Ketosis: A Closer Look at the Safety and Risks (Understanding the Details)


There are always questions surrounding any lifestyle change or diet plan. 

How does it work? How long does it take to get into ketosis? And is it dangerous?

Because a keto diet requires some pretty significant changes in your daily habits, for instance, cutting down carbohydrates to an absolute minimum, one of the most frequently asked questions is, is ketosis dangerous or safe? 

Let’s look at all the advantages and risks of ketosis, and by the end, you’ll know all the details you need to decide whether the keto diet is for you. 

Is Ketosis Dangerous or Safe?

is ketosis dangerous

When talking about the generic scheme of things, for most healthy adults, the answer is yes – Keto is pretty safe for an average person. 

However, like anything else, it poses some risks to people with underlying health conditions. For some, it could have adverse effects, which we’ll look at in more detail shortly. 

The truth of the matter is you are going to experience some side effects when first starting the keto diet. This is while your body adjusts to the lack of carbohydrates and the decrease in calories. 

What is Ketosis?

Ketosis is a metabolic state in which the body breaks down fat stores for energy consumption instead of carbohydrates. 

This happens when you lower your carb intake and consume more healthy fats. These fats come from avocado, salmon, mackerel, nuts, and healthy oils. Our handy guide lets you learn more about what to eat on keto.

It usually takes two to four days for the body to reach ketosis. When you first get there, you might notice some unpleasant side effects, such as bad breath, fatigue, and what some people describe as flu-type symptoms, the keto flu. 

While frustrating and often uncomfortable, these side effects are not usually a cause for concern and are not dangerous. However, if you feel they’re continuous and causing you distress, book an appointment with your physician to rule out any underlying issues. 

Let’s take a look at these symptoms in more detail.

The Symptoms

As we’ve already touched upon, a keto diet will bring on particular symptoms, especially in the beginning. While not usually dangerous, some of them can be off-putting. 

However, it’s worth mentioning that, so long as you’re doing the diet right, these symptoms should disappear within a week or two. So, stick with it if you want to reach your goals. But keep your eye on them, and speak to a doctor or dietician about any health concerns.

Although keto’s been around for many years and is thought to be safe, there isn’t enough evidence yet to suggest whether there are any long-standing effects on the body for people on a keto diet. 

Still, nothing is yet to suggest if anything is damaging from ketosis. Research on this is still a work in progress.

To give you an idea of what to expect from a keto diet, here’s an itemized list of symptoms that usually occur within the first week.

Bad Breath

Okay, this is probably the symptom that puts many people off the keto diet, bad breath

However, you can see this as a positive sign that you’re doing something right, as bad breath indicates that your body has reached ketosis. 

This unpleasant repercussion is because of the increase in acetone released via the breath and urine, and even sometimes via the sweat glands.

Acetone is a byproduct of fat metabolism, and when this is released, so is the odor. Don’t worry too much, though. This is a short-term symptom that should vanish after a couple of weeks. 

The Keto Flu

One of the most common side effects that people claim to experience on the keto diet is what’s known as the keto flu. This presents with general flu symptoms such as fatigue, fever, brain fog, nausea, and headaches.

Although these flu-like effects can make you feel pretty rotten for the first week of ketosis, they’re rarely classed as dangerous and should pass reasonably quickly. 

Fatigue/Decreased Performance

Decreased performance tends to go hand-in-hand with the keto flu and can leave you feeling drained and lacking in energy. 

Again, while this might feel counterproductive and off-putting, it should pass after a few days. 

Muscle Cramping

Some people might experience muscle cramps, specifically in their legs, when in ketosis. This can be painful and discomforting. However, there is often a straightforward reason for this, which is dehydration. 

In the initial phase of ketosis, your body loses a lot of water, which means a lot of vital minerals and a decrease in glycogen. For this reason, you usually lose a lot of weight quickly when you start a keto diet.

The solution? Stay hydrated to avoid health problems such as electrolyte deficiency and kidney-related issues. 

Digestive Issues

When you change your diet drastically, in any case, not just with keto, your digestive system can take a while to readjust. 

