View source for 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.
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=Perspective=
All diets have risk; 

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

=Health Risks=

==Death==
There have been two reported cases of sudden death of children on the Ketogenic Diet, probably due to selenium deficiency causing heart failure<ref name="BankShemie2008"/>. Selenium deficiency can occur rapidly; one child was diagnosed with selenium deficiency and related heart problems before their scheduled 3 month selenium test<ref name="Sirikonda-2012"/>. 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<ref name="Best-2000"/>. 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. 

==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<ref name="Stenvinkel-1995"/>, increased dopamine excretion<ref name="Swaminathan-1983"/>, or elevated Glucagon<ref name="SaudekBoulter1973"/>. If carbohydrate and sodium intakes are both limited, then the body will secrete the hormone aldosterone<ref name="Phinney-2011-p312"/> which will cause the kidneys to excrete potassium and conserve sodium<ref name="Lote2012"/>. This loss of potassium can cause muscle cramps and heart arrhythmias, as well has the loss of muscle tissue.

==Vitamin or mineral deficiency==
The ketogenic diet is frequently deficient in vitamins and minerals, so supplementation is required with a carbohydrate free multivitamin/mineral<ref name="Kossoff-2011-p137"/>. 
* 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<ref name="Willmott-2008"/>, so additional supplementation with Vitamin C may be appropriate.

==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.

==Kidney Stones==
5% of the children on the ketogenic diet for epilepsy suffer from kidney stones<ref name="Sampath-2007"/>. A study showed that oral potassium citrate significantly decreased the occurrence of kidney stones<ref name="McNally-2009"/>. It has been shown that while [http://en.wikipedia.org/wiki/Carbonic_anhydrase_inhibitor 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<ref name="Kossoff-2002"/>. (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 [[Health Checks for the Ketogenic Diet| tested for blood]] at least once a week<ref name="Kossoff-2011-p109"/>. 

==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.

==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<ref name="Kossoff-2011-p318"/>.  

==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<ref name="Kossoff-2011-2512"/>. 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<ref name="Kossoff-2011-2522"/>.

==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<ref name="Kossoff-2011-p271"/>. 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<ref name="BergqvistSchall2008"/>. However, epilepsy medications are associated with bone loss and calcium metabolism<ref name="Kossoff-2011-p174"/>, so this may also be a contributory factor. 

==Growth reduction==
Children treated with the ketogenic diet can have growth reduction<ref name="Kossoff-2011-2533"/>. 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.

==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").

==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.

==Insulin Resistance ==
While the Ketogenic Diet can be beneficial for those suffering from insulin resistance or diabetes<ref name="Veech-2004"/>, there are also concerns that the Ketogenic Diet may also result in some insulin resistance<ref name="Jornayvaz2011"/>. 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. 

==Thirst and Hydration==
Ketones may reduce thirst<ref name="Kossoff-2011-2218"/>.

==Thyroid ==
Investigate further. 

==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<ref name="Phinney-2011-p343"/>.

=Contraindications=
There are a number of contraindications for the ketogenic diet, including [http://en.wikipedia.org/wiki/Fatty-acid_metabolism_disorder genetic deficiencies in fat metabolism]<ref name="Kossoff-2011-1864"/>. A discussion of these contraindications is outside of the scope of this article.

