What’s the Difference Between Ketosis and Diabetic Ketoacidosis?

Ketosis and ketoacidosis may sound similar, but ketosis is a fat-burning metabolic state, while diabetic ketoacidosis is a life-threatening complication of diabetes.

Here's everything you need to know about ketosis versus ketoacidosis.

"Ketosis is the state when the body shifts from using carbs as the primary source of energy to burning fat," says Vandana Sheth, RDN, an award-winning dietitian and diabetes care and education specialist based in Los Angeles. "This happens when carb intake is significantly reduced, which causes the liver to produce ketones from fat stores."

To understand ketosis, it helps to first look at how the body burns energy. Carbohydrates and fat are both energy sources, and the body typically burns carbs (glucose) first, then fat. If there aren’t enough carbohydrates in your system, it begins to break down fat for energy, which puts your body into a state of ketosis.

“The keto diet is a high-fat, moderate-protein, low-carb diet. The macronutrient breakdown on a ketogenic diet may look like 60 to 80 percent of your total daily calories from fat, 10 to 15 percent of your total daily calories from protein, and less than 10 percent of your total daily calories from carbs,” Sheth says.

"This macronutrient breakdown is essential for achieving and maintaining ketosis, during which the body effectively uses fat for energy," Sheth says. And it usually involves cutting out most sources of carbs — even healthy ones like fruit, starchy vegetables, and grains.

• Improved blood sugar
• Weight loss
• Reduced appetite
• More energy
• Better mental clarity

Diabetes-related ketoacidosis, or diabetic ketoacidosis (DKA), is a serious diabetes-related condition triggered by severe insulin deficiency. As levels of the hormone glucagon rise to break down fats and proteins to make ketones — an alternative energy source for the brain — it can lead to dangerously high levels of ketones in the blood when insulin levels are insufficient.

"Since the body isn't producing insulin, our cells don't get the glucose they need for energy," says Simran Malhotra, MD, founder of Wellness by Lifestyle MD in Bethesda, Maryland, and a medical reviewer for Everyday Health. "This process can lead to an imbalance of key hormones and rapid breakdown of fat, which can lead to excessive ketone production and acid buildup in the bloodstream.”

The main cause of ketoacidosis is not having enough insulin in your system, whether it's because of a new diabetes diagnosis or poor diabetes management. But ketoacidosis can also be caused by an infection (such as pneumonia or a urinary tract infection), drug or alcohol use disorders, or a medication that affects how your body uses sugar.

For example, corticosteroids, which are used for Crohn’s disease and asthma, among other health conditions, can make it harder for your cells to use insulin; diuretics, used for controlling heart disease, can increase blood glucose levels.

• Excessive thirst
• Intense hunger
• High blood glucose (over 250 mg/dL)
• Frequent urination
• Vomiting
• Weakness
• Abdominal pain
• Shortness of breath
• Fruity-smelling breath
• Confusion
• Potential for coma or death

The key differences between ketosis and DKA are their causes and effects on the body. Ketosis is caused by depleting the body’s glucose supplies, either by fasting (even overnight) or by following a low-carb diet. DKA is caused by severe insulin deficiency due to uncontrolled diabetes.

DKA’s effects on the body are much more serious and can be fatal. “This process can lead to an imbalance of key hormones and rapid breakdown of fat, which can lead to excessive ketone production and acid buildup in the bloodstream," Malhotra says.

Both ketosis and ketoacidosis come with side effects, but unlike ketosis, DKA is associated with severe symptoms, requiring immediate medical intervention.

• Bad breath (keto breath)
• Constipation, due to low fiber intake
• Dehydration
• Low bone density and bone fractures
• High cholesterol
• Insomnia
• Kidney stones

• Nausea
• Abdominal pain
• Vomiting
• Sped-up breathing
• Fruity-smelling breath
• Extreme fatigue
• Confusion
• Reduced alertness
• Losing consciousness

"DKA is often triggered by a stressful event, such as an infection or failure to take the appropriate medications,” Malhotra says. “It is important for people to be mindful of this so they understand that it could precipitate an event. If you notice early symptoms of DKA, it is important to hydrate, monitor your blood sugar levels, and talk to your medical provider to address the precipitating cause."

The ketogenic diet isn't right for everyone. People who are pregnant, breastfeeding, or about to undergo surgery shouldn't try the keto diet. People with chronic health conditions, especially those with liver, kidney, and respiratory failure, should check with their doctor before starting a keto diet.

If you're cleared to do keto, you'll start off by cutting out most carbs and eating a diet that's high in fat and moderate in protein. Most people can achieve a state of ketosis within two to seven days of following a low-carb diet. However, the exact timing varies based on individual factors such as physical activity, metabolism, and previous food habits, Sheth says.

“Some of the signs of being in ketosis include reduced appetite, mild fatigue, and flu-like symptoms (keto flu), but these often subside,” Sheth says.

Is Ketosis Safe for People With Diabetes?

The ketogenic diet can be a safe option for those with type 1 or type 2 diabetes — but only under careful management. "Anyone considering a keto approach with diabetes should consult with their healthcare team, especially a dietitian, to discuss food choices, concerns, and safety, including medication adjustments, especially insulin, to prevent hypoglycemia and to ensure stable blood sugar levels," Sheth says.

While the ketogenic diet may provide benefits for those managing diabetes, it's important to follow it with professional guidance. You'll need to actively monitor your ketone levels while on the diet using urine ketone strips, breath analyzers, or blood ketone meters. "Monitoring for ketones regularly is very important — especially when blood sugar levels are high — to reduce the risk of DKA," Sheth says.

• Whereas ketosis can occur from eating a low-carb or keto diet and isn’t harmful, ketoacidosis is a life-threatening complication of diabetes that can cause a dangerous level of acid in the blood.
• During ketosis, a fat-burning metabolic state, ketones are present in your blood, but not at levels high enough to make your blood acidic, because most people make enough insulin to suppress acidosis.
• If you notice symptoms of DKA, like rapid and deep breathing, confusion, nausea, or vomiting, seek medical attention immediately, as DKA can lead to coma or death.