Health Risks of the Ketogenic Diet

They are many potential benefits to the ketogenic diet, but there are also a number of potentially serious health risks. It appears that most of these health risks can be mitigated with care.

This article is under construction. Caution: This a skeleton article, so only a rough outline exists. This may consist of semi-completed sections, isolated bullet point and notes to the author. You are welcome to read what exists so far, and feedback is welcomed. Email "feedback <at> fellrnr <dot> com"

1 Perspective

All diets have risk;

2 Context

My of the data on KD risks come from KD epilepsy, obesity, starvation.

3 Health Risks

3.1 Death

There have been two reported cases of sudden death of children on the Ketogenic Diet, probably due to selenium deficiency causing heart failure. Selenium deficiency can occur rapidly; one child was diagnosed with selenium deficiency and related heart problems before their scheduled 3 month selenium test. In addition, a study of 20 children on the Ketogenic Diet found heart rhythm abnormalities and heart enlargement in 3 (15%, diet duration 13 ± 8.4 months), and one had severe dilated cardiomyopathy. The effected children has normal selenium levels, but there was a significant correlation was found between the heart rhythm abnormality (QTc) and both bicarbonate and blood ketones, suggesting the level of acidosis or ketosis may be important factors.

3.2 Sodium Loss and Hypotension

Low carbohydrate diets cause of the kidneys to excrete more sodium. This is known as "natriuresis of starvation", and may be due to low insulin, increased dopamine excretion, or elevated Glucagon. If carbohydrate and sodium intakes are both limited, then the body will secrete the hormone aldosterone which will cause the kidneys to excrete potassium and conserve sodium. This loss of potassium can cause Muscle Cramps and heart arrhythmias, as well has the loss of Muscle Tissue.

3.3 Vitamin or mineral deficiency

The ketogenic diet is frequently deficient in vitamins and minerals, so supplementation is required with a carbohydrate free multivitamin/mineral.

• Separate supplementation of Calcium and Vitamin D is also recommended.
• Selenium is important to prevent heart problems (see above).
• Carnitine may also be required, depending on the results of testing.
• There are case reports of scurvy with the ketogenic diet, so additional supplementation with Vitamin C may be appropriate.

3.4 Constipation

Constipation is a common issue as the ketogenic diet is generally low in fiber. Even with supplementary fiber, constipation can still be a problem. This may be partly due to changes in the intestinal flora that occur with the ketogenic diet. There are also indications that some non-fiber carbohydrate parses far enough through the digestive tract to supply fuel to bacteria for fermentation.

3.5 Kidney Stones

5% of the children on the ketogenic diet for epilepsy suffer from kidney stones. A study showed that oral potassium citrate significantly decreased the occurrence of kidney stones. It has been shown that while carbonic anhydrase inhibitors are also a risk factor for kidney stones, carbonic anhydrase inhibitors while on the ketogenic diet does not further increase the risk. (Carbonic anhydrase inhibitors are a type of antiepileptic drug.) Maintaining a good level of hydration is important, and Oral citrates may be appropriate. The urine should be tested for blood at least once a week.

3.6 Hypoglycemia

Hypoglycemia (low blood sugar) seems to predominantly a risk if the ketogenic diet is started with a fast, and blood sugar levels should be checked every 6–8 hours during the first few days of the diet. Generally the ketogenic diet helps stabilize, and normalize blood sugar.

3.7 Acidosis

Uncontrolled diabetic patients can suffer from diabetic ketoacidosis, a life-threatening condition where very high levels of ketones are produced. In diabetic ketoacidosis not only are their high levels of ketones, but also their blood glucose is high, and there is often Potassium depletion and dehydration (citation required.) Acidosis is not a common problem on the ketogenic diet, but it can occur and symptoms are lethargy, Nausea, vomiting, and headache.

3.8 Elevated cholesterol and blood lipid changes

About 30% of children on the ketogenic diet experience elevated cholesterol levels, but this is normally transient, and the levels return to baseline after 6-12 months. Broader anecdotal evidence suggests that some people's cholesterol improves, while others cholesterol levels degrade. The health implications of cholesterol while on a Ketogenic Diet are unclear. If cholesterol levels are a concern, then the Ketogenic Ratio could be reduced, the percentage of unsaturated fats increased, MCT can be added, or carnitine can be supplemented.

3.9 Bone fractures

Children on the ketogenic diet suffer a higher rate of bone fractures, with 20% of children on the diet for 6+ years having fractures. Children on the ketogenic diet have poorer bone health, lower vitamin D levels, lower intakes of calcium and vitamin D, and lower Bone Mineral Content. However, epilepsy medications are associated with bone loss and calcium metabolism, so this may also be a contributory factor.

3.10 Growth reduction

Children treated with the ketogenic diet can have growth reduction. However, early uses of the ketogenic diet for epilepsy included calorie restriction below the recommended level for the child, as partial starvation was believed to be important for reducing seizures.

3.11 Fatty Liver

There are case reports of children on the MCT Diet having fatty infiltration of the liver. It's unclear how common this problem is. ("Fatty liver and medium chain triglyceride (MCT) diet.pdf").

3.12 Fat Intake Imbalance

When increasing the geometry fat intake, it is easy to get too much Omega-6. They are anecdotal reports that excessive Omega-6 can cause digestive problems, as well as longer-term health issues. The general recommendation is to avoid too much Omega-6, and aim for saturated or monounsaturated fats.

3.13 Insulin Resistance

While the Ketogenic Diet can be beneficial for those suffering from Insulin Resistance or diabetes, there are also concerns that the Ketogenic Diet may also result in some insulin resistance. This would not be expected to be an issue while on a Ketogenic Diet, but it may mean that care should be taken when exiting the Ketogenic Diet.

3.14 Thirst and Hydration

Ketones may reduce thirst.

3.15 Thyroid

Investigate further.

3.16 Gout

The ketogenic diet can produce an initial rise in the level of uric acid in the blood and the level of uric acid returns to baseline after 4-6 weeks, but some individuals can develop gout.

4 Contraindications

There are a number of contraindications for the ketogenic diet, including genetic deficiencies in fat metabolism. A discussion of these contraindications is outside of the scope of this article.

5 See Also

• The classifications and types of Low Carbohydrate Diet.
• An introduction to the Ketogenic Diet.
• My experiences with ultrarunning on the Ketogenic Diet
  • How the Ketogenic Diet can be used for the treatment and management of disease.
    • Using the Ketogenic Diets to mitigate and treat Epilepsy
    • How Ketogenic Diets might help with Cancer
    • A look at the possible mechanisms of action of the Ketogenic Diet
  • Health Risks of the Ketogenic Diet
    • Health Checks for the Ketogenic Diet
    • Supplements for the Ketogenic Diet
  • The time frame and changes that occur with Ketoadaptation
  • What are Ketones
    • How to measure Ketones
    • What ketone levels to aim for
  • The pros and cons of the Ketogenic Diet for athletes
    • The Science of Ketogenic Exercise
  • The Types of Ketogenic Diet
    • The "traditional" Ketogenic Diet based on the Ketogenic Ratio
      • The ways the Ketogenic Ratio can be calculated
        • The different definitions of Net Carbohydrates
    • Low Glycemic Index Treatment
    • MCT Diet
      • MCT
    • Modified Atkins Diet (M.A.D.)
• My Ketogenic Recipes
• Non-Ketogenic Low Carbohydrate Diets