Noticing unusual cravings, fatigue, or a sudden weight stall? These could be Signs You’ve Been Kicked Out Of Ketosis. In ketosis, your body burns fat for fuel, producing ketones. Ideally, blood ketone levels stay between 0.5–3.0 mmol/L. However, even a small carb overload—just 50–100 grams—can knock you out. If you’re following a keto diet and wondering why your energy dropped or your progress stalled, you’re in the right place. This article will break down the clear signs, why they happen, and what you can do to fix it fast.
Returning to hunger and sugar cravings
Following a keto diet is all about consuming food with a low glycemic index to prevent spiking blood sugar. Studies showed that consuming sugar or even carbs that are transformed into glucose is directly linked to an increase in insulin levels.
As we know, insulin is the hormone responsible for regulating your food intake, by telling the brain how high is your blood sugar level.
Then, the increase in insulin levels before sugar or carb intake will lower your blood sugar levels. Then, your brain is convinced that you need to eat sweets to balance your blood sugar levels again.
However, people on the keto diet are more sensitive to sugar because of prolonged cuts in carbs. So, glucose deficiency leads to a response higher than in normal individuals.
Despite the effect of insulin, sugar can also affect the brain directly and trigger overeating.
Fatigue and brain fog
Being in ketosis for a while will make you feel the difference in your energy levels when you are out. This may not be obvious to new ketosis dieters, as the ones who have been on ketosis for a while.
Studies proven that sugar consumption is linked to poor cognitive functions. So, being on a keto diet that forbids sugar enhances brain ability and memory.
Unexpected Weight Gain or Water Retention
When you reintroduce carbohydrates after being in ketosis, your body shifts from burning fat to replenishing glycogen stores. For every gram of glycogen stored, the body binds approximately 3 to 4 grams of water. This physiological response can cause sudden weight fluctuations, sometimes resulting in a gain of 2 to 5 pounds almost overnight. It’s important to understand that this weight gain is primarily water, not fat.
A study published in the Journal of Applied Physiology found that athletes switching from low-carb to moderate-carb diets experienced similar rapid weight changes due to glycogen restoration. Therefore, if you notice quick, unexplained weight gain after consuming extra carbs, it’s a strong sign you’ve been kicked out of ketosis.
Digestive Issues
Digestive discomfort is another common clue that you are no longer in ketosis. While the ketogenic diet often improves digestion for many, reintroducing higher amounts of carbs—especially refined ones—can disrupt gut health. Bloating, constipation, and diarrhea can occur as your body adjusts back to metabolizing glucose instead of fat. High-carb foods often contain more fiber or sugars that ferment in the gut, leading to gas and irregular bowel movements.
According to research in Nutrients (2019), dietary shifts between high-fat and high-carb intake significantly impact microbiome composition and digestive function. If you experience sudden bloating or stomach upset, it might be your body’s way of signaling a metabolic shift away from fat-burning.
Loss of Ketosis Breath
One of the telltale signs of ketosis is “keto breath,” a distinct fruity or metallic smell caused by acetone, a type of ketone released through your breath. When ketone production falls, so does this noticeable side effect. Typically, if your ketone levels drop below 0.5 mmol/L, the concentration of acetone in your breath declines as well, and the scent disappears.
A study in Metabolism Clinical and Experimental (2015) noted a strong correlation between breath acetone levels and blood ketone measurements, making this an easy, non-invasive clue. So, if you realize your breath has returned to normal without changes to your oral hygiene routine, it could indicate that you’re no longer in ketosis.
Low Ketone Readings
Testing your blood ketone levels provides one of the most accurate ways to determine if you are still in ketosis. Ideally, nutritional ketosis is defined by blood ketone concentrations ranging from 0.5 to 3.0 mmol/L. If your reading falls below 0.5 mmol/L, it strongly suggests that your body has shifted back to burning glucose instead of fat.
According to a review published in Frontiers in Physiology (2018), consistent blood ketone monitoring is considered the gold standard for individuals following a ketogenic diet. Many affordable home devices make it easy to check your status. A sudden drop in your ketone numbers is a clear, measurable sign that you’ve been kicked out of ketosis and may need to adjust your diet accordingly.
Frequently Asked Questions
How long does it take to get back into ketosis after being kicked out?
It usually takes 1 to 3 days to get back into ketosis, depending on factors like carb intake, physical activity, and individual metabolism. Faster methods include intermittent fasting, increasing fat intake, and doing high-intensity workouts to burn off glycogen stores.
Can stress kick you out of ketosis?
Yes, chronic stress can kick you out of ketosis. Elevated cortisol levels from stress can increase blood sugar, even without eating carbs, making it harder for your body to stay in fat-burning mode.
Does exercise kick you out of ketosis?
Exercise generally helps you stay in ketosis, but extremely intense workouts can temporarily raise blood sugar levels. This spike is usually short-lived and doesn’t permanently kick you out unless paired with high-carb intake.
Can eating too much protein kick you out of ketosis?
Yes, eating too much protein can trigger gluconeogenesis, a process where your body converts protein into glucose. If glucose levels rise too much, it can reduce ketone production and potentially kick you out of ketosis.
Is it bad to be kicked out of ketosis occasionally?
No, being kicked out of ketosis occasionally isn’t harmful for most people. Some even use “carb cycling” intentionally. However, frequent slip-ups can slow fat loss, impact energy levels, and make it harder to maintain metabolic flexibility.
Conclusion
Recognizing the Signs You’ve Been Kicked Out Of Ketosis early can save you time, energy, and frustration on your keto journey. Whether it’s sudden cravings, fatigue, or a plateau in weight loss, your body gives clear signals when it’s no longer burning fat for fuel. By staying mindful of your carb intake, managing stress, and tracking your ketone levels, you can quickly get back on track and keep making progress. Staying in ketosis doesn’t have to be complicated—it just takes a little awareness and consistency.