Testing your ketone levels is the best way to ensure your body is in ketosis, or the metabolic state in which your body burns fat for fuel instead of glucose.
Many who want to remain in ketosis for weight loss, improved focus, and enhanced physical performance make the mistake of simply assuming their bodies are fueling with fat because of their diet . But because it’s possible to consume too much protein, not enough fat, or miss your daily calorie goal, your body may not be in ketosis, even when you think it is.
If you’ve never tested for ketones, this guide will explain what ketones are, how to test for them, and what to do with your results. You’ll be able to fully experience the benefits of ketosis by confirming what metabolic state your body is in through simple ketone testing.
Why should I test for ketones?
Testing your ketone levels is the only way to guarantee your body is in ketosis. If you don’t test, you could find yourself wasting days, weeks, or even months by assuming your body is burning fat when it’s still relying on glucose or protein for energy, canceling out the benefits of ketosis.
You’ll also know if your body is just starting to enter (or possibly exit) ketosis, allowing you to adjust your diet and enter the full depth of the metabolic state. Many ketogenic followers are surprised to learn that they’re not in ketosis when they finally make the decision to test. Save yourself the mistake others have made by testing as soon as you feel you should be in ketosis .
What are ketones?
Our bodies primarily rely on sugar, or glucose, for energy. Our glucose levels rise when we eat carbohydrates. But our bodies can switch to burning fat for fuel when glucose levels dip. While this can happen naturally, the typical American diet makes it rare. To enter ketosis, a diet comprised of 5% carbohydrates, 20% protein, and 75% fat is recommended.
When fed this diet, glucose levels in the body will start to decline. Then, the body makes the switch to using fat as its main fuel source. During this process, fatty acids make their way to the liver. In turn, the organ produces ketones which are then used as energy. When in ketosis, your body produces three different types of ketones .
• Acetate – has the smallest effect on the body and is usually excreted through urine
• Acetoacetate – either used directly for energy or converted into beta-hydroxybutyrate
• Beta-hydroxybutyrate – Not molecularly a ketone, but still treated as one by the body; stimulates growth of new neural tissue and improves brain function
Because the body uses different types of ketones in different ways, it only makes sense that we would test uniquely for each type as well. You can test with just one method or use a combination to confirm your ketone levels. We’ll explore three scientific ways to test and provide a fourth method that can help you decide when it’s time to officially measure your ketone levels.
How to test for ketones
Every testing method has its own pros and cons. Read through the different testing methods to see if there’s one or two that appeal to your preferences.
A blood measurement test for ketosis will measure the presence of beta-hydroxybutyrate in your system. This is considered the most accurate way to test to see if your body is in a ketogenic state. While you can have blood work done at your doctor’s office, a more convenient and affordable way to test is at home with a blood glucose monitor designed to read blood ketones. Here’s how.
1. Clean the area you plan to test (usually a fingertip)
2. Insert a clean needle and draw out a drop of blood
3. Place the blood on a testing strip and wait the recommended time before reading
4. Decipher your results
Blood measurements are measured in millimoles per liter. A low measurement of 0.5 mmol/L suggests that you have very little ketones in your blood. You are either entering or exiting ketosis if your reading falls between 0.6-1.5 mmol/L. You’re in an ideal state of ketosis if your number falls between 1.6-3.0 mmol/L. Your ketone levels are considered incredibly high if your reading is greater than 3.0.
Measuring ketones in your blood will always provide you with an accurate result. This method is also a fast and straightforward way to test. However, the testing strips can be expensive and if you have an aversion to blood or needles, you may want to use a different testing method .
Testing for ketones with your urine will measure the presence of acetoacetate. If your body is producing more ketones than it needs, they’ll enter the kidneys and be excreted in your urine instead of being converted to fat like excess carbohydrates are.
