By Glenn S. Rothfeld, M.D.
Remember the good old days, when your brain was like a steel trap? You could rattle off names, dates, facts and figures with just a snap of your fingers.
But these days you have enough trouble remembering where you parked the car. And as those “senior moments” start to pile up, you start to worry more and more about Alzheimer’s disease.
The good news is that there’s a way to predict—and stop—Alzheimer’s disease year before it strikes. And it’s as simple as getting your blood sugar and diabetes under control.
Because research has proven that metabolic disorders like type 2 diabetes and Alzheimer’s are often caused by the exact same problems. The two diseases are so linked that some forward-thinking scientists are even calling Alzheimer’s “type 3 diabetes.”
And they’re saying that by preventing diabetes—or by getting a better handle on the condition, if you already have it—you may be able to stop Alzheimer’s from ever taking root.
The stunning links between diabetes and Alzheimer’s
Researchers argued for years about the relationship between diabetes and Alzheimer’s. But, if you ask me, the science is settled by now.
Don’t misunderstand me. There are other ways to get Alzheimer’s, such as over-exposure to toxic metals like aluminum and mercury. But once you’ve been diagnosed as diabetic, you’re sending your risk of Alzheimer’s through the roof.
Ten years ago, researchers looked at the brains of deceased Alzheimer’s patients, and they found up to 80 percent less insulin and insulin receptors. They dubbed this Metabolic Cognitive Syndrome or MCS—the first concrete link between diabetes and Alzheimer’s.1
And in another study, researchers injected a drug that’s known to cause diabetes (called Streptozotocin or STZ) into lab animals’ bloodstreams. They found that the drug caused BOTH diabetes and neurological damage.2
So how exactly does diabetes end up leading to Alzheimer’s? There are at least three links between the diseases that are important to appreciate.
Link #1: Obesity and Alzheimer’s
The first connection between diabetes and Alzheimer’s is pretty easy to understand. As you know, people often develop type 2 diabetes after years of being overweight.
But what you may not know is that amyloid protein is common in the fat tissue we usually associate with obesity. And amyloid plaques are considered a telltale sign of Alzheimer’s.
In short, the more weight you carry around, the easier you make it for these plaques to develop.
Link #2: Low blood sugar starves your brain
Type 2 diabetes can cause wild swings in your blood sugar levels. And when your blood sugar crashes, it causes damage to your brain.
Your brain, like the rest of your body, needs the right amount of sugar for fuel. But unlike other cells in your body, your brain cells don’t store sugar. They need a consistent supply.
So when your blood sugar plummets (a condition we doctors call hypoglycemia), it chokes off a fuel supply to your brain. You get moody and agitated, and have trouble concentrating—some of the same symptoms you’d describe with Alzheimer’s.
Link #3: Insulin problems are like a death sentence for brain cells
When you develop type 2 diabetes, your cells become resistant to insulin, which regulates your sugar levels. Or your body may not be able to make enough insulin to pull sugar out of your bloodstream and deliver it to your cells.
Both of those scenarios can put you on the fast track to Alzheimer’s.
When it comes to your brain, insulin has a very unique job to do. It sends signals that lead to the release of key neurotransmitters, help nerves grow and repair themselves, and keep your brain flexible.
So when you’re not making enough insulin—or your brain’s cells are resistant to insulin—the effect on your memory and thinking skills can be huge.
And as the damage piles up, inflammation occurs—and your body sends out inflammatory messengers, called cytokines. These cytokines can lead to the formation of amyloid plaques and tau proteins that have been linked to Alzheimer’s.
The bright side to the links between brain and blood sugar
Now that we’ve established the relationship between metabolic disorders like diabetes and Alzheimer’s, we can work to keep Alzheimer’s from developing.
For years, I’ve been telling my patients about the lifestyle changes that can prevent diabetes—and now we know that they may help prevent Alzheimer’s too (or, at the very least, lessen its effects).
Avoid diets that are high in sugar and starchy carbohydrates like grains and potatoes—they increase insulin levels in the body, not to mention your weight and risk for heart disease, circulatory problems, and neurodegenerative diseases. You’ll do better on a Paleo-style diet or even a Mediterranean diet—any diet with a lower glycemic index will help to prevent dementia from Alzheimer’s disease. GR
- Accardi et al “Can Alzheimer Disease Be A Form Of Type 3 Diabetes?” Rejuvenation Research 15(2) 2012
- de la Monte and Tong. “Brain Metabolic Dysfunction at the Core of Alzheimer’s Disease” Biochemical Pharmacology 88 (2014)
