If you’ve searched the internet for information about Alzheimer’s you may have read an article or study that refers to it as diabetes of the brain or type 3 diabetes. That’s because insulin resistance is such a strong contributor to the disease. For some people, it’s one of the main contributors, but it’s not the only one.
You also may have read that Alzheimer’s is caused by toxins, brain inflammation, deficiencies of B vitamins, viral or bacterial infections, and many other things. It can get confusing pretty quickly, but the truth is they’re all contributors.
Today’s email is about insulin resistance, a common, modifiable risk factor for Alzheimer’s. It happens when your cells don’t respond well to insulin and can’t absorb glucose from your blood for energy. To make up for it, your pancreas makes more insulin. Over time, your blood sugar level goes up. If goes up high enough, you’ll be diagnosed with type 2 diabetes — if it never gets high enough for that diagnosis but it’s over 100 you’re still pre-diabetic.
The problem with detecting insulin resistance early to reduce the related risk for Alzheimer’s is that high glucose is the standard measure for insulin resistance, but cells can experience insulin resistance even while you have a “normal” or “optimal” glucose level.
That’s because insulin rises to keep blood sugar low, so insulin can increase for years, and cells can become insulin resistant long before glucose levels get high enough for a diagnosis. Unfortunately, the insulin test isn’t a test that doctors routinely order, the doctors rely on glucose. So they don’t catch insulin resistance early, they wait until glucose is 126 then they can diagnose you with diabetes and prescribe the corresponding medication. That’s just the way they do things.
The Homeostatic Model of Insulin Resistant (HOMA-IR) measures the presence and extent of insulin resistance before or after glucose rises above 100. It’s not a test, it’s a calculation using the results of your glucose and insulin tests. Unfortunately, the insulin test isn’t routinely ordered and the HOMA-IR can’t be calculated without it.
Here’s a case in point – a new client who has had Alzheimer’s for several years has signs of insulin resistance but his fasting glucose is in the ‘normal’ range. Here are the results of 3 of several tests recently ordered:
- Glucose – 94 (optimal 70-90)
- Insulin – 19 (optimal 3-5)
- A1c – 5.5 (optimal < 4)
Remember, glucose is the standard measure of insulin resistance. A glucose level of 94 is considered “in range” using the standard reference range which is 70-99. As you can see, his fasting insulin test revealed a high level of 19 — but the standard range is 1-20 so even if an insulin test had been ordered, a result of 19 wouldn’t have been flagged as high. It should still be used to calculate the HOMA-IR.
Once you have glucose and insulin results you can calculate the HOMA-IR. For my client, that result is:
- HOMA-IR – 5. ( optimal < 1) — His glucose level is within the average normal range, but his cells are experiencing significant insulin resistance and that’s a modifiable risk factor associated with Alzheimer’s disease that hasn’t been addressed.
In study after study, insulin resistance is associated with decreased cognitive function over time.
Since it’s such a well-known contributor to cognitive decline and Alzheimer’s, why isn’t fasting insulin, glucose and a HOMA-IR score standard when someone receives a diagnosis — or long before?
Because testing to uncover contributors to Alzheimer’s isn’t mainstream and many of the associated tests aren’t standard, therefore aren’t routinely ordered or covered by many health insurance plans.
In general, Alzheimer’s is diagnosed after symptoms of cognitive decline start interfering with daily life which is far too late in the disease process. It’s typically diagnosed using:
- a cognitive test like the MoCA
- list of symptoms
- a neuropsychological report (sometimes)
- tests related to amyloid or hippocampal volume (sometimes)
Once a diagnosis is made, the doctor prescribes the approved medication for Alzheimer’s treatment that won’t stop the disease. It’s the best medication the doctor has to prescribe, but it doesn’t address insulin resistance or any of the other contributors to cognitive decline, of which there are many.
The good news is that you have a lot of control over most of your risk factors once you’re aware of them and know what to do. There’s plenty of help available for you, you just can’t find it within the traditional medical approach.
Angela Chapman is a Bredesen ReCODE Practitioner, Functional Diagnostic Nutrition Practitioner and Functional Health Educator. If you’re searching for practical ways to protect your brain health and avoid Alzheimer’s disease, her Sunday email is a great resource for you.