Doctors have known for a long time that type 2 diabetes and high blood sugar can lead to poor brain health and raise the risk of dementia.
But exactly how this happens has not been fully understood. Now, researchers from the University of Liverpool may have found an important clue.
Their new study shows that spikes in blood sugar after meals—called post-meal hyperglycemia—could be linked to a much higher risk of developing Alzheimer’s disease.
This research used health and genetic data from more than 350,000 people in the UK Biobank, a large database of medical records. The participants were between 40 and 69 years old.
The researchers focused on how the body handles sugar by looking at things like fasting blood sugar, insulin levels, and how much blood sugar rises two hours after eating.
They used a scientific method called Mendelian randomization, which helps researchers figure out if certain traits—like high blood sugar—might actually cause disease. The results showed that people with higher blood sugar after meals had a 69% greater chance of getting Alzheimer’s.
This was a strong finding, and it was not explained by obvious brain damage or changes in brain size. That suggests that smaller, more hidden processes may be involved.
Lead researcher Dr. Andrew Mason said this finding could help shape future prevention strategies. It suggests that people should not only try to keep their overall blood sugar under control, but also pay close attention to how high their blood sugar goes after eating.
Dr. Vicky Garfield, another senior author of the study, added that more research is needed. The team hopes to test their findings in other groups of people and learn more about the biology behind this connection. If future studies confirm this link, it could lead to new ways of preventing dementia, especially in people with diabetes.
So, what can we take away from this? The study shows that even temporary rises in blood sugar after eating might be harmful to the brain over time. This means it’s not just about avoiding diabetes—it’s about keeping blood sugar levels steady, especially after meals.
This could be a major step in preventing Alzheimer’s disease, which affects millions of people worldwide and currently has no cure. Managing blood sugar may be a simple way to protect brain health, and future treatments or guidelines could be developed based on this idea.
In summary, the study highlights how post-meal blood sugar spikes may quietly increase the risk of Alzheimer’s. It opens the door for more research into how food, sugar, and brain health are connected—and it reminds us that good habits after meals could help our brains stay healthier for longer.
If you care about Alzheimer’s disease, please read studies that bad lifestyle habits can cause Alzheimer’s disease, and strawberries can be good defence against Alzheimer’s.
For more information about brain health, please see recent studies that oral cannabis extract may help reduce Alzheimer’s symptoms, and Vitamin E may help prevent Parkinson’s disease.
The study is published in Diabetes, Obesity and Metabolism.
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