Skip to content
Testing For Ketosis With Urine Strips

Testing For Ketosis With Urine Strips

If you are considering trying a keto diet, this guide will cover the biochemistry of ketones and give a quick description of how your body uses and releases these compounds that are so sought after by keto dieters.

What Are Ketones?

Ketones are water-soluble molecules that are produced by your liver in the absence of the availability of glucose. They include the following three molecules – Acetone, Acetoacetate and Beta-hydroxybutyrate.

 The purpose of ketones is to provide your body with an alternative fuel source. When you are on a normal high-carb diet, your body runs mainly on glucose (sugar). But when your body is starved of carbohydrates – for example if you are on a low-carb or ketogenic diet – it runs on fat and turns a portion of it into ketones.

Most cells in your body are able to use fat as an energy source, but your brain can’t. The brain requires ketones in order to survive when glucose is in low supply, and this is one reason why ketones exist.

When ketone levels start to increase, a simple test can detect them in the blood, breath, and urine. Ketone strips detect ketones in the urine. Ketone Urine Strips are the most popular and convenient method to test for ketosis, especially for keto dieters.

So What Are Ketone Strips?

When on a ketogenic diet, your goal is to get into a state of ketosis – an altered metabolic state where the body burns fat instead of glucose for fuel. While in ketosis, your body also makes an abundance of ketones. Ketone testing of urine is the simplest and cheapest way to know whether you are in ketosis or not.

When talking about ketone strips, what most people are referring to are paper test strips that test for ketones in urine.

Ketoacidosis is a life-threatening medical condition where ketones reach dangerously high levels and make the blood acidic. Ketone strips were designed initially for people that suffer from type I diabetes who are at a higher risk of ketoacidosis as a result of their condition. Healthy people are unlikely to be in danger of ketoacidosis so if you are not diabetic you don’t need to be concerned.

When doctors measure blood ketones below is the most common diagnostic method.

Below 0.5 mmol/L – normal

Between 0.5-3 mmol/L – nutritional ketosis

Over 3 mmol/L – high ketone levels

Over 5 mmol/L – dangerously high and indicative of ketoacidosis

What you will notice is that the values used on ketone strips are different from the ones above. With ZestKeto Urine Strips, as with most types, you will be you'll be looking for changes in colour on the strip and comparing these results to the colour chart on the bottle or carton.

With ZestKeto strips, light pink means ketones are present but in small amounts. Dark purple means you're in full-blown ketosis.

How to Use Ketone Strips.

Take the strip from the sealed container and hold it by the end furthest from the colour pad. Then either pee directly onto the part of the strip with the absorptive pad. Alternatively, you can immerse it in a collected urine sample. Then, you wait 15 seconds to a minute for the pad to change colour. Compare the colour on the strip to the colour on the chart you received with the test k and hey presto you have your result!

How Do They Work?

Ketone urine-testing strips have a special chemical absorptive pad on one end. The chemical reagent (usually nitroprusside) changes colour when acids such as ketones are present in the urine. The colour depth change varies depending on the concentration of ketones.

Most of the time, these tests detect acetone, and occasionally acetoacetic. The presence of both is a sure sign you are in ketosis. Beta-hydroxybutyrate, which is the most biologically active of the ketones, is largely present in blood and, unfortunately, ketone strips won't detect it.

Are Ketone Strips Accurate?

Ketone strips are accurate when you're just entering ketosis, that is in the first week or two of a ketogenic diet. This is the time when your body is still adapting to this diet. And in case you didn't know, there is a difference between being in ketosis and being keto-adapted.

Ketosis is a metabolic state characterised by raised levels of ketone bodies; keto-adaptation is when your body is able to use these ketones for energy. More specifically, keto-adaptation is when your ketones start fuelling your brain and fatty acids begin fuelling your muscles.

After keto-adaptation, ketone strips may not be the most accurate way to measure ketone levels. This is because when your body produces more ketones than it is able to use, it passes them out through the urine or breath. However, when ketones are fully metabolised, very few, if any, will appear in the urine.

So long term, ketone strips don't always give you the full story in terms of how many ketones are exactly in your system. They are however cheap and you can use them when just starting a keto diet to see if your ketone levels are rising.

Previous article Craving Carbs On The Keto Diet? 5 Tricks to Overcome It
Next article Keto Flu, What is it and what can you do to minimise the symptoms?