=References=
<references>
<ref name="Jornayvaz2011">F. R. Jornayvaz, Fibroblast growth factor 21, ketogenic diets, and insulin resistance, American Journal of Clinical Nutrition, volume 94, issue 3, 2011, pages 955–955, ISSN [http://www.worldcat.org/issn/0002-9165 0002-9165], doi [http://dx.doi.org/10.3945/ajcn.111.019646 10.3945/ajcn.111.019646]</ref>
<ref name="Veech-2004">RL. Veech, The therapeutic implications of ketone bodies: the effects of ketone bodies in pathological conditions: ketosis, ketogenic diet, redox states, insulin resistance, and mitochondrial metabolism., Prostaglandins Leukot Essent Fatty Acids, volume 70, issue 3, pages 309-19, Mar 2004, doi [http://dx.doi.org/10.1016/j.plefa.2003.09.007 10.1016/j.plefa.2003.09.007], PMID [http://www.ncbi.nlm.nih.gov/pubmed/14769489 14769489]</ref>
<ref name="Swaminathan-1983"> R. Swaminathan, G. Cope, M. Sheltawy, MR. Lee, JK. Wales, Dopamine excretion during natriuresis of starvation., Int J Obes, volume 7, issue 1, pages 31-5,  1983, PMID [http://www.ncbi.nlm.nih.gov/pubmed/6840964 6840964]</ref>
<ref name="SaudekBoulter1973">C. D. Saudek, P. R. Boulter, R. A. Arky, The Natriuretic Effect of Glucagon and Its Role in Starvation, Journal of Clinical Endocrinology & Metabolism, volume 36, issue 4, 1973, pages 761–765, ISSN [http://www.worldcat.org/issn/0021-972X 0021-972X], doi [http://dx.doi.org/10.1210/jcem-36-4-761 10.1210/jcem-36-4-761]</ref>
<ref name="Stenvinkel-1995">P. Stenvinkel, A. Ottosson-Seeberger, A. Alvestrand, J. Bolinder, Effect of insulin on renal sodium handling and renal haemodynamics in insulin-dependent (type 1) diabetes mellitus patients., Acta Diabetol, volume 32, issue 4, pages 230-4, Dec 1995, PMID [http://www.ncbi.nlm.nih.gov/pubmed/8750761 8750761]</ref>
<ref name="Lote2012">Christopher J. Lote [http://www.amazon.com/Principles-Renal-Physiology-Christopher-Lote/dp/0792360745 http://www.amazon.com/Principles-Renal-Physiology-Christopher-Lote/dp/0792360745] Principles of Renal Physiology], 22 June 2012, Springer, ISBN 978-1-4614-3785-7</ref>
<ref name="Willmott-2008"> NS. Willmott, RA. Bryan, Case report: scurvy in an epileptic child on a ketogenic diet with oral complications., Eur Arch Paediatr Dent, volume 9, issue 3, pages 148-52, Sep 2008, PMID [http://www.ncbi.nlm.nih.gov/pubmed/18793598 18793598]</ref>
<ref name="Sampath-2007"> A. Sampath, EH. Kossoff, SL. Furth, PL. Pyzik, EP. Vining, Kidney stones and the ketogenic diet: risk factors and prevention., J Child Neurol, volume 22, issue 4, pages 375-8, Apr 2007, doi [http://dx.doi.org/10.1177/0883073807301926 10.1177/0883073807301926], PMID [http://www.ncbi.nlm.nih.gov/pubmed/17621514 17621514]</ref>
<ref name="McNally-2009"> MA. McNally, PL. Pyzik, JE. Rubenstein, RF. Hamdy, EH. Kossoff, Empiric use of potassium citrate reduces kidney-stone incidence with the ketogenic diet., Pediatrics, volume 124, issue 2, pages e300-4, Aug 2009, doi [http://dx.doi.org/10.1542/peds.2009-0217 10.1542/peds.2009-0217], PMID [http://www.ncbi.nlm.nih.gov/pubmed/19596731 19596731]</ref>
<ref name="Kossoff-2002"> EH. Kossoff, PL. Pyzik, SL. Furth, HD. Hladky, JM. Freeman, EP. Vining, Kidney stones, carbonic anhydrase inhibitors, and the ketogenic diet., Epilepsia, volume 43, issue 10, pages 1168-71, Oct 2002, PMID [http://www.ncbi.nlm.nih.gov/pubmed/12366731 12366731]</ref>
<ref name="BankShemie2008">Ilana M. Bank, Sam D. Shemie, Bernard Rosenblatt, Chantal Bernard, Andrew S. Mackie, Sudden Cardiac Death in Association With the Ketogenic Diet, Pediatric Neurology, volume 39, issue 6, 2008, pages 429–431, ISSN [http://www.worldcat.org/issn/08878994 08878994], doi [http://dx.doi.org/10.1016/j.pediatrneurol.2008.08.013 10.1016/j.pediatrneurol.2008.08.013]</ref>
<ref name="Best-2000"> TH. Best, DN. Franz, DL. Gilbert, DP. Nelson, MR. Epstein, Cardiac complications in pediatric patients on the ketogenic diet., Neurology, volume 54, issue 12, pages 2328-30, Jun 2000, PMID [http://www.ncbi.nlm.nih.gov/pubmed/10881264 10881264]</ref>
