Yes, having a certain amount of ketones in your blood, urine or breath means that your body is burning fat.
Ketone levels in your blood need to be between 0.5-3 mg/dL for your body to achieve optimal ketosis, which is the ideal state for weight loss. At this point, your hunger hormones reset, leaving you feeling satiated so that you don’t eat as much.
How does ketosis help burn body fat?
Normally, your body uses carbohydrates as a preferred source of energy. However, when the number of stored carbohydrates in your body (stored glycogen in your liver) decreases, this forces your body to turn to using stored fat for fuel
During ketosis, your liver breaks down fats into substances called ketones, which are byproducts of fat metabolism. Ketosis can be achieved by fasting, switching to a low-carb diet, or following a ketogenic (keto) diet (low-carb, high-fat). Combining a keto diet and exercise helps you reach ketosis faster.
When your body is in ketosis, it is burning fat at such high rates that ketones can be detected in your blood, urine, or breath. And the level of ketones indicates the amount of fat being burned. However, to reap the benefits of ketosis without the harmful side effects, ketone levels should still be less than 3 mg/dL.
How can you measure ketone levels?
You can measure your ketone levels during ketosis in one of three ways:
- Urine ketone strips: Urine ketone strips are relatively inexpensive and can give you a rough idea of ketone levels in your body, although results may be slightly inaccurate.
- Blood ketone tests: Blood ketone tests are the most accurate and most expensive way of measuring your ketone levels. They are performed using a kind of blood glucose meter that also helps test for ketones.
- Breathalyzer: A breathalyzer can detect ketones in your breath. Results are less accurate than blood ketone tests but more accurate than urine ketone strips. While the initial cost of a breathalyzer device is pretty high, it’s still a one-time investment that allows you to check your ketone levels frequently without worrying about additional costs each time you want to do a test.
In order to determine what ketone levels are optimal for each type of test, speak to your doctor.
Are there dangers to being in ketosis?
To achieve ketosis, you need to lower your carb intake to less than 50 grams per day. It usually takes about 4-12 weeks to adapt to a keto diet, during which time you may experience what some call “keto flu”—a group of symptoms that may appear as your body adjusts. Symptoms of keto flu include
Drinking plenty of water can help ease or keep some of these symptoms at bay.
Ketone levels higher than 10 mg/dL are dangerous. If you are on a keto diet and feel extreme symptoms of keto flu, you need to keep measuring ketone levels in your body at regular intervals to ensure that they aren’t too high. This is particularly important if you have diabetes or consume a lot of alcohol.
- High ketone levels can lead to a life-threatening condition called ketoacidosis.
Following an aggressive keto diet can also cause dehydration and electrolyte imbalances. If you have conditions such as kidney disease, liver disease, or diabetes, ask your doctor before starting a keto diet.
Health Solutions From Our Sponsors
Cleveland Clinic. What Is the Keto Diet (and Should You Try It)? https://health.clevelandclinic.org/what-is-the-keto-diet-and-should-you-try-it/
Gershuni VM, Yan SL, Medici V. Nutritional Ketosis for Weight Management and Reversal of Metabolic Syndrome. Curr Nutr Rep. 2018;7(3):97-106. https://pubmed.ncbi.nlm.nih.gov/30128963/
Top Do Ketones Mean You're Burning Fat? Related Articles
The 80-20 (or Weekend) DietThe idea here is that you get to splurge a bit if you eat healthy most of the time. Find out more about this approach and what it might do for you.
Beat Belly FatCould your job be to blame for your belly fat? It might be, if it stresses you out. But there are a number of ways to get rid of it.
Ketogenic DietThese are low-carb diets -- the basic idea is to get most of your calories from protein and fat. There are some benefits, but you should be careful with them, especially if you have certain medical issues.
Obesity and OverweightGet the facts on obesity and being overweight, including the health risks, causes, reviews of weight-loss diet plans, BMI chart, symptoms, causes, surgical and nonsurgical treatments, and medications.
phendimetrazinePhendimetrazine is a medication used for short-term treatment of exogenous obesity as part of a weight loss regimen that includes caloric restriction, exercise, and behavioral modification. Do not use phendimetrazine in pregnant or breastfeeding women. Common side effects of phendimetrazine include high blood pressure in the lungs (primary pulmonary hypertension), regurgitant cardiac valvular disease, palpitations, rapid heart rate (tachycardia), reduced blood flow to any of the organs (ischemic events), weakening and thinning of heart muscle (dilated cardiomyopathy), hypertension, flushing, excessive sweating (diaphoresis), dry mouth (xerostomia), nausea, stomach pain, constipation, diarrhea, urinary frequency, painful urination (dysuria), and others.
Top 11 Signs You Are in KetosisKetosis is defined as a natural metabolic process that involves the production of energy from the breakdown of fat into ketone bodies. Signs that suggest you are in ketosis include fatigue, bad breath, dry mouth, weight loss, flu-like symptoms and decreased hunger and thirst.
Weight Loss Challenges: Why Can't I Lose Weight?Finding it difficult to lose weight? It’s a hard thing to do, and there are some surprising reasons you may not be losing weight as quickly as you hope. From sleep cycles to calorie counts, health food fakers to prescription drugs, learn many of the stumbling blocks that can prevent you from reaching your health goals.
Weight Loss QuizAre you trying to lose weight? Take this quiz to see what you can add to routine to get on the right track for results!
What Does High Ketones in Blood Mean?If you have diabetes, high ketone levels in your blood or urine could mean that you have diabetic ketoacidosis, which can be life-threatening. But healthy people on a keto diet may also have high ketone levels but without any significant problems.
What Should I Do If I Have Ketones in My Urine?If your urine reports show moderate or high levels of ketones, consult your doctor right away.
Why Are Ketones Bad?Ketones, also called ketone bodies or keto acids, are a type of water-soluble compound produced from the fat breakdown in the body. Although ketones are a normal product of metabolism, they may be produced in excess in certain situations, such as diabetes.