Is Diabetes Linked to Dementia?
A growing population of Type 2 diabetics means a growing number of people with impaired mental functions. Scientists believe that inflammation causes dysfunction of the tiny blood vessels in the brain, which interferes with the supply of nutrients and oxygen to the nerve cells resulting in declining mental functions. The mechanism is similar to damages to tissues in the legs leading to amputations and in the retina of the eye causing blindness.
Experts claim inflammatory agents are released by fat cells due to their resistance to insulin. But there is a paradox here that I question. The concept of insulin resistance itself is based on the interpretation of reduced sensitivity in fat cells to insulin. In other words, on the one hand, medical scientists say that fat cells are not responding to insulin by virtue of being resistant to it, while actively releasing inflammatory agents because they are resistant. Can these two explanations be reconciled, or is there another explanation for both the presence of cognitive impairment and the release of fatty acids?
In my view, the release of inflammatory agents from fat cells is a response to their walls being stretched to capacity rather than due to insulin resistance. When people overeat and gain weight, they fill their fat cells, and this is the cause inflammatory agents being released. In addition, when your fat cells are full, they can no longer accept fatty acids, so these remain in the blood and your muscles start to burn fatty acids, leaving glucose in the blood. This explains one of the links between diabetes and impaired mental functions.
A New Theory
But I suggest that inflammation is not the only reason that causes impaired mental function in diabetics. Diabetes can also accelerate the process called glycation. Let me explain what this means.
It’s normal for glucose molecules to get attached to many proteins in the body. For example, the A1C blood test measures the percent of glucose attached to red-blood cell (hemoglobin) molecules, with up to 6.5 percent considered normal. This means even with normal levels, a certain amount of glucoses is attached to body proteins. However, when there is too much glucose in the bloodstream, as there is in diabetics, there is an excessive attachment of glucose to proteins on the cells that are in charge of releasing or responding to nitric oxide.
Nitric oxide is a chemical that plays a vital role in regulating the caliber of the tiny blood vessels in the brain, legs and the eye. In particular, the chemical relaxes tiny muscle fibers in the walls of vessels that supply blood to the brain, thus allowing the flow of more blood. The chemical is released by cells lining the inside of blood vessels in response to the forces created by the flow of blood.
In diabetes, glycation could inhibit the release of nitric oxide by making the cells lining the walls of blood vessels non-functional. (This inhibition of the release of nitric oxide is also the cause of erectile dysfunction in men, as it prevents blood from flowing into the male organ.)
This means that the impairment of blood circulation in the brain can happen even before people are diagnosed with Type 2 diabetes and long before the release of inflammatory agents from fat cells. Once started, such cognitive impairment can progress regardless of blood sugar control.
It is obvious that normal blood glucose levels can prevent the appearance of impaired mental function in adults with or without Type 2 diabetes by reducing or eliminating the glycation process. In my book Eat Chew Live, I propose eliminating as much as possible the consumption of grains and grain-flour products—breads, muffins, pastries, cakes, pastas, noodles, pizza, corn, rice, bread stuffing, and sauces made with any of these to normalize blood glucose level and stop the process of glycation.
Don’t be distracted by experts who claim glucose is an important nutrient or that “whole grains” are a good source of fiber because both of these claims have not been verified. First, grains are not an essential source of food for humans who have survived thousands of years without eating cultivated grains. Secondly, your body can easily get the amount of glucose and fiber it needs from fruits and vegetables.
In place of grains, focus on eating fresh foods; including some meats and dairy if you want. Add spices to the food and chew slowly to savor the flavors—and you will find that you can eat your meals with very few grain products. Whole potatoes (not mashed), yams, legumes (beans), and lentils are good substitutes for rice, corn, breads, and other grains.
If you have been recently diagnosed with prediabetes or diabetes, or you have recently started to experience symptoms of memory loss, time is of essence. You want to make the dietary changes I recommend because any intervention has to happen before irreversible structural changes have happened in your nerve cells that cannot be rectified by lowering your blood sugar.