A healthy diet is associated with a significantly lower risk of dementia. The effect is primarily mediated by a slowdown in biological aging.
A new study involving experts from Columbia University has examined the extent to which a healthy diet can slow down the biological aging process and protect against dementia. The results are published in the English-language journal “Annals of Neurology”.
Biological aging influenced?
Previous studies have already shown that people who eat healthily experience a slowing of biological aging processes and are less likely to develop dementia. However, the biological mechanisms underlying this effect are poorly understood, the researchers explain.
“Much of the attention paid to nutrition in dementia research focuses on the way certain nutrients affect the brain. “We tested the hypothesis that a healthy diet protects against dementia by slowing the body’s overall rate of biological aging,” said study author Dr. Daniel Belsky in a press release.
“Testing the hypothesis that biological aging across multiple systems is a mechanism underlying the link between diet and dementia was the logical next step,” adds Dr. Belsky added.
Effects of diet examined
To do this, the team analyzed the data from a total of 1,644 participants in the so-called Framingham Offspring Cohort. All participants were at least 60 years old and did not suffer from dementia at the start of the study. Various nutritional, epigenetic and follow-up data were available for these individuals.
The researchers assessed compliance with the Mediterranean diet as an indicator of a healthy diet. In addition, they determined the speed of aging using a so-called epigenetic DunedinPACE clock. Possible cases of dementia were defined based on the study documents, as were deaths among the participants.
Finally, there were nine examinations during the medical follow-up period, each of which included a physical examination and a blood sample. Neurocognitive tests were also carried out and participants were asked to fill out questionnaires about their lifestyle, reports the research team.
According to the researchers, a total of 140 participants developed dementia during the course of the study.
Aging slowed, risk of dementia reduced
The data analysis showed that better adherence to a healthy (Mediterranean) diet slowed the rate of aging, as measured by the experts using the DunedinPACE values, and significantly reduced the risk of dementia and mortality.
In addition, further calculations showed that a slower DunedinPACE score accounted for 27 percent of the association between diet and dementia and 57 percent of the association between diet and mortality, the research team said.
“Our results suggest that a slower rate of aging mediates part of the connection between a healthy diet and reduced risk of dementia, and therefore monitoring the rate of aging could contribute to dementia prevention,” emphasizes study author Dr. Aline Thomas.
However, part of the connection between diet and dementia remains unclear, which is why further investigations into brain-specific mechanisms are warranted. The experts therefore suggest conducting additional observational studies to investigate direct connections between nutrients and brain aging.
If the observations are confirmed in other population groups, the researchers hope that monitoring biological aging could actually help prevent dementia. (as)
