Last modified on October 27th, 2022
Is keto dieting safe? The short answer is that yes, it typically is, but there are exceptions. Certain groups of people shouldn’t try the keto diet.
Before starting any diet, including keto, you should also get the all-clear from your doctor or health care provider.
Below, we talk more about the diet in general and what you should know. We also answer, “is keto dieting safe.”
Key Takeaways—Is Keto Dieting Safe?
We got into more details below, but to quickly sum up and answer the question “is keto dieting safe,” consider the following:
- Is the diet safe? For most people, the keto diet is safe
- However, the keto diet can cause nutrient deficiencies and kidney stones
- Other risks of the keto diet can include low blood pressure and constipation
- If you take diabetic medicine and it causes low blood sugar, you may need to have those adjusted by your health care professional if you start the keto diet
- When you first start this way of eating, you might experience the keto flu, but the symptoms will subside.
- If you have a condition involving your gallbladder, liver, pancreas, or thyroid, the keto diet might not be safe for you. Speak to your doctor.
- If you have a history of disordered eating, any restrictive diet may not be a safe option.
- A ketogenic diet may only be a viable option for a short period of time for some people because it is restrictive and perhaps not sustainable.
The Basics of a Ketogenic Diet
The ketogenic diet, or keto for short, is one of the most popular eating methods.
There are certain benefits of the diet, but also potential risks.
With a keto diet, you consume very limited or even no carbohydrates. Then, the goal is to get your body into a state of ketosis. Ketosis is when ketones build up in your bloodstream. When you have low carb levels, your blood sugar drops. Your body then starts to break down fat to use as energy.
Ketosis is a mild version of ketoacidosis. Ketoacidosis is a dangerous condition that can be deadly when it affects people with type 1 diabetes. Ketosis in and of itself isn’t thought to be harmful.
A ketogenic diet is believed to be safe for many people, including for significantly overweight or obese individuals.
This low-carb, high-fat diet is similar to Atkins. You replace your carb intake with a high amount of fat. Your body, when in ketosis, is very efficient at burning fat. Your body also turns fat into ketone bodies in your liver. Those ketones can supply your brain with energy.
Some things to know about ketosis include:
- When you’re in ketosis, your body uses fat for its fuel rather than carbs as it is in normal diets.
- When you significantly limit carb intake, you’re limiting your body’s supply of glucose, which is your primary source of cellular energy otherwise.
- Following a keto diet is the most effective and efficient way to get into ketosis.
- You usually limit your carbs to 20 to 50 grams a day to get into ketosis.
- You’ll have a lot of healthy fats, including meat, fish, nuts, olive oil, and eggs.
- Your protein intake should only be moderate because protein can convert to glucose in high amounts. That conversion can slow down your transition to a state of ketosis.
- Some people combine intermittent fasting with a keto diet because it can help them get into ketosis faster.
- Ultimately, you want to ensure you’re getting more of your calories from fat than carbs.

What Are the Benefits of Keto Dieting?
Researchers believe there are a lot of potential benefits of keto dieting.
Weight Loss
Whether or not weight loss is sustainable is debated, but it’s pretty undeniable that following a ketogenic diet can help you lose initial weight. Some people lose significant amounts of weight on the diet.
The diet can help improve your metabolism and reduce your appetite. The foods you eat on the diet might reduce hormones that stimulate hunger.
You can lose weight without tracking your food intake or counting your calories, so that’s certainly an upside in the eyes of many people.
In one study of 34 older adults, the participants following a ketogenic way of eating for eight weeks lost almost five times as much total body fat as participants following a low-fat diet.
Diabetes and Prediabetes
When you follow a high-fat, low-carb diet, it can impact how your body uses and stores energy in a beneficial way for people with diabetes and prediabetes.
When you’re keto dieting, your body will convert fat rather than sugar into the source of energy you use. This way of eating might improve your blood glucose levels and reduce the need for insulin.
Whether you’re following a keto way of eating or not, it’s often recommended that you manage carbohydrate intake when you have type 2 diabetes. Carbs turn to sugar, and when you consume large amounts of them, cause your blood sugar to spike.
In one study, a ketogenic diet improved insulin sensitivity by 75%.
In a small study of females with type 2 diabetes, following a ketogenic diet for 90 days reduced levels of hemoglobin A1C. Hemoglobin A1C is a measure of long-term blood sugar management.
Another study of nearly 350 people with type 2 diabetes found individuals following a keto diet lost an average of more than 26 pounds over two years.
Other Benefits of Keto Dieting
Some of the other benefits that come with this type of eating include:
- Your appetite may be automatically reduced. Studies show when you reduce your carb intake and eat more fat and protein, you’re going to consume fewer calories.
- You can lose weight relatively quickly when you follow a low-carb diet. For example, studies that compare low-fat and low-carb diets find carbohydrate restriction can lead to weight loss two to three times greater than following a diet low in fat, especially in the first few weeks or months. Quick weight loss can help you get on track with your overall health and fitness goals.
- Many people struggle with abdominal fat. How your body stores fat can increase your risk of chronic diseases, affecting your health. There are two main types of fat—subcutaneous and visceral. Subcutaneous means the fat is under your skin. Visceral fat accumulates in your abdomen and lodges around your organs. Having too much visceral fat is associated with inflammation and insulin resistance and is one of the primary drivers of metabolic dysfunction. Low-carb diets are very effective at helping with the loss of visceral abdominal fat.
- Ketogenic diets can significantly reduce triglycerides. Triglycerides are fat molecules circulating in your blood. According to human studies, a primary driver of high triglycerides is carb consumption.
- Having high blood pressure puts you at risk for many diseases such as renal disease or kidney failure, stroke, and heart disease. Following a ketogenic or low-carb diet may reduce your blood pressure.
- Metabolic syndrome is a condition highly linked to the risk of diabetes and cardiovascular disease. Metabolic syndrome is a collection of symptoms. These symptoms include high blood pressure and elevated fasting blood sugar levels. Other symptoms of metabolic syndrome are abdominal weight gain and obesity, high triglycerides, and low HDL levels. HDL is considered “good” cholesterol. Following a keto style of eating is effective at treating all of the symptoms of metabolic syndrome.
- Following this type of diet can significantly lower the risk of heart disease, a major killer in the U.S.
- A keto diet may be helpful for many brain disorders. Your brain requires glucose because some parts burn only this type of sugar. If you don’t eat any carbs, your liver will produce glucose from protein to fuel your brain. Your brain can also burn ketones. Ketones are formed when your carb intake is very low. For many years, the ketogenic diet has been used to treat seizures in children with epilepsy who don’t respond to medication because of the effects of ketone formation on brain health. Currently, ketogenic diets are also being studied for their benefits on other brain conditions like Parkinson’s and Alzheimer’s and drug-resistant epilepsy in children. The extensive history of the keto diet shows it is more than a fad diet, despite its current popularity.
- Following low-carb and ketogenic diets is being looked at to help treat cancer because it may help slow the growth of certain types of tumors.
- Research suggests keto diets could improve the outcomes of certain types of traumatic brain injuries.
- Since ketogenic diets reduce insulin levels, it may be a helpful option for the treatment of polycystic ovary syndrome (PCOS).

