Will Taking Exogenous Ketones Stop Fat Loss?


Would you like to lose some fat? A ketogenic diet is a pretty good tool to help you reach your goal. You can use exogenous ketones which have been a popular way to help get people into ketosis and comply with the transition from eating carbs to eating fats. Once in ketosis, use real food to stay there. Sounds easy, right? 

Unfortunately, some bro science complicating this topic has been surfacing which must be quashed. People are claiming that exogenous ketones are stopping the fat burning that people are seeking. The same exogenous ketones that help a lot of people experience ketosis and make getting into and staying in ketosis much easier, which makes the fat loss so much easier. SAD!

This is how the logic follows from people who don’t really understand physics but like to quote laws of physics to sound fancy like they know how the human body works:

Exogenous ketones contain energy. Body fat is stored energy. Therefore, if you consume any energy, you can’t use any stored energy. 

That’s not really how the body works. At all. 

By that same rationale, if you were to eat any dietary fat (or any food), then you wouldn’t be able to burn any fat. Unless every single person who has ever lost fat has only done so by doing a water fast, I think this argument and concern is pretty invalid. 

So before we get further: NO, exogenous ketones do not stop fat burning. 

Fat loss and fat gain are a little more complicated than people think. I personally don’t believe in the strict calorie in, calorie out model that some people who misunderstand conservation of energy do. Your body is not a bomb calorimeter, so stop telling me that you need to intake a deficit of x amount of calories for y amount of fat loss, people who clearly don’t understand physics (or the human endocrine system). 

Your body has certain efficiencies given certain situations with certain fuels at certain times. This is the same for a car. You wouldn’t expect the same mileage per gallon if you were driving your vehicle like an idiot or certain components of your car are busted. Most people are treating their bodies like this and expecting magic fat loss.

The amount of food definitely does matter, however. Just like that car’s fuel tank can overflow, so can the food down your gullet. Except unlike spilling over and causing a massive fire hazard at a gas station, your body will store (some) of that excess energy as fat. You can’t just overfill the tank and be surprised at gaining fat. However using fat for energy and burning fat is more than just a caloric deficit. 

A ketogenic diet is a really nice way to approach burning fat for fuel. This is where you are using fat for energy. You can get this energy that you burn from outside sources (food you eat) or inside sources (your fat). Just because you eat things, doesn’t mean you can’t lose fat. Quite the contrary. 

On a ketogenic diet, your body starts to prefer more and more fat to be burned for energy. This happens by shuttling more ketones into the cell by increasing the amount of channels (monocarboxylic acid transporters) that can do that. This means if you eat more fat, your body will like to burn it for fuel, and it can more easily use your own body fat for fuel. 

This is where the misunderstood bros will tell you that if you are supplying your body with a scoop of exogenous ketones, that your body will not prefer your own fat for fuel. This is an insane proposition. Your body is pretty damn big and requires a lot of energy. If you think you can fuel this machine exclusively with 10 grams of a substance that it is already using for fuel, and that will in effect shut down any utilization of any other fuel, you are very lost.

The body will simultaneously use your own body fat and exogenous ketones, and believe it or not, some carbohydrates. There is no magic on or off switch. I actually argue that taking exogenous ketones can help with fat burning, not stop it.


Exogenous ketones (supplemental ketones) can actually increase the amount and efficiency of monocarboxylic acid transporters in your cells. This means it is easier for your cells to shuttle in ketones (the ones you can break down from your own fat) to be used for fuel. Easier time burning ketones means more request for fat as energy means more fat burning.

Exogenous ketones can help considerably with food cravings and appetite control as well. This means less overall food, and more fat liberation from your body fat stores. 

Exogenous ketones can provide you with easily accessible energy, which means you would maybe move more. Moving more equals more blood flow, higher metabolism, and more fat burning. 

No, this does NOT mean that exogenous ketones are a magic fat burning pill. You can’t just eat like shit and then use exogenous ketones to erase bad choices. If only.

You should still be eating a nutritional ketogenic diet if you want this to be as easy as possible. You also need to eat real food in rational amounts, move often, sleep well, and decrease stress levels (and over the course of a consistently long period of time) before you are going to be losing any appreciable amount of fat. 

Exogenous ketones are not the enemy here and would probably help the vast amount of people in a well structured fat loss plan for a variety of reasons listed above. 

You didn’t gain all of that body fat overnight, and you’re not going to lose it overnight either. If you want to lose fat, make the right food choices, use a ketogenic diet, move, sleep, de-stress, then repeat. Exogenous ketones are just a tiny tool in that fat loss toolbox.