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If you are following the keto diet to lose weight or manage specific health conditions, you need to know how to identify when your body is in ketosis. Ketosis is when the body will burn its own fat for fuel rather than relying on glucose from the foods you eat. But what are ketones exactly and what does ketosis mean for you?

To achieve ketosis, you need to eat a set balance of protein and fat with a very low carb intake. And the balance may vary from person to person. Measure your level of ketones to ensure that you are able to burn body fat and keep your body running efficiently.

What are ketones?

Ketones are what you’re measuring for when you take a ketone test. But what are ketones exactly?

Ketones, or ketone bodies, are a byproduct of the process of breaking down fat for energy. They can actually supply various parts of the body with energy—including the brain. A boost in ketones can adequately fill the gap of lost carbohydrate intake from a significantly restricted diet.

The body is capable of creating its own energy from fat stores because food sources were not always readily available throughout human development. This process allows the body to prevent starvation during periods of low food availability.

Ketone development can also occur after prolonged periods of exercise. The body will burn through the fuel provided by food consumed before an extended exercise session. Hopefully, you can now answer “What are ketones” and understand how ketones work in your body.

What is ketosis?

Ketosis is the state when your body produces ketones by burning fat and using them for energy. Normally, your body relies on carbohydrates as fuel for regular bodily functions. However, when you switch out carbs for a high-fat diet, ketosis will kick in so that your body can continue to function normally.

When you first begin to follow a ketogenic diet, you may notice that the change has an effect on your energy level and overall sense of wellness.

This adjustment period is normal and in fact has a nickname: keto flu.

When you completely zap your system of glucose by following a low-carb, high-fat diet, you may notice nausea, constipation, headache, irritability, cramps, diarrhea, dizziness, fatigue, insomnia, poor concentration and intense sugar cravings.

However, you can take steps to mitigate keto flu symptoms—stay hydrated, avoid caffeine, ditch sugar and consume more salt to replace electrolytes. Once your body becomes more adapted to the ketogenic diet, you will not notice an onslaught of symptoms every time your body enters ketosis.

What are signs of ketosis?

Simply following the ketogenic diet does not necessarily mean that your body will be in a state of ketosis.

Variations in your diet, such as a meal that’s exceptionally high in protein, can throw you out of ketosis.

In some cases, exercise may also kick you out of ketosis because your body will be demanding more energy, so it will use up any excess of ketones. Also, you can’t rely on keto flu symptoms to indicate that ketosis is occurring. Some people will not have significant symptoms during the initial period of adjustment to the ketogenic diet.

Check out our Free 7 Day Meal Plan to get started on the keto diet and get into ketosis.

The answer to “what are signs of ketosis” is simple:
  • Keto breath. Unfortunately, one of the potential downsides of the keto diet is bad breath. This comes from one of the three compounds produced by ketone bodies as they’re broken down— acetone. As acetone is released, it can produce a metallic, sweet smell. The scent is sometimes described as similar to the aroma of decaying fruit, and it’s more stubborn than your average halitosis. Brushing, flossing and mouthwash will not address the problem. The aroma originates in your bloodstream and is exhaled through your respiratory system. In other words, it’s not actually coming from your mouth, so a clean mouth won’t fix it.
  • Excessive thirst and dry mouth. Increased thirst is very common as the body transitions to ketosis. The body expels excess glycogen and increases urination as insulin levels drop. You can compensate for this by drinking an adequate amount of water and by replacing electrolytes with additional salt intake.
  • Focused mental state and sustained energy. When you are in ketosis, you will not have a crash in energy once your body burns through the food you’ve eaten, which is what occurs with carbohydrate-based energy. As a result, you may notice that you have sharper mental performance that’s sustained throughout the day.

What are the methods of measuring ketones?

While the above signs can be fairly reliable for knowing that the body has entered a state of ketosis, the most accurate way to know is to test the level of ketones in your blood or urine. Breath tests are available, but the technology is still limited. Click here to subscribe

  • Blood tests – Blood tests are the most accurate measure of ketones, but testing kits and the required strips can be expensive. You can easily find diabetes testing kits with electronic readouts for easy use. However, you need to purchase ketone testing strips, not blood sugar testing strips, which are substantially more expensive. One of the advantages of blood testing for ketones: It is the most accurate measure of ketone levels, and it is unaffected by factors such as dehydration.
  • Urine tests – Excess ketones are expelled through your urine, which means that urine strips can be used to test ketone levels. Unfortunately, this type of test is less accurate than blood testing for a few reasons. First, it only measures a specific byproduct of ketones—acetoacetate. Once your body begins to adapt to more consistent states of ketosis, it will produce less measurable acetoacetate, though ketone levels will still be elevated. As a result, tests may measure a lower level of ketones if you are not just starting out on a ketogenic diet. Dehydration can also skew results from a urine test. Less water in your system will make ketone concentrations seem higher. However, urine testing strips are cheap and easy to use.

When should you take a ketone test?

Testing your ketone level is most important when you start out on a ketogenic diet. You should test regularly and sometimes multiple times a day. Especially if you are worried about how a specific meal or dietary habits can affect your levels.

As you adapt to ketosis, you will begin to know how you feel while the body is in this state, so you can more easily rely on symptoms.

If you want consistent, accurate testing over an extended period of time, blood tests will be the most effective option.