Currently, there are clinical trials reviewing the use of Ketogenic Diet in treating diabetes, cancer, obesity, autism, migraine, amyotrophic lateral sclerosis (ALS), Alzheimer’s and other medical conditions.
Long-Term Side Effects of following a Ketogenic Diet
*Acute pancreatitis
*Cardiomyopathy
*Gallstones
*Thyroid dysfunction
*Hypoproteinemia
*Hepatitis
*Hypocalcemia and bone damage
*Disruptions in lipid metabolism
*Nephrolithiasis & Urolithiasis
Contraindications for Ketogenic Diets
*48 hrs prior to any type of surgery due to fluid/electrolyte balance, blood glucose, blood pressure, that might complicate surgical procedures.
*Hypertriglyceridemia-associated acute pancreatitis.
*Pregnancy and breastfeeding.
*Kidney failure.
*Moderate-Severe Chronic Kidney Disease.
*Liver failure.
*Respiratory failure.
*Cardiac Condition such as unstable angina, recent stroke or heart attack in the past 12 months, arrhythmia, heart failure.
*Mental health Issues including eating disorders, severe mental illnesses, alcohol and substance abuse.
*Active or severe infections.
*Frail elderly individuals.
*Severe hypertriglyceridemia, inherited causes of severe dyslipidemia, hyperchylomicronemia.
*Individuals with rare disorders such as Porphyria.
*Metabolic conditions.
*Type I Diabetes Mellitus.
*Renal stones.
*Severe dyslipidemia (high level of lipids  -cholesterol, triglycerides, or both, or a low high-density lipoprotein (HDL) cholesterol level).
*Significant liver disease (other than liver failure which is an absolute contraindication).
 *Severe gastroesophageal reflux (acid reflux).
 *Individuals with poor oral intake.
 *Cardiomyopathy.
 *Chronic metabolic acidosis.
Current Indications for Ketogenic Diets:
*Epilepsy
*Severe Obesity (including management of obesity pre-bariatric surgery) 
*Sarcopenic Obesity
*Obesity-Associated T2DM (preserved beta cell function) Obesity-Associated *Hypertriglyceridemia
*Obesity-Associated Hypertension
Currently, the long-term safety of Ketogenic Diet is unknown.