A urine ketone test isn’t always the most reliable. The longer you’ve been in ketosis (or if you’re in a deep ketosis state), your body will be able to utilize ketones more efficiently. Therefore, less will be expelled through your urine. So, a low reading doesn’t rule out ketosis. Because of this, testing with urine is recommended for those who want to confirm they are entering into ketosis and not for those who are trying to monitor a continued ketosis state. Here’s how to test .
1. Remove a clean testing strip from the package
2. Either urinate directly on the strip or place it into a sterile cup with fresh urine
3. Wait the recommended amount of time
4. Compare the color of the strip to the included chart to determine your ketone level
Overall, testing with urine strips is cost effective and quick. But if you’re looking for a long-term testing method, the measurements aren’t always enough to give you an accurate answer to whether or not you’re in ketosis.
Testing your breath for ketones isn’t the most recommended method but it is fast and painless. Acetone is produced by gas in the lungs, so we can use a device to measure the amount that exit the body during exhaling. Most who test by blood and breath find the measurements to be similar. To test your ketones through your breath, complete the following steps.
1. Plug the unit in (or make the its battery pack is charged)
2. Once the unit signals it’s ready, blow into the mouthpiece until the unit flashes
3. Some units link to an app or software that will give you your results. Others utilize a light system. If yours is the latter, green typically means a low reading while red means high. Read the included instructions with your model to determine how it communicates results
The benefits of measuring ketones with your breath is that the testing process is quick. You can reuse your device so despite the initial purchase, it’s a cost-effective test method as well. You also don’t need to use bodily fluids. But reading your results can be difficult, depending on the model you choose. Many also find that measurements can be inconsistent so it’s best to use this method as a secondary or confirmation method .
While far from scientific proof, there are a few symptoms you can look out for to determine if your body is at least headed in the right direction. Many find it helpful to keep a “keto diary” where they record how they feel throughout the day, including when they wake up, after they eat, and before they go to sleep. This is the best way to monitor your symptoms and see exactly how ketosis is affecting you, as the metabolic state is different for everyone.
• Feeling content after meals – One of the biggest issues with a diet high in carbohydrates is that it causes the body to crave more sugar and carbs. As it plows through glucose for energy, the body sends signals to your brain to consume sugar . But when you eat a diet high in fat and limit carbs, your body has a limitless source of fuel as it starts to burn fat. Without a crash in energy, you’ll notice you’re having less cravings and hunger pangs.
• More energy – We’re all familiar with the term sugar rush. When you eat a large amount of carbs, you experience an almost instant burst of energy. But within two hours, the body quickly runs out of energy and starts to feel depleted. But when you’re in ketosis, you should notice that your energy levels stay consistent throughout the day. You’ll skip the afternoon energy dip and power on until it’s time to go to sleep.
• Less brain fog – While many rely on ketosis to burn fat, there are plenty who rely on it simply for the improved focus. For the same reason our bodies fluctuate when it comes to energy throughout the day, the same can happen to the brain. We experience moments of clarification followed by dense brain fog on high-carb diets. But if you’re in ketosis, you should notice that your focus improves and remains consistent throughout the day.
• Feeling thirsty – One uncommonly known side effect of ketosis is thirst or dry skin. As your body enters ketosis, you may notice more trips to the bathroom. This can lead to the beginning stages of dehydration. This is temporary but a good sign that you’re starting to enter ketosis.
If you notice any of these symptoms, it’s safe to start testing as you’re surely entering ketosis. If you start to feel the opposite of some of these symptoms, you may want to test as well as you could be exiting ketosis.
What to do with your results
So now that you’ve tested for ketones, what’s the next step? That depends on your goals. If you’re trying to enter a deep state of ketosis, you’ll want to continue testing at least once per day (depending on the difficulty and cost of your preferred testing method). Keep records of your results so you can see which direction you’re headed.
