A new study published recently in the journal PNAS looks at dietary factors as a contributor to the development of different types of dementia including Alzheimer’s disease and accentuates how glucose metabolism declines with the process of aging.
With these findings, the dietary recommendations for adults at high risk for any form of dementia or in general may change as they serve as evidence of how high carbohydrates in the diet can pave the way for dementia and cognitive decline to occur.
Glucose metabolism is fundamental for the functioning of all organ systems in the body as well as of the brain. The brain requires around twenty percent of the energy obtained primarily from the metabolism of glucose or ketone bodies.
This means that malfunctioning in metabolic health can directly affect the brain’s health. Consequently, some people may also develop hypometabolism in which the brain is unable to use glucose as the primary source of energy like it normally does.
Previously, research has identified the drop in glucose metabolic rate in people who suffer from dementia and particularly Alzheimer’s disease. In fact, the higher the drop, the worse the condition of the disease.
In accordance with the statistics from the World Health Organization, around fifty million people at a global level have dementia. The most common form of dementia that is diagnosed is Alzheimer’s disease which makes up sixty to seventy percent of the cases.
Currently, research has not identified the exact cause of the drop in glucose metabolic rate in the brain. However, a number of studies have highlighted that these changes usually occur in the patients before the symptoms of Alzheimer’s begin to appear.
In the new study, researchers explored further on glucose metabolic rate by looking at the communication networks within the brain to detect age-related changes that may occur in the brain.
More specifically, they examined the time the changes begin to appear. Secondly, they also looked at how changes in the diet from high glucose to ketones diet can impact the communication between the regions of the brain.
To investigate further, the researchers assessed data on functional magnetic resonance imaging (MRI) from the Cambridge Centre for Ageing and Neuroscience (Cam-CAN) in Cambridge, UK as well as from Max Planck Institut Leipzig in Germany.
In the data, the researchers looked at more than one thousand scans from people throughout their lives from the age of eighteen to eighty-eight.
By using functional magnetic resonance imaging, researchers and doctors are able to check the brain’s ability to maintain communication between different parts.
In addition to this, the researchers also looked at MRI reports and neural activity of forty-two participants, all of whom were under the age of fifty and did not have a diagnosis of Alzheimer’s disease.
Before having scans, all of the participants followed a normal diet, a low-carb diet, and a diet with intermittent fasting, each for one week. The ketones and glucose levels of the participants were also checked before and after undergoing MRI.
After doing so, it was discovered that the neural activity of the brain was stabilized by ketones and destabilized by glucose in the participants.
Additionally, the researchers also noted that the destabilization of the neural network was associated with a decrease in brain activity as well as cognitive acuity. These changes in neural activity begun at the age of forty-seven and the degeneration of the brain begun after the age of sixty.
The author of the study and professor in the Department of Biomedical Engineering, Mujica-Parodi states:
“The bad news is that we see the first signs of brain aging much earlier than was previously thought,”
However, he also concludes the study by adding “However, the good news is that we may be able to prevent or reverse these effects with diet, mitigating the impact of encroaching hypometabolism by exchanging glucose for ketones as fuel for neurons.”