<ref name="Sirikonda-2012"> NS. Sirikonda, WD. Patten, JR. Phillips, CJ. Mullett, Ketogenic diet: rapid onset of selenium deficiency-induced cardiac decompensation., Pediatr Cardiol, volume 33, issue 5, pages 834-8, Jun 2012, doi [http://dx.doi.org/10.1007/s00246-012-0219-6 10.1007/s00246-012-0219-6], PMID [http://www.ncbi.nlm.nih.gov/pubmed/22367552 22367552]</ref>
<ref name="BergqvistSchall2008">A. C. Bergqvist, J. I Schall, V. A Stallings, B. S Zemel, Progressive bone mineral content loss in children with intractable epilepsy treated with the ketogenic diet, American Journal of Clinical Nutrition, volume 88, issue 6, 2008, pages 1678–1684, ISSN [http://www.worldcat.org/issn/0002-9165 0002-9165], doi [http://dx.doi.org/10.3945/ajcn.2008.26099 10.3945/ajcn.2008.26099]</ref>
<ref name="Kossoff-2011-1864">Eric. Kossoff, [http://www.amazon.com/Ketogenic-Diets-Eric-H-Kossoff/dp/1936303108 Ketogenic diets : treatments for epilepsy and other disorders], date 2011, publisher Demos Health, location New York, isbn 1-936303-10-8, Kindle Offset 1864</ref>
<ref name="Kossoff-2011-2218">Eric. Kossoff, [http://www.amazon.com/Ketogenic-Diets-Eric-H-Kossoff/dp/1936303108 Ketogenic diets : treatments for epilepsy and other disorders], date 2011, publisher Demos Health, location New York, isbn 1-936303-10-8, Kindle Offset 2218</ref>
<ref name="Kossoff-2011-2533">Eric. Kossoff, [http://www.amazon.com/Ketogenic-Diets-Eric-H-Kossoff/dp/1936303108 Ketogenic diets : treatments for epilepsy and other disorders], date 2011, publisher Demos Health, location New York, isbn 1-936303-10-8, Kindle Offset 2533</ref>
<ref name="Kossoff-2011-p174">Eric. Kossoff, [http://www.amazon.com/Ketogenic-Diets-Eric-H-Kossoff/dp/1936303108 Ketogenic diets : treatments for epilepsy and other disorders], date 2011, publisher Demos Health, location New York, isbn 1-936303-10-8, Page 174</ref>
<ref name="Kossoff-2011-p271">Eric. Kossoff, [http://www.amazon.com/Ketogenic-Diets-Eric-H-Kossoff/dp/1936303108 Ketogenic diets : treatments for epilepsy and other disorders], date 2011, publisher Demos Health, location New York, isbn 1-936303-10-8, Page 271</ref>
<ref name="Kossoff-2011-2522">Eric. Kossoff, [http://www.amazon.com/Ketogenic-Diets-Eric-H-Kossoff/dp/1936303108 Ketogenic diets : treatments for epilepsy and other disorders], date 2011, publisher Demos Health, location New York, isbn 1-936303-10-8, Kindle Offset 2522</ref>
<ref name="Kossoff-2011-2512">Eric. Kossoff, [http://www.amazon.com/Ketogenic-Diets-Eric-H-Kossoff/dp/1936303108 Ketogenic diets : treatments for epilepsy and other disorders], date 2011, publisher Demos Health, location New York, isbn 1-936303-10-8, Kindle Offset 2512</ref>
<ref name="Kossoff-2011-p318">Eric. Kossoff, [http://www.amazon.com/Ketogenic-Diets-Eric-H-Kossoff/dp/1936303108 Ketogenic diets : treatments for epilepsy and other disorders], date 2011, publisher Demos Health, location New York, isbn 1-936303-10-8, Page 318</ref>
<ref name="Kossoff-2011-p109">Eric. Kossoff, [http://www.amazon.com/Ketogenic-Diets-Eric-H-Kossoff/dp/1936303108 Ketogenic diets : treatments for epilepsy and other disorders], date 2011, publisher Demos Health, location New York, isbn 1-936303-10-8, Page 109</ref>
<ref name="Kossoff-2011-p137">Eric. Kossoff, [http://www.amazon.com/Ketogenic-Diets-Eric-H-Kossoff/dp/1936303108 Ketogenic diets : treatments for epilepsy and other disorders], date 2011, publisher Demos Health, location New York, isbn 1-936303-10-8, Page 137</ref>
<ref name="Phinney-2011-p343">Phd Stephen D. Phinney MD, Rd Jeff S. Volek Phd, [http://www.amazon.com/The-Art-Science-Carbohydrate-Living/dp/0983490708 The Art and Science of Low Carbohydrate Living: An Expert Guide to Making the Life-saving Benefits of Carbohydrate Restriction Sustainable and Enjoyable], 2011, publisher Beyond Obesity LLC, isbn 978-0-9834907-0-8, Page 343</ref>
<ref name="Phinney-2011-p312">Phd Stephen D. Phinney MD, Rd Jeff S. Volek Phd, [http://www.amazon.com/The-Art-Science-Carbohydrate-Living/dp/0983490708 The Art and Science of Low Carbohydrate Living: An Expert Guide to Making the Life-saving Benefits of Carbohydrate Restriction Sustainable and Enjoyable], 2011, publisher Beyond Obesity LLC, isbn 978-0-9834907-0-8, Page 312</ref>
</references>