Who shouldn't be on the keto diet? Understanding the medical contraindications

October 19, 2025 •

4 min read

According to a review of scientific literature, the ketogenic diet is contraindicated in individuals with specific medical conditions such as liver failure and chronic kidney disease. This article explains who shouldn't be on the keto diet and why a low-carb, high-fat diet could be harmful for certain populations.

Quick Summary

Individuals with certain medical conditions, including liver, pancreatic, and kidney issues, should avoid the keto diet due to serious health risks. It is also unsafe for pregnant women, those with a history of eating disorders, and some diabetes patients.

Key Points

Pre-existing Medical Conditions: Individuals with liver failure, pancreatitis, or gallbladder disease should not attempt the keto diet due to the high fat content straining these organs.
Kidney Compromise: Those with chronic kidney disease (CKD) face an increased risk of complications, including exacerbated kidney damage and kidney stones, on the keto diet.
Diabetes Management: The diet poses serious risks, such as diabetic ketoacidosis (DKA) and hypoglycemia, for people with type 1 diabetes or those using SGLT-2 inhibitors.
Vulnerable Populations: Pregnant and breastfeeding women, children, and underweight individuals should avoid the keto diet, as it restricts essential nutrients vital for growth and development.
History of Eating Disorders: The restrictive nature of the keto diet can trigger or worsen disordered eating behaviors in individuals with a history of such issues.
Rare Metabolic Disorders: Genetic conditions that impair fat metabolism make the keto diet exceptionally dangerous, as the body cannot properly utilize fat for energy.
Professional Guidance is Key: Due to the wide range of potential risks and complications, medical supervision is essential before starting the keto diet, especially if any health concerns are present.

Medical Conditions That Exclude the Keto Diet

The ketogenic diet, with its drastic reduction in carbohydrate intake, forces the body into a state of ketosis, where it burns fat for fuel instead of glucose. While some people experience success with this diet, for others, it can be extremely dangerous. The high fat content and metabolic shifts required for ketosis can exacerbate or create new health problems in people with certain pre-existing conditions.

Liver and Pancreatic Conditions

The liver and pancreas are crucial for metabolism and digestion. The keto diet's high-fat load puts extra strain on these organs, making it unsafe for those with compromised function.

Liver Failure or Conditions: The liver is responsible for producing ketone bodies from fat. In cases of liver failure or severe liver disease, this process is impaired, and the additional fat intake can be harmful.
Pancreatitis: Inflammation of the pancreas can be worsened by a high-fat diet, as the pancreas produces enzymes necessary to digest fats. A ketogenic diet can place an excessive burden on this organ.
Gallbladder Disease: The gallbladder stores bile, which helps break down dietary fats. Increased fat intake stimulates bile release, which can trigger painful symptoms or blockages in individuals with gallstones or a history of gallbladder problems.

Kidney Health and Function

The kidneys play a vital role in filtering waste products from the blood. The keto diet can put undue stress on them, especially in the long term.

Chronic Kidney Disease (CKD): For people with already weakened kidneys, the potential for increased protein intake and metabolic changes can be risky. Some studies suggest that the increased acidity from ketosis could worsen CKD progression.
Kidney Stones: The keto diet can cause changes in urine composition, such as decreased citrate levels and increased calcium, raising the risk of kidney stone formation.

Diabetes and Blood Sugar Management

While the keto diet is sometimes explored for type 2 diabetes management, it carries significant risks, particularly for those on medication.

Type 1 Diabetes (T1D): People with T1D are at a heightened risk of developing diabetic ketoacidosis (DKA), a life-threatening condition where high levels of ketones make the blood dangerously acidic. DKA is distinct from nutritional ketosis and is a medical emergency.
Use of SGLT-2 Inhibitors: Patients with type 2 diabetes taking sodium-glucose cotransporter 2 (SGLT-2) inhibitors must avoid the keto diet, as the combination dramatically increases the risk of a dangerous condition called euglycemic DKA.
Hypoglycemia Risk: Individuals with diabetes on insulin or other hypoglycemic agents are at risk of severe low blood sugar episodes if their medication is not expertly managed alongside a low-carb diet.

Special Populations and Conditions

Some groups have unique physiological needs or psychological factors that make the keto diet inappropriate.

