Enhanced brain function is another reason why a "keto" diet has been whisked back into popularity. Studies show that your brain can run almost 25% more efficiently when using ketones as fuel vs glucose. Studies also state that elevated blood ketone levels can improve memory function, as well as increase ATP concentrations and the number of hippocampal mitochondria in the brain of mice by up to 50%.
There are even studies suggesting that Parkinson's and Alzheimer's disease result from impaired glucose tolerance (sometimes called type 3 diabetes). If this is true, then ketones can provide an alternative fuel source for your brain and improve cognitive function.
Inflammation is largely believed to be a root cause of many metabolic diseased states, including obesity, Parkinson's and Alzheimer's disease. BHB has been shown to decrease the inflammasome NLRP3, a pro-inflammatory protein that responds rapidly to things like toxins, infections, injuries and too much glucose.
Performance enhancement is can be the result of reconfiguring your body to run on ketones instead of glucose. Part of the theory for that has to do with the fact that ketones like BHB can provide greater enthalpy (heat of combustion, energy for Krebs cycle) per 2c carbon units vs pyruvate, the end product of glycolysis. In fact, ketones are readily oxidized in skeletal muscle tissue, which causes a glucose sparing effect.
Studies show that elite athletes on a ketogenic diet experience longer time to exhaustion during moderate-intensity exercise (60% VO2 max), as well as no difference in high-intensity exercise. This essentially means there was no loss of performance when following a ketogenic diet vs traditional high carb diet in elite athletes.