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Dangers of Zero-Carb Diets - No 4 kidney stones

Dangers of Zero-Carb Diets, IV: Kidney Stones | Perfect Health Diet

Conclusion

Zero-carb dieters are at risk for

  • Excess renal oxalate from failure to recycle vitamin C;
  • Excess renal uric acid from disposal of nitrogen products of gluconeogenesis and ketogenesis;
  • Salt and other electrolyte deficiencies from excretion of oxalate, urea and uric acid; and
  • Dehydration.

These four conditions dramatically elevate the risk of kidney stones.

To remedy these deficiencies, we recommend that everyone who fasts or who follows a zero-carb diet obtain dietary and supplemental antioxidants, eat salt and other electrolytes, and drink lots of water.

Also, unless there is a therapeutic reason to restrict carbohydrates, it is best to obtain about 20% of calories from carbs in order to relieve the need to manufacture glucose and ketones from protein. This will substantially reduce uric acid excretion. If it also reduces vitamin C degradation rates, as we argued in our last post, then it will substantially reduce oxalate excretion as well.

Related Posts

Other posts in this series:

  1. Dangers of Zero-Carb Diets, I: Can There Be a Carbohydrate Deficiency? Nov 10, 2010.
  2. Dangers of Zero-Carb Diets, II: Mucus Deficiency and Gastrointestinal Cancers A Nov 15, 2010.
  3. Danger of Zero-Carb Diets III: Scurvy Nov 20, 2010.

References

[1] Furth SL et al. Risk factors for urolithiasis in children on the ketogenic diet. Pediatr Nephrol. 2000 Nov;15(1-2):125-8. http://pmid.us/11095028.

[2] Herzberg GZ et al. Urolithiasis associated with the ketogenic diet. J Pediatr. 1990 Nov;117(5):743-5. http://pmid.us/2231206.

[3] Sampath A et al. Kidney stones and the ketogenic diet: risk factors and prevention. J Child Neurol. 2007 Apr;22(4):375-8. http://pmid.us/17621514.

[4] “Ketogenic diet,” Wikipedia, http://en.wikipedia.org/wiki/Ketogenic_diet.

[5] Groesbeck DK et al. Long-term use of the ketogenic diet. Dev Med Child Neurol. 2006 Dec;48(12):978-81. http://pmid.us/17109786.

[6] Taylor EN et al. DASH-style diet associates with reduced risk for kidney stones. J Am Soc Nephrol. 2009 Oct;20(10):2253-9. http://pmid.us/19679672.

[7] Gutman AB. Significance of uric acid as a nitrogenous waste in vertebrate evolution. Arthritis Rheum. 1965 Oct;8(5):614-26. http://pmid.us/5892984.

[8] Boyle JA et al. Serum uric acid levels in normal pregnancy with observations on the renal excretion of urate in pregnancy. J Clin Pathol. 1966 Sep;19(5):501-3. http://pmid.us/5919366.

[9] Linster CL, Van Schaftingen E. Vitamin C. Biosynthesis, recycling and degradation in mammals. FEBS J. 2007 Jan;274(1):1-22. http://pmid.us/17222174.

[10] Marengo SR, Romani AM. Oxalate in renal stone disease: the terminal metabolite that just won’t go away. Nat Clin Pract Nephrol. 2008 Jul;4(7):368-77. http://pmid.us/18523430.

[11] Taylor EN et al. Fatty acid intake and incident nephrolithiasis. Am J Kidney Dis. 2005 Feb;45(2):267-74. http://pmid.us/15685503.

[12] Taylor EN, Curhan GC. Oxalate intake and the risk for nephrolithiasis. J Am Soc Nephrol. 2007 Jul;18(7):2198-204. http://pmid.us/17538185.