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