Testing for Ketosis

Testing for Ketosis

If you’ve been reading the previous articles then you already know that keto has some incredible benefits for your health, mind and body. But how do you know that you’re actually in ketosis? Well, my friend, allow me to illuminate the possibilities.

Tried & Tested Methods

There are some really cool ways you can get some feedback from your own body to find out if you are in ketosis. Let’s start with physiological signs, the ways in which you can actually see your body responding to the changes that ketosis brings.

Physiological Signs

Increased Thirst, Dry Mouth and More Toilet Trips

When you use fat for fuel, your body needs more water than normal to process the fat. This makes you more thirsty and as your need for water increases you will naturally find your mouth is dry. At the beginning, it can even seem that the more you drink the more you want! But this will usually reduce after the adaption phase.
The more you drink, the more you will urinate too. This thirst and urination increase is often one of the early signs you have reached the desired metabolic state of ketosis. You’ll never be so glad you’re peeing so much as when you’re getting into ketosis.

Bad Breath and Smelly Urine

It’s maybe not the most dinner table friendly topic, but these two are excellent indicators that you have made it into ketosis. When the body uses fat for fuel, it breaks fats down into 3 types of ketones called: acetoacetate, beta-hydroxybutyrate and acetone. In the adaption phase there are more ketones than the body can use, just like a muscle the body needs some training to use up all the ketones effectively.
These excess ketones are excreted in the urine and in the breath and have a characteristic smell, kind of sweet nail varnish remover or the retro candy “pear drops.” In urine it also can have a strong smell, which some have described as smelling like plastic wrapping. These smells are unique to ketosis and are more common during the adaption phase.
Typical bad breath is caused by bacteria and can be reduced by increased brushing or mouthwash. Keto breath is ketones exhaled from your lungs, so the smell, although not unpleasant will remain even if
you brush your teeth. But don’t worry, as your body becomes more accustomed to the new fuel, the keto breath will get better. Note that if your urine starts to smell of ammonia, this could mean you are eating too much protein or not enough fat.

Reduced Appetite

The next key indicator is a loss of appetite. A few days into your keto experience you just may find yourself skipping or even forgetting meals as you just aren’t that hungry.
Cutting out carbs and increasing fat will radically transform your relationship to food and you will simply no longer feel the hunger pangs or desire to eat. Sure, you will still feel that you need SOME food, but it will be a lot less on your mind than before.

Increased Energy

Along with the reduced appetite people typically find they have MORE energy and alertness. This may seem counter intuitive, but trust us, your energy levels will go up as your body is more efficiently able to extract fuel and nutrients from your food.
Right away you will notice that you don’t feel the ‘sleepy slump’ after eating. You may also find you wake up feeling more refreshed in the morning and generally need less sleep, or naps, to keep you going throughout the day

Mental Clarity

As fat becomes your primary fuel source, and your body adapts to the ketones you are producing, there is often an increase in mental clarity. This is due to the increased efficiency of the ketones and calming effect on the brain.
For our ancestors, ketosis signalled they were using up vital stored fuel, so there is an evolutionary genetic adaption to heighten senses and make “cavemen in keto” think and feel better so they could go and hunt down the next meal.

The Technical Approach

Some people prefer a more technical approach so prefer to use at home tests to confirm for sure they are in ketosis. These kinds of measurement methods are really useful when you are just starting out or are unsure about the macros you are eating, but in the long run many people choose to rely on physical signs and knowledge of what they are eating to confirm they are in ketosis.

Urine Test

Since ketones are excreted in the urine and breath and found in the blood these can be tested to confirm ketone levels. Urine ketone levels are easy to check with a ‘Ketostrip’ or ‘Ketostick’ which you dip into your urine. However, dehydration can cause false positive results.

Blood Test

BLOOD ketones can be measured with a special meter and a drop of blood. Beware of getting cheap meters as the results may not be accurate. You can also get meters which measure both blood glucose and ketone levels. This is useful if you are monitoring diabetes or are an athlete carb-loading for a Cyclical Ketone Diet.

Breath Test

BREATH ketones can also be measured with a specialist meter which are slightly more expensive but are more convenient as you don’t need to make yourself bleed.


  • These 5 signs help you spot when you’re in ketosis: thirst, smell, appetite, energy & clarity
  • You can use technical methods to measure if you’re in ketosis: a urine test, blood test or breath test

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