Pregnancy and Breastfeeding: A balanced diet rich in micronutrients is essential during pregnancy and breastfeeding. The restrictive nature of the keto diet can lead to nutrient deficiencies and potential risks for both mother and child.
Children and Adolescents: Growing bodies require a wide range of nutrients from all food groups. Restrictive diets can hinder proper development and increase the risk of developing eating disorders later in life.
History of Eating Disorders: The rigid rules and extreme food restrictions of the keto diet can trigger or worsen disordered eating behaviors, such as orthorexia or binge-restrict cycles, in individuals with a history of eating disorders.
Rare Metabolic Disorders: Inherited disorders affecting fat metabolism, such as carnitine deficiency or pyruvate carboxylase deficiency, are absolute contraindications for the keto diet. Attempting ketosis can lead to severe health crises in these individuals.

Potential Risks vs. Medical Contraindications


Condition / Factor	Keto Diet Potential Impact	Medical Supervision Required	Who Should Avoid Keto	Who May Consider (with caution)
Liver Disease	Exacerbated liver damage, impaired ketosis	Yes, mandatory	Severe liver disease, liver failure	Non-alcoholic fatty liver disease (with professional guidance)
Chronic Kidney Disease	Increased kidney stress, worsened progression	Yes, mandatory	Advanced CKD, compromised kidney function	Mild CKD (only with nephrologist supervision)
Diabetes (Type 1 or SGLT-2 use)	High risk of DKA and hypoglycemia	Yes, mandatory	Type 1 Diabetes, taking SGLT-2 inhibitors	Select Type 2 diabetes patients (with close medical monitoring)
Gallbladder Issues	Bile overproduction, gallstone pain	Yes, strongly advised	History of gallstones, diseased gallbladder	Individuals post-cholecystectomy (with doctor's approval)
Eating Disorder History	Triggers relapse of restrictive behaviors	Yes, strongly advised	All individuals with a history of eating disorders	None
Weight Status	Unnecessary restriction, malnutrition risk	Advisable	Underweight individuals	Overweight/obese individuals (with medical advice)
Pregnancy / Breastfeeding	Inadequate nutrition for mother and child	Yes, mandatory	All pregnant and breastfeeding women	None
Rare Metabolic Disorders	Dangerous metabolic crisis	Yes, mandatory	Confirmed diagnosis of rare metabolic disorders	None

Conclusion: Always Consult a Professional

While the ketogenic diet has been shown to be effective for certain medical applications, such as controlling epilepsy, and has been adopted for weight loss, it is not a suitable option for everyone. The potential for severe, adverse health outcomes in specific populations is significant and well-documented. Attempting such a restrictive dietary change without a thorough understanding of the risks, especially when underlying health issues are present, can be extremely dangerous. Anyone considering a keto diet should consult with a doctor or registered dietitian to determine if it is appropriate and safe for their individual health profile. This professional guidance ensures a personalized approach that prioritizes long-term well-being over short-term trends. For a comprehensive overview of potential contraindications, review this scientific evidence regarding the ketogenic diet: https://pmc.ncbi.nlm.nih.gov/articles/PMC7539910/.

Frequently Asked Questions

Yes, but with caution. Since your gallbladder stored bile to digest fat, its removal can make it harder to handle high-fat meals. It is important to consult a doctor to ensure a smooth transition and manage any potential digestive issues that arise from a high-fat diet.

The keto diet is unsafe for type 1 diabetes patients due to a high risk of developing diabetic ketoacidosis (DKA), a dangerous medical emergency. It can also cause severe hypoglycemia if insulin dosage is not carefully managed.

For those with liver failure or disease, the keto diet places a significant burden on the liver, which is already impaired. The liver's inability to process high amounts of fat efficiently can worsen the condition.

No, the keto diet is not recommended for pregnant or breastfeeding women. These stages require a wide variety of nutrients for both maternal health and infant development, which can be restricted in a high-fat, low-carb diet.

Yes, the rigid and restrictive nature of the ketogenic diet can trigger a relapse of disordered eating patterns and an unhealthy fixation on food and weight.

Yes. A critical conflict exists for individuals with type 2 diabetes who are taking SGLT-2 inhibitor medications, as this combination significantly increases the risk of euglycemic diabetic ketoacidosis.

Restrictive diets like keto can negatively impact a child's growth and development by limiting important nutrients found in fruits, vegetables, and whole grains. It may also increase their risk of developing eating disorders later.