Once you’ve reached the level of ketosis you’re after (or you’re simply testing to ensure you’re still in ketosis), you can slow down on your testing, as long as you continue with a similar diet and exercise routine. The more you understand your body in ketosis, the less you’ll have to test. You should also test for ketones if you go off your diet, either on accident or during a “cheat day”, or if you notice a significant difference in your energy or weight.
What to look out for when testing for ketones
There is one condition you should keep an eye out for when testing for ketones. If your body begins to produce too many ketones, you could find yourself in an extreme ketonic state known as ketoacidosis. This is more common in diabetic patients but can happen to otherwise healthy individuals as well.
If your blood sugar levels are elevated but your body is still producing ketones, the overall pH in your body can drop to a dangerous level. If left untreated, the condition can turn fatal. The good news is that ketoacidosis is incredibly rare. But should you notice incredibly elevated ketone levels, especially if you’re testing your blood, and notice symptoms like nausea, vomiting, lethargy, or you’re feeling excessively dizzy or confused, seek medical attention. If you’re a diabetic with these symptoms and high ketone levels, seek medical attention immediately.
Tips for getting into keto and remaining there
Not seeing the ketone measurements you were hoping for? For some, entering ketosis takes a bit of trial and error. Try any of the following tips if your ketone measurements are lower than what you had hoped.
• Add coconut oil to your diet – One of the best ways to speed up your entrance into ketosis is to add medium-chain triglycerides to your diet. One of the best (and delicious) sources of these is coconut oil. Use it to cook with, make fat bombs with, or blend into drinks. Just be sure to slowly add it to your diet or you may experience unpleasant digestive side effects like diarrhea or stomach cramping.
• Double check your carbs – You might know the obvious sources of carbs, like breads, potatoes, and white rice. But there are a few sneaky sources that could be creeping in on your ketogenic diet and throwing off your macros. For example, munching on this otherwise seemingly healthy snack could be adding 12 grams of carbs to your diet – carrots. Other less than obvious carb sources are ketchup, artichokes, corn, and fruit. Keep a detailed diary of your meals and snacks for several days. Go back and check every item, even if you’re sure it doesn’t contain any carbs. You may find one or two items that are sneaking carbs into your diet and halting your ketosis.
• Fast – Most people, whether on a ketogenic diet or not, can actually enter the beginning stages of ketosis between meals if they avoid snacks and carbs. Try a quick fast to speed up ketosis. Simply go a few hours without eating and once you start to eat again, focus on a low-calorie daily intake, about 1,000 calories. The majority, up to 90%, of these calories should come from fat. If you consider this approach, make sure you’re closely monitoring your ketone levels so you don’t have to fast for longer than necessary and never fast for more than five days in a row.
• Add more fat – The recommended keto diet may not apply to you. While most focus on 75% fats, you may need to increase yours to 80 % or 85%. At the same time, if you think you’re eating too much fat for your liking, you can lower your percentage to 60% and still be eating a ketogenic diet. With that being said, don’t just focus on fat alone. Make sure you’re consuming high-quality fat. Consider olive oil, butter, tallow, and lard. You’ll want to stay away from processed trans fats found in processed and fast foods.
• Try a supplement – To speed up ketosis, try adding a BHB salt ketone supplement to your routine. All you have to do is add one scoop of the product to a glass of water, drink, and go about your day. A supplement is a fantastic way to either speed up ketosis or quickly get your body back on track after a day of carb binging. You can also utilize supplements when trying our next tip.
• Hit the gym – Whether you use a BHB salt ketone supplement or not, get in a few extra exercise routines to speed up ketosis. A supplement will give you a boost of energy go get through (this one has caffeine as well) but even if you skip the supplement, working out can force your body to use up any residual glucose and start burning fat for fuel.
Measuring your ketones is the smart way to enter ketosis. While you may think you’re following all the rules (and you just may be), your body can sometimes require a bit more of a push. But measuring and monitoring your ketones will have you in your ideal state of ketosis faster, safer, and easier.
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