My patients want to look and feel good right now, and that’s my first goal for them. However, I also want them to think about the future. Because believe me—that future creeps up on you faster than you think. (Trust me on this. I just hit fifty, and I could swear that a week ago I was thirty.)

This is why a new medical study caught my attention today. The study reveals that reducing your insulin resistance at any age may slash your risk of developing Alzheimer’s disease. So taking action now—even if you’re only in your twenties, thirties, or forties—might save your life someday.

In case you’re not familiar with insulin resistance, here’s how it occurs. When you eat a diet high in carbs, your blood sugar constantly spikes. As a result, your body has to churn out massive amounts of insulin. Over time, your cells react by becoming insulin-resistant, meaning that they get less responsive to insulin’s message. In effect, they slam the door on insulin and the glucose it’s trying to deliver.

Insulin resistance is a bad thing, because it puts you at risk for obesity and diabetes—and the new study shows that it can harm your brain as well. The study found that insulin resistance reduces the amount of blood sugar in areas of the brain most vulnerable to Alzheimer’s disease, meaning that these areas get less “fuel.”

“If you don’t have as much fuel, you’re not going to be as adept at remembering something or doing something,” study coauthor Auriel Willette says. “This is important with Alzheimer’s disease, because over the course of the disease there is a progressive decrease in the amount of blood sugar used in certain brain regions. Those regions end up using less and less.”

Moreover, he says, it’s not just diabetics who may be at increased risk for Alzheimer’s. In fact, the researchers found evidence that even people with only mild insulin resistance may be at higher risk. And if that doesn’t get your attention, they say that insulin resistance may harm your ability to think at any age.

How can you protect your brain? Simple: Switch from a high-carb to a low-carb diet. Your blood sugar and insulin levels will quickly drop, and your cells will become more sensitive to insulin and start opening the door to it again.

So minimize (or better yet, eliminate) grains. Cut way down on foods like rice and potatoes, too—and cut out sugar entirely. Instead, center your diet around high-quality meat, fish, and eggs, non-starchy veggies, and healthy fats. Add in a few starchy vegetables (like sweet potatoes and beets) and small servings of fruit, but don’t overdo these foods.

And yes, you may miss all those carbs at first. However, you’ll quickly discover that you can go low-carb and still eat gourmet. (Don’t believe it? Check out my recipes here.) Better yet, you’ll be slimmer and healthier—and your brain will thank you, too.

Keep Thinking Big & Living Bold!