While it’s not possible to stop the aging of the brain — at least not yet — there may be ways to slow its decline, and a new study shows the crucial role blood sugar levels play in how quickly the brain ages.
The study is the work of an international team of researchers as a follow-up to a 2022 paper that looked at the links between diet and brain atrophy. In previous research, the Mediterranean diet, and especially the green Mediterranean diet (more plants, less meat), was associated with less wear and tear on the brain.
In this new study, the team wanted to explore some of the mechanisms that may be behind this association. They found a significant relationship between markers for lower blood sugar levels and less brain shrinkage and neuron death that typically occurs as we age.
“Maintaining low blood sugar levels, even within the normal range, holds promise for maintaining a younger brain, especially when combined with a healthy diet and regular physical activity,” said study senior author and epidemiologist Iris Shai, van de Ben -Gurion University. in Israel.
Data was collected via magnetic resonance imaging (MRI) brain scans from 224 participants, on average about 51 years old, who had been diagnosed as obese or had high levels of fat in their blood. Over the course of 18 months, they were divided into three groups and then put on a Mediterranean diet, a green Mediterranean diet or a standard healthy diet.
Given that slower brain aging was significantly associated with the Mediterranean diets (particularly the green ones) and lower blood sugar levels, it is likely that all three factors are linked – with the previous 2022 study providing further supporting evidence.
The researchers noticed that volunteers who consumed plenty of green tea and Mankai duckweed shakes as part of the green Mediterranean diet showed the least wear and tear on brain tissue. That suggests there is something about plant foods that protects the brain.
“Specifically, polyphenols found in plant foods can cross the blood-brain barrier and help reduce brain inflammation, which is crucial for memory,” says Shai.
While we can’t infer direct cause and effect from the data, there is strong evidence that Mediterranean diets are good for the brain – as shown in several previous studies. Within this, low sugar levels and high plant content seem to be the main driving forces.
Brain aging is to some extent a natural part of aging, but aging faster means we are at greater risk of cognitive decline and related neurological diseases earlier in life. If we know more about why this happens, we will be in a better position to do something about it, such as changing our diet.
“This trial offers a safe approach to potentially slow the aging of our brains – by adopting the components of a green Mediterranean diet,” said lead study author and epidemiologist Dafna Pachter, from Ben-Gurion University.
The research has been published in the American Journal of Clinical Nutrition.