One of the main symptoms present is constipation or diarrhea, also called keto poop. This is often down to a lack of fiber and fluid. 

To ensure proper digestion, stay hydrated, and eat plenty of leafy greens and high-fiber vegetables.

Your symptoms should settle down after a couple of weeks and aren’t considered dangerous if monitored correctly. 

What are the Dangers of Ketosis

Although ketosis is recommended as a healthy, positive diet for the most part, some cases may lead to more severe symptoms. 

While uncommon, these side effects should be addressed immediately, and the diet should be stopped. These can include the following:

  • Extreme Dehydration – Failure to drink enough fluids can lead to severe dehydration, which can be fatal if not addressed promptly. Stay hydrated at all times while on a keto diet. 
  • Hypoglycemia tends to occur in the case of elevated liver enzymes, which can happen if you combine the keto diet with some form of medication. Speak to your doctor to avoid complications before starting any new diet if you have any pre-existing medical conditions. 
  • Increased Heart Rate – Although, in most cases, it’s common for the heart rate to be raised in ketosis, it shouldn’t be ignored or left unmonitored. If it becomes a persistent concern, consider increasing your carbohydrate intake. Wearing a monitor such as a FitBit can help you closely monitor your heart rate. 
  • Ketoacidosis – Ketoacidosis is a severe condition associated with people with diabetes. Although this is rarely recognized as a symptom of the keto diet, some studies have shown that, in rare cases, it can occur due to a lack of carbohydrates. 
  • High Cholesterol – Cholesterol should be closely monitored on a keto diet. This is because of the increased saturated fats expected to be consumed. A slight increase should be no cause for concern. However, sudden spikes or significant increases should be addressed immediately. 

Who is at Risk on a Keto Diet?

As we’ve already covered, it’s considered safe for most healthy adults to start a keto diet. 

However, there are some instances in which it’s considered high risk. 

Anyone with the following medical conditions is strongly advised to avoid keto due to the high risk of severe complications. These include: 

  • Liver Dysfunction
  • Muscular Dystrophy
  • Pancreatitis
  • Pregnant or Breastfeeding Women
  • Anyone on medication (this should be discussed with their doctor)
  • Low BMI
  • Porphyria
  • Gallstones
  • Removed Gallbladder

If you have doubts about whether a keto diet poses risks to your health, seek advice from a medical professional before making any drastic changes to your nutritional regime. 

How to Avoid Adverse Side Effects in Ketosis

Although some side effects are unavoidable in ketosis due to the processes happening within the body, you can do some things to reduce symptoms. 

Try the following if you’re concerned about any of the adverse effects of ketosis. 

  • Take Supplements – Supplements can help to replenish lost minerals during the early stages of ketosis.
  • Increased Sodium – Although this might sound counterproductive, lowering your carbs can reduce sodium intake. However, tell your nutritionist how much salt you should consume daily. This should typically be around 2g per day for the average healthy adult. 
  • Go Slow – Before jumping into a full-blown keto diet, spend a few weeks on a low-carb diet instead to ease yourself in and give your body more time to adapt. 
  • Keep Exercise Moderate – Be careful not to overdo it at the gym when new to a keto diet. Extreme exercises can increase fatigue, and your performance may decline for the first few days.
  • Stay Hydrated – In the early stages of ketosis, much of the weight loss is water weight. This can result in dehydration and a loss of vital minerals and vitamins. To avoid adverse effects, drink plenty of water throughout the day.

The Prognosis

So, is ketosis safe or not?

Although ketosis is considered safe, this doesn’t mean it’s for everyone. 

The bottom line is while it might be considered perfectly safe for many, for others, especially those with medical conditions, it can have damaging and, in some cases, severe symptoms. 

Don’t take any risks if you’re unsure whether a keto diet fits you. Speak to your physician before making any radical changes to your diet. 

To minimize any adverse side effects of ketosis, stay hydrated, exercise moderately, check your macros, and take supplements to replace vital minerals. 

It will depend on your physical and general health and personal circumstances as to whether or not you’ll reap the benefits of a keto diet. Still, in most cases, keto is a safe and effective weight-loss diet.