It’s not just overweight seniors who are at risk for diabetes. There are plenty of normal and even slender people walking around with chronic blood sugar imbalances. The path to diabetes starts with imbalances regardless of weight.

And unfortunately, that same path leads to brain disease. As seniors, we can’t afford to take risks with the health of our aging brains. Here’s how high blood sugar affects the aging brain.

The Dreaded Pre-Diabetic Diagnosis

When both my husband and I got lab reports that indicated elevated blood sugar, we were shocked. We are normal weight, athletic seniors who enjoy our desserts once in a while. I never imagined we’d hear the doctor say “pre-diabetic.”

Of course, we took action: we made sure our daily exercise increased. We’ve added more vegetables to meals. I cut out bread and pasta, my husband manages to cut-down. We continue to fast during breakfast time and only eat two meals. The hardest part is cutting down on between-meal and after-dinner treats.

If high blood sugar could happen to us, how easily does it happen to other seniors who aren’t as active or attentive to a good diet? I wanted to learn more about the importance of blood sugar control, and especially the risk for brain deterioration.

Your Brain on Sugar

To learn more about the blood sugar problem and our brains, I turned to a book called Brain Maker: The Power of Gut Microbes to Heal and Protect Your Brain for Life, by Dr. David Perlmutter. This doctor is an expert who encourages a wheat-free, gluten-free diet, even for people who do not test for celiac disease. He stresses the importance of a healthy gut microbiome for maintaining brain health. Here’s what I’ve learned from him about the importance of blood sugar control and the link to brain diseases.

Insulin and Insulin Resistance

To understand pre-diabetes, let’s start with understanding the role of insulin. The hormone insulin is a major factor in metabolism. It is produced in the pancreas and helps shuttle glucose (from eating carbohydrates) from the bloodstream into cells, where it can be used as fuel. When a cell is normal and healthy, it has many receptors for insulin and responds to it. But when a cell is exposed to high levels of insulin because there is a never-ending presence of glucose (from eating too much sugar and carbs), the cell reduces the number of insulin-responsive receptors on its surface.

This causes the cell to become desensitized or resistant to insulin. Once it is insulin resistant, it’s unable to take glucose from the blood. That leaves glucose in the bloodstream.

There is a backup system to fix this because the body can’t deal with excess glucose in the blood. So it tells the pancreas to increase production of insulin to mop up the excess. It will continue to pump out insulin in order to push glucose into cells. But higher levels of insulin are needed because the cells aren’t as responsive to it.

Blood Sugar and Diabetes

This vicious cycle leads to the development of type 2 diabetes. A diabetic is someone who has high blood sugar because their body cannot ferry glucose into cells. If it remains in the blood, that sugar is like an assault weapon and causes a lot of damage.

Diabetes is a leading cause of early death, heart disease, strokes, kidney disease, blindness, and neurological disorders. Researchers are now saying it is a major cause of Alzheimer’s disease, especially if it goes untreated for years.

This road to diabetes and brain disease starts with blood sugar imbalances regardless of weight. This chain of events means that the body endures chronic inflammation in every organ. Excess insulin encourages cellular growth, promotes fat formation and retention, and stimulates further inflammation. It causes other hormones to rev up or turn down, throwing the body’s overall hormonal system off balance.

Blood Sugar and the Aging Brain

Surges in blood sugar have direct negative effects on the brain, effects that cause more inflammation. Blood sugar depletes important neurotransmitters, including serotonin, epinephrine, norepinephrine, GABA, and dopamine. If you are familiar with neurotransmitters, you know they provide vital signals to the brain for energy, mood, motivation, and concentration.

Without adequate neurotransmitters, your brain can’t function well. You may experience brain fog, depression, anxiety, and insomnia. You may get chronic headaches and stomach upsets because blood sugar wreaks havoc to the gut microbiome.

High blood sugar sparks a reaction called glycation, where sugar sticks to protein molecules. These new structures are called AGEs (they can show up as age spots on the skin). Worse, they contribute to inflexible cell membranes. More than any other factor, AGEs contribute to the degeneration of the brain and its functioning. It leads to the shrinking of critical brain tissue.

Insulin resistance can precipitate the formation of the plaques that are present in Alzheimer’s brains. Those with diabetes are at least twice as likely to develop Alzheimer’s disease. Obese people are at a much greater risk of impaired brain function.

To be sure, diabetes doesn’t directly cause Alzheimer’s disease. But the two share the same origin: a dietary onslaught to the body that forces it to adapt by developing biological pathways that eventually lead to dysfunction and, later on, illness. Diabetes and even slight blood sugar issues below the threshold for diabetes are directly associated with increased risk for brain shrinkage and Alzheimer’s disease. ~ Dr. David Perlmutter

What You Can Do

Moderate your carbohydrates for sure. The lower the better. Also eat healthy omega-3 fats. They will counteract the negative effects of unhealthy refined oils and omega-6 fats. Avoid sugar, and it’s derivatives like high-fructose corn syrup. Avoid alcohol because it increases the sugar load to your meals.

If you only strive to do these three things, you will greatly improve your diet and lower your risk for degenerative brain diseases. You have an opportunity at each meal to add to your health and longevity.