Alzheimer’s disease – what’s high blood sugar got to do with it? A lot actually!1 The idea that chronic or uncontrolled high blood sugar increases your chances of developing Alzheimer’s disease is not breaking news. However, only until recently have we been able to actually understand why this connection occurs. Thanks to a like-minded group of progressive researchers and doctors, the medical community is discovering that the correlation between high blood sugar and Alzheimer’s is more relevant than previously believed.
What makes Alzheimer’s disease (AD) unique to other forms of cognitive decline is the occurrence of protein structures called beta-amyloid plaques and tau proteins. These Amyloid plaques are sticky and eventually accumulate to create blockages in circulation within the brain, essentially killing brain cells. For decades, medical professionals believed these structures were the cause of Alzheimer’s, but new findings have proved otherwise.
The latest medical research has found that this phenomenon is not some erratic cellular dysfunction, but rather an immune response in the brain. Researchers have found that amyloid plaques are surrounding areas of damage or pathogens in the brain as a protective immune mechanism. This monumental finding has led to more pressing questions like what is causing the damage that is setting this immune response in motion.
Enemy #1 – Chronic Inflammation
First, let’s get one thing straight – inflammation isn’t necessarily bad. After all, it’s a critical immune process that kills pathogens and clears away injured or infected cells and tissues. The problem begins when inflammation becomes chronic, and in Western cultures, chronic inflammation is quickly becoming the norm. Our fast-paced lifestyles filled with obligations, overstimulation, fast fixes and even faster meals are often responsible for this detrimental physical state.
Many things can cause inflammation such as:
- Environmental pollution and toxins
- Poor diet
- Food sensitivities
The list goes on, and for most, it’s an everyday occurrence, keeping inflammation prevalent. Diabetes and Alzheimer’s disease are now considered inflammatory diseases.2-3 Inflammation can cause high blood sugar and inflammation has been shown to precede diabetes.3 Inflammation promotes high blood sugar; high blood sugar encourages more inflammation in your body and brain, and this perpetual cycle continues to deteriorate your health. So, how does this affect your brain specifically? Let me explain.
Glucose is your brain’s food of choice.
Your brain may be gaga for glucose, but in order for the cells to utilize it, there must be available insulin— that oh-so-important hormone produced by the pancreas. Insulin must dock on receptors located on cell membranes to signal to the cells that glucose is available and ready for energy production. An interesting find in brains with Alzheimer’s is there are high levels of glucose and insulin circulating, but cells are not able to receive the signals from insulin that glucose is available for fuel. This is where high blood sugar and Alzheimer’s meet.
Chronic inflammation can damage insulin receptors.
When inflammation becomes chronic, this can cause damage throughout the body including the insulin receptors. When these become damaged or weakened, it becomes more difficult for insulin to dock on the cells and help to move glucose from the blood into the cell – this is known as insulin resistance. You will you feel lethargic while your levels of blood sugar and insulin remain high because your body is not receiving the signal to use it.
As your brain cells continue to miss these important signals that glucose is available, they will eventually die. This process triggers an immune response and more inflammation because your brain must now eliminate the dead cells.
Fun fact: Insulin is actually anti-inflammatory, but when the body becomes resistant to insulin, the pancreas reduces production. This response results in even higher blood sugar levels and unregulated production of a pro-inflammatory protein called FOXO1.4
Maintaining a high-sugar diet is a cloying recipe for a health disaster.
A diet high in sugar leads to obesity, which increases inflammation because fat cells produce inflammatory chemicals.5 However, a high-sugar diet, even in the absence of obesity leads to damage to the intestinal lining, the gut microbiome, and endotoxemia, a condition in which toxins are produced in the blood by dangerous bacterial species.6 This kind of diet sets the stage for chronic inflammation leading other chronic health problems.
Is high blood sugar the gateway condition to developing Alzheimer’s disease?
Not all chronic diseases are acquired the same way. Medical researchers understand that diabetes and insulin resistance is just one way to Alzheimer’s disease,2 but they’re not the only way. There are numerous factors that could be to blame for developing Alzheimer’s by causing or perpetuating chronic inflammation; not to mention the genetic factors influencing the brain’s ability to generate and break down beta-amyloid also affect the risk of developing AD.
Everyone is unique. What can help reduce inflammation in one person could perpetuate it in the next. Lifestyle factors, environmental toxins, food sensitivities, and a host of other conditions can cause damage to the brain, evoking the immune response seen in AD. For these reasons, it’s important to find a medical professional who specializes in identifying these root causes of inflammation within your body. From there, they will help you correct these imbalances, reduce inflammation, prevent disease progression and heal damage.
1. Duarte, AI, Santos, MI, Oliveira, CR, Moreira, PI. Brain insulin signaling, glucose metabolism and females’ reproductive aging: A dangerous triad in Alzheimer’s disease. Neuropharmacology. 2018, ISSN 0028-3908.
2. Bredesen DE. Inhalational Alzheimer’s disease: an unrecognized—and treatable—epidemic. Aging. 2016;8(2):304-313.
3. Engström G, Hedblad B, Stavenow L, Lind P, Janzon L, Lindgärde F. Inflammation-Sensitive Plasma Proteins Are Associated With Future Weight Gain. Diabetes. 2003;52(8):2097-2101; DOI: 10.2337/diabetes.52.8.2097)
5. Wellen KE, Hotamisligil GS. Inflammation, stress, and diabetes. Journal of Clinical Investigation. 2005;115(5):1111-1119. doi:10.1172/JCI200525102).
6. Frazier TH, DiBaise JK, McClain CJ. Gut microbiota, intestinal permeability, obesity-induced inflammation, and liver injury. JPEN J Parenter Enteral Nutr. 2011 Sep;35(5 Suppl):14S-20S. doi: 10.1177/0148607111413772. Epub 2011 Aug 1.