Some research suggests a ketogenic (keto) diet may benefit some people with type 2 diabetes. This high fat, moderate protein, very low carbohydrate diet may help with managing blood sugar. However, long-term studies are lacking.

While some researchers indicate the keto diet might help individuals with type 2 diabetes, the American Diabetes Association (ADA) does not recommend one diet over another.

Everyone has different dietary needs. Healthcare professionals and registered dietitians now individualize diet plans based on a person’s eating habits, preferences, target weight, and target blood sugar levels.

In this article, we look at whether the keto diet works for managing type 2 diabetes.

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Limiting carbohydrates is the central concept of the keto diet.

Carbohydrate-rich foods can raise a person’s insulin levels. Typically, the carbohydrate intake on a keto diet ranges from 20 to 50 grams (g)Trusted Source per day for a 2,000-calorie diet.

To follow the keto diet, people might consider developing a diet plan where they get 10% of their calories from carbohydrates, 20% from protein, and 70% from fat. However, there are different versions of the diet, and macronutrient proportions vary depending on the type.

A keto diet may consist of the following types of food:

  • Low carb vegetables: These include leafy greens and broccoli.
  • Eggs: Eggs are low in carbohydrates and an excellent source of protein.
  • Meats: The keto diet allows for eating poultry, beef, and pork, which are rich in high quality protein.
  • Healthy fat sources: These include avocados, olive oil, nuts, and seeds.
  • Fish and shellfish: These are sources of protein.
  • Dairy: Unsweetened dairy products are acceptable in a keto diet.
  • Berries: These are sources of fiber, vitamins, minerals, and antioxidants and okay to consume on the keto diet in certain quantities.

Researchers initially developed and continue to recommend the keto diet for children with epilepsy. However, some recent research reviews maintain that it might benefitTrusted Source some people with diabetes.

The keto diet severely restricts carbohydrates, forcing the body to break down fats for energy. Ketosis is the process of using fat for energy. This process produces a fuel source called ketones.

Foods containing carbohydrates, such as bread, rice, pasta, milk, and fruit, are the main fuel for many bodily processes. The body uses insulin to help bring glucose (blood sugar) from the blood into the cells for energy.

However, with diabetes, insulin is either absent or does not work properly. This disrupts the body’s ability to use carbohydrates effectively, and in turn, causes high sugar levels in the blood.

Eating a high carb meal could lead to a rise in blood sugar, especially in someone with diabetes. Diet is important for managing both type 1 and type 2 diabetes.

Scientists have lookedTrusted Source into the main motivations that people with type 2 diabetes have for starting a keto diet. The key motivations include:

  • improving blood sugar management
  • stopping or reducing diabetes medications
  • losing weight
  • reversing diabetes

A keto diet could help some people with type 2 diabetes because it allows the body to maintain blood sugar levels at a low but healthy level.

The diet’s lower intake of carbohydrates may help minimize large fluctuations in blood sugar, which could positively affect several clinical markers of blood sugar control.

However, a 2022 reviewTrusted Source of randomized clinical trials found little evidence to support the effectiveness of keto diets for the long-term management of type 2 diabetes.

Researchers noted that while some studies suggest low carb diets could improve glycemic control and aid weight loss, studies typically only lasted 6 to 12 months. Overall, dropout rates in the keto diet groups were as high as 54%.

A 2022 studyTrusted Source compared the effects of a keto diet with those of a Mediterranean diet in 33 people with type 2 diabetes over 12 months. The study’s authors found that HbA1c values, an important component of type 2 diabetes management, did not differ between the diets, despite both diets improving HbA1c values throughout the study.

HbA1c is a clinical measure of blood sugar control that tests the amount of blood sugar traveling with hemoglobin in the blood over about 3 months.

For the reasons above, experts caution against the idea that there is a keto diet advantage for managing type 2 diabetes over other common dietary strategies, especially over the long term.

Scientists continue to study the effects of a keto diet on people with type 2 diabetes, including the underlying mechanisms that may explain the potential benefits.

There are certain groups of people who should not follow a keto diet, including people who:

  • are pregnant or lactating
  • take certain medications, such as SGLT-2 inhibitors
  • have any of the following conditions:
    • a history or current diagnosis of an eating disorder
    • kidney disease
    • pancreatitis
    • liver failure
    • disorders of fat metabolism

In some people, the keto diet could potentially lead to various benefits, including:

  • weight loss, if a person could benefit from losing weight
  • a reduced dependency on antidiabetic medication
  • lower blood pressure
  • improved insulin sensitivity
  • increased levels of high-density lipoprotein (HDL) cholesterol, without increasing low-density lipoprotein (LDL) cholesterol
  • reduction in triglycerides
  • improved quality of life

As keto diets may help reduce blood sugar levels and weight, if needed, people with type 2 diabetes who follow a keto diet may be able to reduce their need to take antidiabetic medication.

