Special diets for type 2 diabetes often focus on weight loss, so it might seem crazy that a high-fat diet is an option. But the ketogenic (keto) diet, high in fat and low in carbs, can potentially change the way your body stores and uses energy, easing diabetes symptoms.
With the keto diet, your body converts fat, instead of sugar, into energy. The diet was created in 1924 as a treatment for epilepsy, but the effects of this eating pattern are also being studied for type 2 diabetes. The ketogenic diet may improve blood glucose (sugar) levels while also reducing the need for insulin. However, the diet does come with risks, so make sure to discuss it with your doctor before making drastic dietary changes.
Many people with type 2 diabetes are overweight, so a high-fat diet can seem unhelpful. The goal of the ketogenic diet is to have the body use fat for energy instead of carbohydrates or glucose. A person on the keto diet gets most of their energy from fat, with very little of the diet coming from carbohydrates.
The ketogenic diet doesn’t mean you should load up on saturated fats, though. Heart-healthy fats are the key to sustaining overall health. Some healthy foods that are commonly eaten in the ketogenic diet include:
- fish such as salmon
- cottage cheese
- olives and olive oil
- nuts and nut butters
The ketogenic diet has the potential to decrease blood glucose levels. Managing carbohydrate intake is often recommended for people with type 2 diabetes because carbohydrates turn to sugar and, in large quantities, can cause blood sugar spikes. If you already have high blood glucose, then eating too many carbs can be dangerous. By switching the focus to fat, some people experience reduced blood sugar.
The Atkins diet is one of the most famous low-carb, high-protein diets that is often associated with the keto diet. However, the two diets have some major differences. The Atkins diet was created in the 1970s by Dr. Robert C. Atkins. It’s often promoted as a way to lose weight that also controls numerous health issues, including type 2 diabetes.
While cutting excess carbs is a healthy step, it’s not clear if this diet alone can help diabetes. Weight loss of any kind is beneficial for diabetes and high blood sugar levels, whether it’s from the Atkins diet or another program.
Unlike the keto diet, the Atkins diet doesn’t necessarily advocate increased fat consumption. Still, you might increase your fat intake by limiting carbohydrates and eating more animal protein. The potential drawbacks are similar. Aside from a high saturated fat intake, there is the possibility of low blood sugar, or hypoglycemia, from restricting carbs too much. This is especially true if you take medications that increase insulin levels in the body and don’t change your dosage. Cutting carbs on the Atkins diet can potentially aid weight loss and help you control diabetes symptoms, but there aren’t enough studies to suggest that Atkins and diabetes control go hand-in-hand.
Changing your body’s primary energy source from carbohydrates to fat causes an increase in ketones in the blood. This “dietary ketosis” is different from ketoacidosis, which is an extremely dangerous condition. When you have too many ketones, you may be at risk for developing diabetic ketoacidosis (DKA). DKA is most prevalent in type 1 diabetes when blood glucose is too high and can arise from a lack of insulin. Although rare, DKA is a possibility in type 2 diabetes if ketones are too high. Being ill while on a low-carb diet may also increase your risk for DKA.
If you’re on the ketogenic diet, be sure to test blood sugar levels throughout the day to make sure they are within their target range. Also, consider testing ketone levels to make sure you’re not at risk for DKA. The American Diabetes Association recommends testing for ketones if your blood sugar is higher than 240 mg/dL. You can test at home with urine strips.
DKA is a medical emergency. If you’re experiencing the symptoms of DKA, see your doctor immediately. Complications can cause diabetic coma.
The warning signs of DKA include:
- consistently high blood sugar
- dry mouth
- frequent urination
- breath that has a fruit-like odor
- breathing difficulties
The ketogenic diet seems straightforward. Unlike a typical low-calorie diet, however, a high-fat diet requires careful monitoring. In fact, you may start the diet in a hospital. Your doctor needs to monitor both blood glucose and ketone levels to make sure that the diet isn’t causing any adverse effects. Once your body adjusts to the diet, you may still need to see your doctor once or twice a month for testing and medication adjustments.
Even if your symptoms improve, it’s still important to keep up with regular blood glucose monitoring. For type 2 diabetes, testing frequency varies. Be sure to check with your doctor and determine the best testing schedule for your situation.
In 2008, researchers conducted a 24-week study to determine the effects of a low-carbohydrate diet on people with type 2 diabetes and obesity. At the end of the study, participants who followed the ketogenic diet saw greater improvements in glycemic control and medication reduction compared to those who followed a low-glycemic diet. A study from 2017 found the ketogenic diet outperformed a conventional, low-fat diabetes diet over 32 weeks in regards to weight loss and A1c. A 2013 review reports again that a ketogenic diet can lead to more significant improvements in blood sugar control, A1c, weight loss, and discontinued insulin requirements than other diets.
There is research that supports the ketogenic diet for diabetes management, while other research seems to recommend opposing dietary treatments like a plant-based diet. Research from 2017 confirms that people with diabetes who followed a plant-based diet experienced significant improvements in blood sugars and A1c, cardiovascular disease risk factors, gut bacteria that is responsible for insulin sensitivity, and inflammatory markers like c-reactive protein.
The ketogenic diet may offer hope to people with type 2 diabetes who have difficulty controlling their symptoms. Not only do many people feel better with fewer diabetic symptoms, but they may also be less dependent on medications. Still, not everyone has success on this diet. Some may find the restrictions too difficult to follow over the long term. Yo-yo dieting can be dangerous for diabetes, so you should only start the ketogenic diet if you’re sure you can commit to it. A plant-based diet may be more beneficial for you both short- and long-term, so input from your dietitian and doctor can help guide your diet choice.
While you may be tempted to self-treat with a more “natural” route through dietary changes, be sure to discuss the keto diet with your doctor first. The diet may throw off your blood sugar levels, causing further issues, especially if you are on medications for diabetes.