Is Keto Dieting Safe?
Back to our original question—is keto dieting safe? The keto diet is mostly safe, but with some exceptions and things to know. First, this is not a replacement for medical advice from a professional. Talk to your doctor if you’re thinking about making a major change to how you eat, such as going keto.
There are often initial side effects when you begin the popular diet, known as the keto flu. The keto flu should end within the first few days after your body adjusts to this way of eating, increasing fat intake and limiting the total grams of carbs you can have.
Symptoms of keto flu can include:
- Constipation
- Nausea
- Diarrhea
- Sleep problems
- Digestive discomfort
- Poor energy levels
- Mood swings
- Reduced mental function
To minimize keto flu symptoms, you should make sure that you’re adding salt to your meals or taking a mineral supplement. Ketogenic dieting can affect your water and mineral balance, which is why salt can be helpful.
Other potential risks and rare adverse side effects of the keto diet can include:
- Low levels of protein in the blood
- Extra fat in the liver
- Kidney stones
- Deficiencies of micronutrients
The above aren’t necessarily the risks of doing the keto diet short or moderate term. These risks are typically only when you follow a keto diet in the long term. Currently, there is a lot of research being done to assess the safety of the keto diet in the long term.
Who Shouldn’t Follow a Keto Diet?
Some of the people that shouldn’t try to do a keto diet include:
- Pregnant women—it’s already challenging to make sure you’re getting all the nutrients required during pregnancy. Following a keto diet could mean that you and your baby aren’t getting enough of what you need. You need a variety of healthy foods, including fresh fruits, leafy greens, and other items that you might have to limit on a keto diet.
- Breastfeeding women—When you’re breastfeeding, you need even more calories than pregnant. If you put yourself on a restrictive diet, you may not be getting enough calories or fruits and vegetables.
- People with disordered eating—The keto diet can feel extreme, triggering disordered eating patterns if you have a history of them.
- Individuals with kidney disease or pancreatitis.
- People who take a sodium-glucose cotransporter 2 (SGLT2) for diabetes—This medication can increase the risk of diabetic ketoacidosis.
- If you have diabetes, you should carefully monitor your blood sugar when starting a keto diet. You also need to monitor your ketone levels.

Key Takeaways—Is Keto Dieting Safe?
Overall, keto dieting is considered safe for most people, particularly in the short-term meaning for two years or less. Ketogenic diets may have benefits for a number of health conditions and may help with weight loss. According to Harvard Medical School and other organizations, we don’t know as much about the long-term effects as we need to, but research is ongoing.
There are a few situations where keto dieting might not be safe, but these are rare.
If you’re wondering if keto dieting is safe, the best thing you can do is talk to your health care professional. Tell them about any health conditions you have and medications you take, and they can help you determine if a keto diet is safe or would be a good option in your situation.
Your doctor might recommend a more balanced diet plan in your situation or a less restrictive version of a low-carbohydrate diet that can still have beneficial effects.
Peer-Reviewed Research and References On The Topic of “Is Keto Dieting Safe”
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7425171/
https://pubmed.ncbi.nlm.nih.gov/15767618/
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4259868/
https://pubmed.ncbi.nlm.nih.gov/17228046/
https://pubmed.ncbi.nlm.nih.gov/15533250/
https://nutritionandmetabolism.biomedcentral.com/articles/10.1186/1743-7075-2-31
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5842847/
https://pubmed.ncbi.nlm.nih.gov/31185843/