Negative Side Effects of Keto

Negative Side Effects of Keto

Now that you know what keto is, let’s get a little deeper. There are some negative side effects to be aware of. Read this so you are aware of them.

Some people assume this diet is extremely dangerous. Perhaps it is because of how quickly you lose weight while on it. Or maybe they have it confused with ketoacidosis, which is a condition that is caused by uncontrolled diabetes. Keto has been proven to have therapeutic effects when it comes to epilepsy, type 2 diabetes and several other chronic conditions. For the most part keto is very safe, but there can be a few negative side effects, particularly in the beginning.

While you are in ketosis, your body burns ketones for energy instead of how it usually burns carbs. This process doesn’t happen instantly. It takes your body some time to transition. Often this is referred to as the induction phase. During this time, there can be some negative side effects. One of them is known as keto flu.


While starting up keto, you may run into some negative symptoms. These symptoms have been described as “keto flu” because they are similar to the symptoms of the flu.

Some of these include:

  • Fatigue
  • Lack of focus
  • Headache
  • Issues Sleeping
  • Nausea
  • Decreased Physical Performance

When these are experienced this can make someone not want to proceed with the ketogenic diet. It is important to remember that this should only last a couple days.

Bad Breath

Unfortunately, bad breath is a very common negative side effect of keto. When blood acetone levels are raised, your body needs to get rid of some of them. This is done through your breath. On top of that, stinky urine is another common side effect. It has a very distinct smell and once you smell it once you will know what it is. Though no one wants bad breath, it is somewhat encouraging because now you know your body is in full-blown ketosis.

Cramping Leg Muscles

Since ketosis is a reduction in water weight, it can cause cramping. Glycogen binds water and when your carb intake is lowered this flushes glycogen out of the body.

Digestive Problems

To put things more bluntly, constipation is very common when on keto. Fortunately we covered this issue in-depth in an article called¬†Can’t Poop on Keto.¬†These usually only last a couple weeks, but for many that can be a couple weeks too long. To address these you can increase your fiber intake and drink more water. Constipation and diarrhea are both very common for people in ketosis. It is nothing to worry about and by monitoring your diet and fiber intake you should be able to manage it.

Increased Heart Rate

There are rare instances where people on keto experience an increased heart rate. Dehydration and low salt intake are two causes of this. Also, drinking a whole lot of coffee can cause it.

If the problem doesn’t go away, increasing your carb intake may be something you need to look at.

If Issues Persist, See a Doctor

While for most people keto is completely healthy, there are rare occasions where it is not. Make sure to drink plenty of water, get the recommended amount of salt, increase the amount of minerals you intake, eat fiber and ease your way into the low-carb diet. By doing this you can usually navigate the negative side effects of keto. When all of these steps are taken it is rare for health issues to persist.

If you are more of a visual learner, here is a video on the tough side effects of people on the ketogenic diet. As an added bonus, the presenter is gorgeous.

Learn about why you can’t poop on keto.

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