A 2022 meta-analysisTrusted Source found that people with type 2 diabetes who followed a keto diet reduced their need to take antidiabetic medication compared with people who used other dietary treatments, but only for up to 12 months.

People may find the keto diet hard to maintain long term. As people add carbohydrates back to their diet, they may need to increase their diabetes medication.

However, experts warnTrusted Source that those following the keto diet alongside an insulin regimen might have a higher risk of developing hypoglycemia (low blood sugar).

Hypoglycemia occurs when blood sugar levels fall below 70 milligrams per deciliter (mg/dl).

It is important to consult with a healthcare professional before starting a keto diet.

The keto diet helps the body burn fat, which is beneficial when a person is trying to reach or maintain a moderate weight for their body type. This kind of diet may be helpful for people who are currently carrying excess weight, which has influenced the development of prediabetes or type 2 diabetes.

Recent studiesTrusted Source suggest that people with type 2 diabetes and obesity undertaking a keto diet may lose more weight than people who use other diet strategies for up to 6 months.

However, the restrictive nature of the keto diet can make it difficult to follow for a long time. People typically find it more beneficial to follow a more moderate diet and a lifestyle program that is sustainable long term.

Light to moderate but sustained weight loss through diet and exercise might support glycemic control in people who have type 2 diabetes, according to a 2023 study.

The keto diet may be one possible blood sugar management option for some people with type 2 diabetes.

However, as the keto diet involves a shift in typical eating habits and the body switching to a different energy source, it might lead to some adverse effectsTrusted Source.

Short-term side effects

Following the keto diet could result in short-term side effects, including:

In most instances, the side effects are temporary, lasting a few days to a few weeks.

Long-term effects of a keto diet might includeTrusted Source the development of kidney stones and an increased risk of nutrient deficiencies due to the restriction or exclusion of certain food groups.

Other complications might include:

Some researchers have suggested that since a keto diet often involves additional fat, there might be a higher riskTrusted Source of cardiovascular disease (CVD) due to a buildup of fats in the arteries.

People with diabetes already have an increased riskTrusted Source of CVD. However, the scientific evidence is conflicting on the risk of CVD in people with type 2 diabetes following a keto diet.

There is a lack of evidence about the long-term safety and effectiveness of the keto diet, and healthcare professionals have called for more primary studies and evidence before recommending this diet for people with type 2 diabetes.

Ketosis is the desired state of the body using fat instead of carbohydrates for fuel as part of the keto diet. In ketosis, the liver has broken down enough fat to produce ketones that circulate freely in the bloodstream.

Ketosis is a metabolic process that doctors generally consider safe for most people with proper management. Ketosis is not a medical condition.

Ketoacidosis is a potentially life threatening medical complication. The body essentially believes it is starving and rapidly breaks down fat into ketones. When ketones become dangerously high, the blood can become more acidic.

Ketoacidosis is a complication of type 1 diabetes, but it can also occur in people with unmanaged diabetes and people with alcoholism.

There have been some reports of ketoacidosis occurring in people with type 2 diabetes who followed a keto diet with prolonged periods of fasting.

If symptoms of ketoacidosis appear, seek medical attention immediately.

Experts do not currently recommend the keto diet for type 2 diabetes management. Although a keto diet may provide benefits for some people with type 2 diabetes, it comes with some risks, and people should not try it without speaking with their doctor first.

When it comes to managing diabetes, there is no one right diet. The key is following an eating plan that meets a person’s personal preferences and needs and helps them maintain their clinical health targets, such as blood sugar levels or weight.

The keto diet is highly restrictive, which means it can be hard to follow in the long term. Experts do not recommend following this diet for longer than 12 months.

To fully assess the benefits of the keto diet for type 2 diabetes, scientists suggest that benefits need to be present over 12 monthsTrusted Source or longer. For this reason, additional long-term studies of the keto diet in larger samples of more diverse participants are necessary.

A person should always speak with a doctor or dietitian before making significant changes to their diet, including when considering trying a keto diet.

Health authorities in the United States do not recommend the keto diet to manage type 2 diabetes. It may be best for people with this condition to focus on:

  • following a healthy, balanced diet with plenty of fresh fruits and vegetables
  • spreading out their intake of carbohydrates evenly throughout the day
  • eating smaller meals more often rather than a large meal once per day

A healthcare professional can help individuals with type 2 diabetes choose the plan that best fits their lifestyle.