What the heck is ketosis anyway?
Ketogenesis has existed as long as humans have. If you eat a very low amount of carbohydrates, you starve your brain of glucose, its main fuel source. Your body still needs fuel to function, so it taps into your reserve of ketones, which are compounds the liver creates from fat when blood insulin is low. This process is known as ketosis: It’s like when a hybrid car runs out of gas and reverts to pure electricity.
“Your liver produces ketones all the time, but the rate depends on carbohydrate and protein intake,” says Jeff Volek, Ph.D., R.D., a professor of human sciences at Ohio State University. When the majority of your diet is made up of of carbs and protein, ketogenesis slows. Replacing carbs and protein with fat will put your body into ketosis, thus ramping up ketone production. This takes about three days to induce.
Can’t you take ketone supplements? No. While it is possible to elevate ketones by taking them, “without the low-carb stimulus, there is no net increase in ketone production, no decrease in insulin, and no net increase in fat oxidation,” says Volek. Don’t trust trainers or “body hackers” who say you can induce ketosis quickly without changing your diet.