Three ways to outsmart “diabetes of the brain”

I may have made my name as a “diet doctor.” But diabetes prevention has been my true passion for as long as I’ve been practicing medicine. Because as chronic illnesses go, it’s hard to imagine one with a more devastating impact on the entire body.

But what makes this disease even more devastating is the fact that it’s entirely avoidable.

Most cases of diabetes can be prevented simply by maintaining a healthy weight. (Unfortunately, by the looks of the latest obesity statistics, it’s safe to say that not nearly enough people have taken this message to heart.)

But what if I told you that keeping the weight off could be the key to avoiding another deadly epidemic too?

I’m talking about Alzheimer’s.

It may sound too good to be true. But the latest research suggests that obesity, insulin resistance, and cognitive decline are all part of the same destructive domino effect. One that puts your brain directly in the line of fire.

And shielding your brain from attack starts with your bathroom scale. I’ll tell you how to take control of it in just a moment. But first, let’s back up and take a closer look at the relationship between blood sugar and brain health…

An assault on the blood-brain barrier

To understand the link between diabetes and Alzheimer’s, we have to start by talking about microcirculation. This refers to the network of tiny blood vessels and capillaries that deliver oxygen and nutrients to the smallest areas of your body, including your brain.

In your brain, these tiny capillaries are lined with specialized endothelial cells that make up the blood-brain barrier. This barrier acts as a sort of filter—allowing essential nutrients, glucose, and oxygen into the brain while keeping harmful chemicals out.

Your brain uses as much as 80 percent of the oxygen and glucose in your body to operate. But it’s also extremely vulnerable to any potential insults, which is why the barrier needs to be nearly impermeable.

The trouble is, research shows that the blood-brain barrier becomes leaky with age.1 And the damage starts in the hippocampus—the area of the brain critical to memory and learning. It’s also one of the parts of the brain most affected by dementia.

But new research from scientists at the Medical College of Georgia shows that obesity and insulin resistance are implicated in “leaky brain,” too.

A devastating domino effect

Scientists have actually known for a while now that obesity and insulin resistance weaken the blood-brain barrier, allowing substances that shouldn’t be there to break through. But they haven’t known exactly how diabesity triggers these changes.

So, the Georgia researchers turned to mouse models of obesity and insulin resistance to take a closer look. They induced diabetes in mice by altering their diets, which changed glucose and insulin concentrations. And they observed a number of key changes to the brain—none of which are good.2

The first thing they noticed, of course, was a more permeable blood-brain barrier, which allowed larger protein molecules to pass. But that’s not all.

Diabetes also appeared to loosen the junctions of the brain’s endothelium, generating actual holes in the cells of the blood-brain barrier. Pericytes—which are muscle cells that strengthen the brain’s blood vessels—also lost tone and became inflamed. Not to mention, brain cells called astrocytes began to swell. Blood vessels became inflamed—and new, dysfunctional, leaky vasculature began to overtake the hippocampus.

But the researchers also discovered something promising: When they blocked a receptor called Adora2a, they were able to prevent all of these changes… resulting in normal cognition, a strong blood-brain barrier, and no inflammation.

Adora2a resides in the endothelial cells of the blood-brain barrier. This receptor dictates how much comes in to the barrier and how much stays out. But when it’s chronically activated, that’s where the trouble starts.

Researchers aren’t quite sure how obesity triggers this chronic Adora2a activation. But they think it’s the result of a domino effect: One that starts with endothelial stress and increased energy requirements in the brain… and ends with a vicious cycle of inflammation and cognitive decline.

Alzheimer’s disease is type 3 diabetes

Now, I know what you’re thinking: It’s only a mouse study. And you’re right—normally, the results wouldn’t mean much because of it. But in this case, researchers are also connecting dots that previous research on actual human Alzheimer’s patients has already laid out.

In fact, Alzheimer’s is widely considered to be “type 3” diabetes, based on what we’ve discovered about obesity, insulin resistance, and the brain.

Human findings already suggest that preventing insulin resistance could ward off cognitive decline. And why wouldn’t it? After all, diabetes is so deadly in part because it does a number on your microcirculation—causing damage that hits your brain every bit as hard as the rest of your body.

But there are other mechanisms at work, too. We now know that Alzheimer’s impedes your brain’s ability to use sugar for energy—causing glucose metabolism to drop by as much as 40 percent in some areas.

This energy loss—along with the resulting oxidative stress and chronic inflammation—leads the way to both the structural changes and cognitive dysfunction we associate with dementia. And a weak blood-brain barrier is just the beginning.

So it makes sense that helping to restore your brain’s insulin sensitivity might prevent some of these symptoms. And doing so is easier than you may think.

In fact, regular, consistent exercise happens to be one way to do it…

Eight weeks to a healthier brain

German researchers recruited 22 sedentary adults who were either overweight or obese—with an average body mass index (BMI) of 31—and gave them two brain scans. One before completing an eight-week exercise program, which featured basic activities like cycling and walking. And one after.

