ldutko/ShutterStockWhen you think of high blood sugar, you probably automatically associate it with obesity and diabetes. But according to a new study published in Scientific Reports, it can also lead to Alzheimer’s disease, a degenerative condition that affects more than five million Americans now and is expected to affect some 16 million by 2050, with as many as 125 million worldwide.
It’s been known for some time that people with diabetes are more prone to getting Alzheimer’s, but the researchers, from the University of Bath in the U.K., have uncovered a “molecular tipping point” between elevated levels of blood sugar and Alzheimer’s.
Alzheimer’s is caused by a build-up of abnormal proteins in the brain, which create deposits of plaque (clusters of chemically sticky proteins that build up between nerve cells) and tangles (twisted fibers of a protein that form inside dying cells). This damage leads to a gradual breakdown of the brain’s normal functioning. First it affects the memory, but then it damages other functions such as clear thinking, carrying out everyday tasks, and sometimes even the ability to swallow.
With an aging population, it’s not surprising that scientists are working hard to learn more about the causes of Alzheimer’s, looking for ways to slow the disease down, and even prevent it developing.
Here’s how high blood sugar can lead to Alzheimer’s, according to the new findings: In the very early stages of Alzheimer’s, inflammation can be detected in the brain. Normally the body’s immune system would kick in and tackle that inflammation. An enzyme known as MIF (microphage migration inhibitory factor), has a critical role in the immune response and also in the body’s regulation of the insulin that balances blood sugar.
University of Bath scientists worked together with colleagues from Wolfson Centre for Age Related Diseases at Kings College London, comparing the brains of Alzheimer’s patients with healthy brains. They already knew that glucose and its breakdown products cause damage to the proteins in cells (a process known as glycation). They’ve now identified that continuous high blood sugar levels, (e.g. in poorly managed diabetes), interfere with the MIF enzyme that controls the body’s response to the inflammation.
However, Professor Jean van den Elsen from the Department of Biology and Biochemistry, University of Bath, is careful to explain that simply eating too much sugar won’t give you Alzheimer’s. “We haven’t found any evidence that eating a lot of sugar will increase the chances of developing Alzheimer’s disease,” he says. “But we clearly see that if sugar levels stay up for a prolonged time, like in diabetes, there is a chance the increased damage could lead to disease.”
Of course, there are many sound health reasons for avoiding high levels of blood sugar, whether from eating sugary foods or other culprits like refined carbs. In particular, it makes you more prone to developing type 2 diabetes. And with doctors estimating that 8 million Americans are living with undiagnosed diabetes, it makes sense to take precautions such as knowing the symptoms, getting yourself checked regularly, and reducing the amount of sugar in your diet.
Professor Elsen is practicing what he preaches. “I would still advise people that a healthy diet is best. Since I’ve been studying glucose-damaging proteins, I’ve stopped eating added sugar myself as a precaution.”