The 12 Most Common Keto Side Effects


The Ketogenic diet, also known as “Keto”  is a very low-carb, high-fat diet that shares many similarities with the Atkins and other low-carb diets. This diet plan involves cutting way back on carbohydrates, to help the body achieve a state of ketosis, in which it has to burn fat (rather than sugar) for energy.

This diet plan promises quick weight loss, but health experts worry about different side effects and complications. Here are the 12 most common Keto side effects.


Sad Young Woman holding her Head

1.“KETO FLU” This is perhaps one of the most well-known Keto side effects. “Keto Flu” includes symptoms like fatigue, nausea, and headache. Some people report that when they start ketosis, they just feel sick. There’s an estimation that about 25% of people who try the Ketogenic diet experience these symptoms, with fatigue being the most common.

Most people already know about the Keto flu, which may occur as a result of the body adapting to the low-carb state. When your body is in ketosis, it means that it is burning fat instead of glucose and that the Keto is working, but, you may not feel so great at first…

 2. HYPOGLYCEMIA – Hypoglycemia is a very common side effect of cutting out carbs. Your body is craving that sugar that it is no longer getting. Some of the symptoms of hypoglycemia include a feeling of hunger, sweating, shakiness, anxiety, nervousness, etc.

3. CONSTIPATION & DIARRHEA Although constipation is typically more common, diarrhea may also manifest while you’re in ketosis. This Keto side effect occurs due to the changes in the microbiome caused by changing your diet.

4. FREQUENT URINATION This Keto side effect is not necessarily a bad thing, but it’s important to understand what is going on with your body while it’s in ketosis. During these first few weeks on the Ketogenic diet, you are going to be flushing fluids as you deplete sugar stores. After that, your body will be maintaining a lower total quantity of water.

Beautiful Young Woman with Flying Hair5. TEMPORARY HAIR LOSS Hair loss can often be attributed to a nutrient deficiency. When starting a new diet, you actually make big changes to the foods you’re eating. For example, protein is one of the biggest building blocks of your hair. You don’t need more than about 7g per pound of your body weight, but, if you’re consuming much lower than this, it’s important to start upping your protein (this may take several weeks). During Keto adaptation, it is also common for your body to require more B Vitamins.

6. KETO BREATH One of the Keto side effects people may complain about is Keto breath.  Keto breath is something that many people experience in the early stages of Keto adaptation. Luckily, this happens only in the initial adaptation phase and tends to wear off within 1-2 weeks.

7. SLEEP PROBLEMS One of the Keto side effects is hypoglycemia which can (further) stimulate the release of cortisol. Cortisol is a hormone which signals the release of stored glucose in the body from the liver and muscle tissue. That can disrupt sleep if this response happens at night and results in either insomnia/ or poor quality sleep.

8. REDUCED PHYSICAL PERFORMANCE During Keto adaptation, you will see a drop in your fitness capacity. It can take around 6 weeks before getting back to your normal physical condition.

Young Girl with Dumbbells in the Gym9. MUSCLE CRAMPS  One of the common Keto side effects people experience in the early phase is muscle cramps. Muscle cramps occur due to mineral imbalances. As you probably know, minerals are crucial for proper nerve impulse conductivity. So…  a muscle cramp is essentially caused by poor hydration and mineral balance.

10. KIDNEY STONES Kidney stones are less common Keto side effects compared with the above mentioned, but, they do happen occasionally. They are often the result of nutrient deficiencies. The most important of these would be potassium.

11. BONE DENSITY CHANGES Luckily, bone density changes are also less frequent Keto side effect, but, may occur in ketosis. Keto should normally be more helpful than hurtful in terms of bone density changes. Eating sugar is much worse than consuming a high-fat diet. Sugar is known to leach calcium from your bones.

12. WEIGHT REGAIN The Keto diet belong to very restrictive diet plans, which are not appropriate to follow long-term. Health experts suggest following more sustainable /balanced diet plans. The problem with this diet plan is that most people will regain a lot of the weight they lost as soon as they go back on carbs. Furthermore, these types of weight fluctuations can contribute to disordered eating,  which can worsen an already unhealthy relationship with food.


Orange half with Measuring Tape on Plate

Some experts say that this diet appeals to people who have issues with portion control and generally – eating too much.  So… In most cases, what they really need is a lifestyle coach or a nutritionist to help them get to the bottom of these issues.

Many health experts are concerned about people on the Keto diet, especially those who try it without the guidance of a doctor or nutritionist. Doctors say that high-fat diets like this one may raise cholesterol levels, and some studies suggest that they increase the risk of Diabetes. And even worse… Various studies like the one presented at the European Society of Cardiology Congress in Munich,  suggest that people on the lowest-carb diets had the highest risk of dying from cancer, cardiovascular conditions, and all other causes (!) supports only healthy & balanced Diet Plans. Instead of choosing popular but risky Diet Plans,  we advise you to go with a diet plan that is backed by solid science. If you want to learn more about losing weight without putting your Health at Risk,  read the following articles:

Mediterranean Diet Meal Plan (with tips and tricks on how to lose weight Fast & the Healthy Way)…

Quick and Easy Fat- Burning Recipes (Metabolic cooking)…

The ultimate Paleo Diet Cookbook…

If you enjoyed my “The 12 most common Keto side effects” article, feel free to leave your comment below….

Please follow and like us:

2 thoughts on “The 12 Most Common Keto Side Effects”

  1. Thank you for sharing this article!
    I was just thinking of the keto diet but of course wanted to know what can be the possible effects in going to this diet.
    It is a very helpful article, i will make sure to take note of it.
    I will also look into the mediterranean diet.
    All the best!

    • I’m glad if my article helped:) Regarding the Mediterranean diet, you will find plenty of useful info on
      Thank you for leaving y/r comment.
      Best regards


Leave a Comment

Follow by Email
Visit Us