Researchers measured brain responses to an insulin nasal spray. They also assessed for other key factors—including cognition, mood, and metabolic markers. The goal was to see whether they could improve subjects’ cognitive health by boosting insulin sensitivity in their brains.

And here’s what they found: While the eight-week exercise program only resulted in modest weight loss, the brain benefits were huge.

Brain-based metabolic functions normalized, for one. But physical activity also boosted blood flow to areas of the brain that deal with dopamine-mediated, reward-based learning and motor processes. And subjects reported subsequent improvements in both mood and task-switching—a combination that points to higher executive function overall.3

Results also showed that greater improvements in brain function correlated with higher losses of belly fat. (And this is hardly surprising, given what we know about the inflammatory nature of visceral fat.)

So what does that mean for you? Well, like I’m always telling you, get moving. Start small, and work your way up to the recommended 150 minutes of moderate exercise, or 75 minutes of vigorous exercise, weekly. But don’t expect miracles overnight. Remember, consistency is key. And once you regularly include exercise in your daily routine, you’ll start reaping the rewards.

But that’s not the only way to restore your brain’s insulin sensitivity…

Fight diabetes with the A-List Diet

As I mentioned above, Alzheimer’s represents an “energy crisis” of the brain—one that contributes to both the structural and cognitive dysfunction we associate with dementia. But there’s hope…

Research suggests that your brain can substitute ketones, chemicals generated when your body starts breaking down fat in place of sugar for energy.

As part of another recent pilot study, researchers placed 15 subjects with mild Alzheimer’s on a ketogenic diet for three months. They assessed cognitive function before and immediately after the diet period, as well as a month later, once the subjects resumed their usual diets.

Among these subjects, ten were able to achieve sustained ketosis. (In its simplest terms, ketosis is the metabolic state in which the body starts breaking down fat, rather than sugar, for energy.) And these patients showed significant cognitive improvement when compared to the five patients who didn’t follow the diet closely enough.

Those who achieved sustained ketosis experienced a four-point increase in the Alzheimer’s Disease Assessment Scale-Cognitive Subscale Test (ADAS Cog), which is used to measure memory, language, and praxis (a test used to measure academic skills).4

And while four points may not seem like much, it’s FAR better than any current drug can offer—and is also what experts consider to be “cognitively significant.”

Unfortunately, these improvements disappeared once the patients returned to their normal diets. Which means that—as with most things where your health is concerned—consistency is key.

The good news is, with my A-List Diet—a fresh, delicious, Mediterranean-style ketogenic plan—it’s easy to do. This diet focuses on nutrient-dense, low-carb, high-fat, moderate protein, fresh, whole foods. (You can order a copy of The A-List Diet on my website,

Batten down your brain’s hatches

Last, but certainly not least, improving microcirculation is a must for preventing “type 3” diabetes. And reducing your levels of damaging inflammation is the real key here. Maintaining your weight with regular exercise and my A-List Diet will go a long way towards reining in inflammation.

But I also recommend a few key supplements—most notably, French maritime pine bark extract, otherwise known as Pycnogenol®.

Clinical research has shown that one of the primary ways pine bark extract benefits your circulation is by targeting collagen and elastin, which are the building blocks that line your blood vessels and capillaries.

Unfortunately, collagen and elastin break down over time, which can lead to leaky capillaries and a damaged blood-brain barrier. But 100 mg of Pycnogenol® a day can help your body replenish these two critical substances.

I also recommend:

  • Diosmin, 250 mg per day (in divided doses)
  • Hesperidin, 25 mg per day (in divided doses)
  • Quercetin, 50 mg per day (in divided doses)
  • Arginine, 1,000 mg per day

This regimen will amp up production of nitric oxide—a compound that relaxes blood vessels and capillaries, allowing blood to flow more easily, reducing damage to your endothelium.

On its own, this is a solid lineup to help keep type 3 diabetes at bay—based around maintaining a healthy weight, consistent exercise, adopting a healthy, balanced diet, and smart supplementation. But if you’re concerned about Alzheimer’s or dementia, there are many more things you can do to protect your brain.

For more step-by-step guidance, I encourage you to check out my Alzheimer’s Prevention and Treatment Plan.

To learn more about this innovative online learning tool, or to enroll today, click here or call 1-866-747-9421 and ask for order code EOV3W102.


  1. Montagne A, et al. “Blood-brain barrier breakdown in the aging human hippocampus,” Neuron 2015; 85(2): 296-302.
  2. Yamamoto M, et al. “Endothelial Adora2a Activation Promotes Blood-Brain Barrier Breakdown and Cognitive Impairment in Mice with Diet-Induced Insulin Resistance.” J Neurosci. 2019 May 22;39(21):4179-4192.
  3. Society for the Study of Ingestive Behavior. “Exercise improves brain function in overweight and obese individuals.” Science Daily, 07/09/2019. (
  4. “Boosting Brain Ketone Metabolism: A New Approach to Alzheimer’s” Medscape Medical News, 08/03/2017. (