Growing older affects every part of the body, including the brain. Most people experience gradual changes in memory and thinking as they age.
These changes are usually mild, but in some people the brain appears much older than expected.
This faster brain aging has been linked to serious conditions such as dementia, Alzheimer’s disease, Parkinson’s disease, stroke, depression, and anxiety.
Researchers from Jilin University and China Medical University wanted to understand why this happens. Their new research points to an unexpected factor that many people can measure during a routine health check: blood glucose.
Glucose is the body’s main source of energy. Every cell needs it, especially brain cells. However, too much glucose circulating in the blood over many years may damage tiny blood vessels, increase inflammation, and interfere with healthy brain function.
To investigate, the research team turned to the UK Biobank. They examined MRI scans from thousands of healthy adults and used machine learning to estimate how old each person’s brain appeared. After testing several computer models, they selected the one that produced the most accurate predictions.
Using this approach, they estimated brain age for more than 37,000 participants. They then compared those results with blood samples and genetic information.
Nine blood substances were linked with brain aging, but glucose stood out above all the others. Participants with higher blood glucose consistently showed brains that appeared older than their real age. Genetic analyses also supported the possibility that glucose contributes directly to faster brain aging.
The researchers found another worrying pattern. Higher glucose levels were associated with an increased likelihood of several diseases affecting the brain, including Alzheimer’s disease, vascular dementia, Parkinson’s disease, stroke, depression, and anxiety.
Higher glucose was also linked with poorer thinking ability, weaker movement, worse mental health, and smaller brain regions on MRI scans.
These findings highlight why blood sugar matters even for people who are not diagnosed with diabetes. Doctors already recommend healthy eating, regular exercise, weight control, and medical treatment when needed to maintain healthy glucose levels. This study suggests those same habits may also help preserve brain health.
The researchers emphasise that their work does not prove that lowering glucose will definitely slow brain aging. Clinical trials are still needed to answer that question. Nevertheless, identifying glucose as a possible modifiable factor gives scientists an important target for future prevention strategies.
If you care about wellness, please read studies about nutrients that could combat inflammation in older people, and essential foods for healthy aging.
For more health information, please see recent studies about the link between processed foods and chronic diseases, and a simple diet change for a healthier life after 65.
The study was published in Molecular Psychiatry.
