9 Early signs of ketosis – How to tell when your body is in ketosis

Early signs of ketosis
  • People in ketosis often experience effects and symptoms as the body changes the metabolic mechanism and tries to adopt the new way of getting energy. 
  • Your body can quickly enter ketosis in about 48 hours to a week if you are on a low carb, high-fat diets, such as the ketogenic diet or intermittent fasting.
  • Test your ketone levels using urine indicator strips, breath, or blood ketone meters. 

What is Ketosis

Ketosis is the natural metabolic process that occurs when your body does not have sufficient glucose for energy, and it burns stored body fats instead. Usually, the body uses body glucose as the primary source of energy. Glucose is obtained from dietary carbs, sugars, and starchy foods. During the digestion process, carbs, complex sugars, and starch are converted into simple sugars.

How does ketosis happen? Glucose, a simple sugar, is used as fuel in the body’s cells and functions. When in excess, it is stored in the liver and muscles in the form of glycogen. If the body’s glucose is not enough, the body devises a mechanism to produce the fuel it needs. The body begins to break down the fat stores and use the glucose from triglycerides – the type of fat found in your blood. Ketones are a by-product of this process, and the liver produces them. 

The acids that accumulate in your blood during ketosis are called ketones, and they are excreted through urine. They are an indication that the body is breaking down fat. High levels of ketones are not recommended as they may poison the body. Therefore, ketosis is the process whereby the body converts fat stores into energy, releasing ketones as a result. 

Keto Diet

Keto is an acronym for ketosis. The keto diet seeks to promote weight loss through ketosis. The Keto diet is characterized by low-carb, high-fat eating fashion. This diet promotes weight loss because people can consume fewer calories without feeling hungry. Below are

Keto diets concentrate on high satiating foods such as:

  • Meat. Poultry and other meats
  • Eggs
  • Fatty fish like sardines, salmon, and lake trout
  • Whole eggs
  • Nuts
  • Avocadoes
  • Low-carb veggies
  • Cheese
  • Fermented foods like yogurt 
  • Chia seeds

So how do you know when your body is in ketosis? In this article, we’ll reveal the noticeable signs that show when your body is in ketosis.

Here are the early signs of ketosis

1. Weight loss

While people may think that this low-carb diet is effective for weight loss, they can only lose weight when in ketosis. You may notice a drop in kilograms the first few days into the keto diet, but this is just a drop in water weight. Actual weight loss may take weeks to occur. 

2. Headaches

Headaches are a result of consuming reduced carbohydrates, especially sugar. Dehydration and electrolyte imbalances cause headaches. Such keto headache lasts from one day to one week, but it could take longer for some people. If the headache persists, seek medical attention. 

3. Increased thirst

Ketosis may cause increased levels of thirst, partly because of the water loss. Likewise, high levels of ketones in the body can lead to dehydration and an electrolyte imbalance. Both of these outcomes may cause complications. Dehydration may cause kidney stones. Drink plenty of fluids to remain hydrated. Seek medical attention if the dehydration persists and if you have dark-colored urine. 

4. Leg cramps and muscle spasms

Leg cramps and spasms could be an early sign your body is entering ketosis, result from dehydration and electrolyte imbalances. Electrolytes are minerals that carry electrical signals between body cells. They include calcium, sodium, magnesium, potassium, and chloride. Imbalances in electrolytes will cause muscle contractions and spasms. 

5. Fatigue and weakness

At the onset of keto diets, people may feel more tired than usual. This is a result of the body-switching from the regular metabolic process. Carbohydrates do provide a quicker load of energy to the body compared to ketosis. Energy levels increase after several weeks into the diet. If you do not experience increased energy levels, then you should seek the help of a doctor.  

6. Stomach upsets

The switch to a ketogenic diet is bound to cause stomach upsets, just like any other diet change. To reduce this stomach upset, increase your intake of water and other fluids. Incorporate non-starchy vegetables and high fiber foods to avoid constipation. You may use a probiotic supplement to support your gut microbiome. 

7. Changes in sleep pattern

A keto diet can cause interrupted sleep patterns and insomnia. This is caused by low serotonin and melatonin, combined with a higher than normal energy level. Serotonin is the primary hormone that stabilizes our moods, sense of well being, and happiness. It affects the whole body as it enables brain cells and other nervous system cells to communicate with each other. 

Melatonin is the hormone that controls your sleep-wake pattern. Its release is connected to the time of day; it increases during dark hours and decreases during the light hours. Disruptions will disappear after the first few weeks, and in the long run, a keto diet will promote deeper sleep and a shorter required sleep time.  

8. Fruity smelling breath

People on a keto diet note that their breath becomes fruity because of the high ketone levels. Ketones leave the body through breath and urine. Ketones such as acetone, benzophenone, and acetophenones are key culprits of bad breath. There is no sure way to reduce the bad breath, but it may diminish with time. Some people may mask the smell by chewing sugar-free gum or brushing their teeth multiple times a day. This breath is also called ‘keto breath.’ 

9. Improved focus and concentration

When you start a keto diet, you may experience headaches and difficulty in concentration. After these symptoms fade, people often experience better alertness and clarity. Focus is stimulated by the conversion of glutamate to GABA. 

Glutamate and GABA are amino acids that act as neurotransmitters that nerve cells use to send signals to the central nervous system cells. GABA impacts behavior, cognition, and the body’s response to stress. Research also shows that GABA helps to control fear and anxiety when neurons become overexcited. Low levels of this amino acid are associated with schizophrenia, depression, anxiety issues, and sleep disorders. 

Use self-testing kits to check for a high level of ketones

Having ketones in the blood is the most definite sign that one is in ketosis. Doctors use urine and breath tests, but they are not as reliable as blood tests. Individuals can also purchase kits for self-testing from pharmacies or online stores. Good enough ketone levels range from 0.5–3 millimoles per liter. People can also use a breath analyzer or indicator strips to check for ketone levels. 


A keto diet aims at reducing hunger and suppressing appetite. If you follow the guidelines and remain consistent, you will reach ketosis.

Although the symptoms will not reveal your ketone levels, they will surely alert you that you are on the journey to ketosis. If you are losing weight and have an overall good feeling, you don’t have to obsess about your ketone levels.