How do you monitor ketones? (And how often should you do it?)

As the ketogenic, or keto, diet has become more popular, more patients have asked me about how and when to measure and monitor ketone levels. The answer is highly dependent on why an individual is following this specific diet protocol. Some patients have health indications that benefit from the keto diet. Alternatively, others are strictly utilizing the keto diet for weight loss. For those with medical indications for the diet, monitoring ketones will be more essential.

In the video below, I explain more about ketones and what you need to know about monitoring your ketone levels.

Why you need to monitor ketones

When following the keto diet, the aim is to get the body into ketosis. This is a state during which the body is burning fat because it does not have enough carbohydrates to burn for energy. As a byproduct of the body breaking down its own fat for energy, the liver produces ketones and releases them into the blood stream. Thus, the only reliable way to know if the body is in ketosis is to measure ketones. There are some anecdotal indications that you have entered ketosis, but these are unreliable as a means of monitoring.

When to measure ketones

There isn’t a set guideline for how often I recommend patients measure ketones when following the keto diet. However, I do encourage regular blood testing for the first two weeks to ensure optimal monitoring and efficacy of the diet. Then, patients can often reduce monitoring or utilize at-home kits with urine testing.

How to measure ketones

A blood test will be the most accurate way to monitor ketones. However, daily blood testing can be impractical, so some patients will rely on home urine tests. While these are reliable and easy to use (as well as affordable), they do not have the same level of accuracy. For patients who will benefit from regular daily ketone monitoring, I recommend a device that measures ketones through a breathalyzer type device.