Low flavanol diet causes age-related memory decline, finds large study – ScienceDaily

In this study, flavanol intake in older adults was tracked with scores on a test designed to detect normal age-related memory decline, and adults aged 60 years and older with mild flavanol deficiency were assessed for these bioactivities. Supplementation with certain dietary components was found to improve performance on these tests.

“The improvement among study participants on a low-flavanol diet was significant, raising the possibility that flavanol-rich diets and supplements can be used to improve cognitive function in older adults,” said Columbia University Bagueros School of Medicine. says Adam Brickman, Ph.D., professor of neuropsychology at Surgeon and research co-leader.

The findings also add to the emerging idea that just as the developing brain needs specific nutrients for proper development, the aging brain also needs specific nutrients for optimal health. It supports

“The identification of nutrients essential for proper development of the infant’s nervous system was 20 glorious achievements.^th It’s the nutritional science of the century,” said lead authors of the study, Scott Small, M.D., Professor Boris and Rose Katz, professors of neurology at Columbia University Baguellos College of Physicians and Surgeons.

“As we live longer this century, research is beginning to reveal that a variety of nutrients are needed to strengthen the aging psyche. Our study can be used as a template for other researchers to identify additional nutrients.” Nutrients Needed. ”

Age-related memory loss is associated with hippocampal changes

Current research has linked age-related memory loss to changes in a specific region within the hippocampus of the brain, the dentate gyrus (a region essential for learning new memories), and flavanols have been linked to the function of this brain region. has been improved.

Additional research in mice found that flavanols, particularly a bioactive substance in flavanols called epicatechin, improved memory by promoting the growth of neurons, blood vessels, and the hippocampus.

Next, Small’s team tested flavanol supplements on humans. A small study confirmed that the dentate gyrus is associated with cognitive aging. A second large-scale study showed that flavanols improve memory by acting selectively on this area of ​​the brain, with the greatest impact on people who start eating poor quality foods.

In the new study, a team from Columbia University collaborated with researchers at Brigham and Women’s Hospital, who are studying the effects of flavanols and multivitamins in the COSMOS (COcoa Supplements and Multivitamin Outcomes Study). The current study, COSMOS-Web, aims to test the effects of flavanols in a larger group and investigate whether flavanol deficiency accelerates cognitive aging in this area of ​​the brain.

study method

Over 3,500 healthy older adults were randomly assigned to take a daily flavanol supplement (in tablet form) or a placebo tablet for 3 years. This active supplement contained 500 mg of flavanols, including 80 mg of epicatechin, the recommended amount for adults to consume from food.

At the beginning of the study, all participants completed a survey assessing the quality of their diet, including foods known to be high in flavanols. Participants then performed a series of web-based activities designed and validated by Brickman at home to assess the types of short-term memory governed by the hippocampus. The test he repeated after 1, 2 and 3 years. Most of the participants identified themselves as non-Hispanic and white.

More than a third of the participants also provided urine samples that allowed researchers to measure biomarkers of dietary flavanol levels developed by co-authors at the University of Reading, UK, before and during the study. This biomarker will allow researchers to determine whether flavanol levels correspond to performance on cognitive tests, providing a more accurate way to see if participants are adhering to their assigned regimen. (compliance was high throughout the study). Flavanol levels were moderately variable, but none of the participants had severe flavanol deficiency.

People with mild flavanol deficiency benefited from flavanol supplements

Although memory scores in the overall group who took daily flavanol supplements improved only slightly, most of them were already on a healthy diet rich in flavanols.

However, at the end of the first year of taking a flavanol supplement, participants who ate a poorer diet and reported lower baseline levels of flavanols had an average memory score of 10.5% higher than placebo. It was found that it increased by 16% compared to time memory. Base line. Annual cognitive tests showed that the improvements observed at 1 year were sustained for at least an additional 2 years.

The researchers strongly suggested that flavanol deficiency is the cause of age-related memory loss, as flavanol intake was correlated with memory scores, and flavanol supplementation improved memory in flavanol-deficient adults. said that

The results of the new study are consistent with those of a recent study that found that flavanol supplements did not improve memory in a group of people in the range of baseline flavanol levels. Previous studies did not separately examine the effects of flavanol supplements in people with low and high flavanol concentrations.

“Both studies show that flavanols have no effect on people who are not flavanol-deficient,” says Small.

It is also possible that memory tests used in previous studies did not assess memory processes in hippocampal regions affected by flavanols. In the new study, flavanols only improved memory processes dominated by the hippocampus, not those mediated by other areas of the brain.

next step

“It is not yet possible to definitively conclude that low dietary intake of flavanols alone causes memory loss, because we have not done the opposite experiment to deplete flavanols in non-deficient people,” says Small. The professor said, adding that such experiments could be considered unethical.

According to Dr. Small, the next step needed to confirm the effects of flavanols on the brain is a clinical trial to restore flavanol levels in adults with severe flavanol deficiency.

“Age-related memory loss is thought to occur in almost everyone sooner or later, although it varies greatly from person to person,” Small says. “If part of this difference is due to differences in dietary flavanol intake, then people in their 40s and 50s who supplemented with dietary flavanols would see even more dramatic memory improvements.”