Blood Sugar and Alzheimer’s Disease

I was checking out the implications of high blood sugar levels and came across the article Diabetes and cognitive decline. Below is an example of one of the things mentioned in the article.

A study related to cognitive function in women was published in the February 2007 edition of the Journal of the American Geriatrics Society. The researchers examined older women (average age, 72 years) with different levels of cognitive function and found that the strongest factor associated with good cognitive function was lack of diabetes. Women without diabetes were almost twice as likely to have good cognitive function than women with diabetes. Lack of high blood pressure and lack of smoking were also associated with better cognitive function.

Also on the Alzheimer’s Association web page in the article Blood Sugar, I found the following table:

Current guidelines on blood sugar

  • Based on a “fasting” blood test taken at least 8 hours after eating
  • Regular testing should begin at age 45 or earlier in individuals with risk factors in addition to age
Fasting blood sugar


Health impact

Less than 100 milligrams per deciliter (mg/dL)


Healthy level

Between 100 and 125 mg/dL

Prediabetes or borderline diabetes

Increased risk of cardiovascular disease and future diabetes

126 mg/dL or higher, measured on two different days


Risk of damage to the eyes, kidneys, blood vessels, heart and nerves as well as cognitive decline and dementia

If your blood sugar is higher than normal, you should talk to your doctor about the best treatment strategy.

As if I needed one more thing to worry about in my diet – no salt, no fat, no sugar, no simple carbohydrates. I wonder what impact starvation has on the brain.

One should also remember the statistical dictum that “correlation is not the same thing as causation.” Meaning that high blood sugar and mental decline may be correlated but that does not mean that high blood sugar causes mental decline. There is always the possibility that aggressive measures to lower blood sugar may be counterproductive in decreasing mental decline. It is possible that high blood sugar levels are the body’s way of fighting off mental decline. Working to decrease blood sugar level could be fighting the body’s natural defense mechanism. I am not suggesting that the possibility that I am mentioning here is at all likely to be true, but it a cautionary tale on mixing up correlation and causation.

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