly raise blood levels, though, whereas the wheat bran ones were not. So, at the end, when the code was broken to see who was eating which rolls, were there differential outcomes in cognitive performance? The researchers reported a “clear correlation between the intake of spermidine and the improvement in cognitive performance in subjects with mild and moderate dementia.” Utilizing the most commonly used cognitive assessment tool, the researchers found that the group with mild dementia getting the wheat germ rolls experienced an improvement that was “way beyond all available antidementia treatments so far.”