Beginning in the 1920’s, the ketogenic diet, or “keto” diet — which involves eating mostly fat and protein as an energy source with low intake of carbohydrates — has been used by many for weight loss and in helping patients with diabetes or epilepsy. But there’s another less-talked about benefit of this diet: ketosis for mental performance.

If you’re experiencing brain fog, lack of productivity, or poor mental performance, ketosis might be a solution for you. We’ll go over some of the ways ketosis can have a positive effect on cognition and may help you be more productive throughout your day.


First, let’s start with a little refresher around ketosis and energy.

The basis of the ketogenic diet is that it uses specially designed macronutrient balance to get a certain response from the body. Those on the keto diet eat normal amounts of protein, higher amounts of fat than the average person, and they keep their carbohydrate intake very low, less than 50 grams per day.

When carb intake is this low, it triggers a response in the body that is similar to how it would act during starvation. Instead of simply utilizing glucose, the primary source of energy, the brains pulls from its alternative energy source: fat. But before fats can be used by the body, the liver has to first convert them to ketone bodies. Then, these ketone bodies are used as energy for the body and brain when there is lack of glucose.

This is how ketosis works. Now that we’ve understood that, let’s talk about how ketosis might be used as an advantage for your mental state and productivity.


The standard Western diet is deficiency in many areas, including the very important essential fatty acids. This is detrimental to health because we need these for the body and brain to function properly.

It’s been known for a while that ketones can benefit those with neurodegeneration issues like epilepsy, Alzheimer’s disease, Parkinson’s disease, and aging-related cognitive diseases. The production of ketone bodies can help in these cases because the brains of people with these problems can’t use enough of the available glucose to handle cognition and perception. A ketogenic diet can then assist by providing a backup source of energy.

The increased fat intake itself from low-carb and keto diets has also been shown to improve brain function in specific ways. For example:

  • During a study published by the American Diabetes Association, type 1 diabetics saw improved cognitive performance and preserved brain function during hypoglycemia after ingesting medium chain triglycerides (derived from coconut oil).
  • Those with Alzheimer’s have seen improved memory scores that might correlate with the amount of ketones levels present.
  • Ketones from a very low-carb diet have also been shown to improve mild cognitive impairment in aging adults.

Now the question becomes: does a ketogenic diet bring a true cognitive advantage for healthy people? And might ketosis encourage better brain health for the average person?

A big element of how a ketogenic diet can offer benefits for brain function of healthy people has to do with its neuroprotective properties. With that, we have to think about the essential fatty acids omega-3 and omega-6, which are crucial for brain health and function.

Most of our brain tissue is made up of fatty acids, so it makes sense that they would be vital for not only the overall health of the brain but also its important functions like learning and sensory execution.

The human body isn’t able to make essential fatty acids on its own, so we must obtain them from the diet; and a healthful ketogenic program can be rich in them. Not only that, the right ratio of omega-3s to omega-6s, typically anywhere between 1:1 and 1:4, is important for brain health. In a typical Western diet, the ratio falls more between 1:20 and 1:40, a recipe for oxidation and inflammation that isn’t helpful for mental wellness.

A benefit of the ketogenic diet is its use of fats that help maintain the proper balance of omega-3s to omega-6s, including:

  • coconut oil
  • olive oil
  • butter
  • avocados
  • animal fats
  • fish
  • eggs

Also, when one is in a ketogenic state, ketones are used by the brain to generate adenosine triphosphate (ATP), the molecule responsible for carrying energy where it’s needed for metabolism within the cells. And although glucose remains the primary source of energy for the body when it’s present, many people aren’t aware that ketones are actually a more efficient energy source than glucose and can reduce the amount of destructive free radicals produced. And in the brain, energy is everything. This helps better protect the brain — and the rest of the body — from oxidative stress, which negatively affects mental performance and brain aging.


An unbalanced diet can lead to lack of mental clarity, showing up as foggy brain, having a hard time remembering important facts, or struggling to stay focused on tasks. These types of symptoms normally involve two factors:

  • Glutamate, a neurotransmitter that promotes stimulation in the body and is vital for brain function and learning
  • GABA (gamma-aminobutyric acid), the main neurotransmitter in the body that reduces stimulation.

Any time you are talking, thinking, or processing information, glutamate is involved. In fact, as intelligence increasing, glutamate receptors on the cells increase.

But like anything in life, too much glutamate doesn’t mean better. Glutamate should be able to convert into GABA, but sometimes the conversion doesn’t occur as well as it should.

Since glutamate is responsible for over 90% of the brain’s synaptic connections, the brain can over-process and won’t have GABA available to assist in reducing stimulation. So if your body has too much glutamate and not enough GABA available, you’ll likely experience brain fog and have trouble concentrating, as well as decreased social behavior and increased anxiety.

Ketones provide the brain with another source of energy and allow it to more efficiently process the extra glutamate into GABA.

So, by helping increase the production of GABA, ketones can then help decrease the amount of extra neurons that are firing in the brain and improve mental focus. This might even help reduce the present of anxiety and stress, which is beneficial for anyone.


Another way ketone bodies may reduce free radicals in the brain is by improving the efficiency and energy levels of the mitochondria, which produce energy for the body’s cells. Ketosis can also help make new mitochondria and increase ATP in your brain’s memory cells. An example of this was shown during a rat study in which those subjects given a diet of mostly ketones performed better in physical and cognitive tests than those fed a high-carbohydrate diet or typical Western diet.

Final Notes on a Ketogenic Diet

With all of this in mind, it’s easy to see why a ketogenic diet might be a good next step for those looking to increase mental performance and clarify.

It’s also important to note that within the first few weeks of starting a ketogenic diet, as your carb consumption is greatly reduced and your body uses up the glucose that’s left over, you might experience some initial mental fog or headaches. This is temporary and usually due to your body flushing out electrolytes from the diuretic effect of ketosis.

To counter any of these side effects until your body adjusts, be sure to greatly increase your water intake — drink, drink, drink. Then you’ll be well on your way to using the benefits of ketosis for mental performance.