You are what you eat, so the saying goes, and a recent study is lending some validity to the phrase. Researchers from Iowa State University’s Department of Food Science and Human Nutrition have found that higher levels of a hormone involved in eating and memory formation corresponded to a lower risk of Alzheimer’s disease by 65 percent.
The study, published in the journal Neurobiology of Aging, used data from 287 people. Researchers looked at their levels of the satiety hormone, Cholecystokinin (CCK), which is produced in the intestine after eating and signals to the brain that you’re full. In the small intestine, it aids in the digestion of fats and protein.
The hormone CCK is also found in the brain—specifically, the hippocampus, the brain’s memory center. When researchers measured the CCK levels of those 287 people, they found that people with higher levels of the hormone were 65 percent less likely to have mild cognitive impairment, which is often a precursor to Alzheimer’s.
“It will hopefully help to shed further light on how satiety hormones in the blood and brain affect brain function,” said Auriel Willette, assistant professor at Iowa State University.
The findings confirm what many in the prevention field have been studying: What we eat and when we provide our bodies with food can affect the brain. Nutrition, stressed the researchers, is not just about calories.
“By looking at the nutritional aspect, we can tell if a certain diet could prevent Alzheimer’s disease or prevent progression of the disease,” said Alexandra Plagman, lead author and graduate student in nutritional science.
Because the CCK hormone is triggered by hydrochloric acid, amino acids, or fatty acids, it could be that diets that include foods with those elements—like the Mediterranean and keto diets—might be proven to up the levels of the CCK hormone in the brain.
“The regulation of when and how much we eat can have some association with how good our memory is,” Willette said. “Bottom line: what we eat and what our body does with it affects our brain.”
Diet isn’t the only area of prevention research under scrutiny lately. A recent study on exercise found that any movement—even the moves you make preparing dinner or taking out the trash—can keep thinking skills intact.
“Exercise is an inexpensive way to improve health, and our study shows it may have a protective effect on the brain,” said Dr. Aron S. Buchman, lead author of the study paper and associate professor in the Department of Neurological Sciences at Rush University Medical Center. “People who moved more had better thinking and memory skills compared to those who were more sedentary and did not move much at all.”
Both studies, however, are observational, meaning they draw a line correlating two separate factors, but do not prove that one causes the other.