Can A Temporary Keto Diet Boost Brain Health? A Dementia Researcher Weighs In

We've been fed a lot of ideas that are quite harmful to the brain. 

We've been told that you should eat eight to 10 servings of grains every day and avoid fat—which is exactly the opposite of what your brain needs. Your brain is made out of fat, and its neurons are sheathed in it. It prefers to use fat for fuel over carbohydrates. 

In addition, we've been forced into a lifestyle where we are expected to spend eight hours sitting at a desk and—if you're not one of the employees who are now allowed to work remotely—maybe even driving an hour each way to get to your desk. We don't move enough to circulate nutrients to and waste products away from the brain; our lack of exercise means we also don't create the signaling molecules that tell our brain to stay active and form new connections. 

And we're told that we can sleep when we're dead, meaning that we miss out on hours of cleaning and repairing that keep all our organs, especially our brains, functioning well. 

After all, the brain is a complex system. And while that makes it highly unlikely that any one drug is going to protect the brain from dementia, it is also great news—because it means that there is a broad array of strategies that support brain health. And when you layer these strategies together, you can significantly improve cognitive function.

One of the most important strategies is a nutrient-dense, high-fat, and low-carb ketogenic diet that gives your brain plenty of fuel and reduces harmful byproducts of burning glucose.

Remember, while the brain makes up only 2% of your body weight, it is responsible for over 20% of energy expenditure each day1. With such a high need for fuel, you have to be consuming things that feed your brain, not harm it. You want to give the brain the nutrients it needs to heal, repair your brain tissues, fight toxins, create neurotransmitters, and maintain your neurons.

That means nutrient-dense, lower-carb foods. Nutrients to provide the building blocks, and lower carbs to help stabilize your blood sugar and even out the roller coaster of spikes and drops that create so many cognition-impairing side effects, including lightheadedness, anxiety, fatigue, irritability, and a decrease in focus. 

A healthy diet also fosters the gut microbiome, which then benefits the brain via the gut-brain connection. Your healthy gut bacteria are responsible for aiding digestion, providing a first line of defense for the immune system, and even manufacturing some nutrients and neurotransmitters that the brain needs to function.

More specifically, research shows that ketones—the fatty acids that the body creates when using fat, and not glucose, for fuel—are the brain's preferred form of food and that they help the brain perform better2.

While no one, not even people with severe dementia, need to continually be in ketosis for the rest of their lives, spending three to six months on a ketogenic diet will jump-start the brain's healing in someone who already has cognitive decline. And if you're in prevention mode, spending about a quarter of the year in ketosis—whether that's one week a month, one month a quarter, or two to three days per week—can help elongate your brain span (how many years your brain stays healthy and functional).

The choices you make every day, even the small ones, are what determine your health over the course of your life. If you can decide, I am no longer someone who eats a standard American diet with its high amount of ultra-processed, sugary foods, it will change the trajectory of your health. Or even, I am no longer someone who drinks soda, this can have a profound impact on your health over time.