Selenium deficiency associated with cardiomyopathy: a complication of the ketogenic diet.
Level 4 - case-series / case-control
Prospective case series and single case report without a control group
PubMed 12681013 · doi:10.1046/j.1528-1157.2003.26102.x
What was done
Following an index case of cardiomyopathy in a child on the ketogenic diet (KD) for intractable epilepsy, whole-blood or serum selenium levels were evaluated prospectively every 3 months in children already receiving or initiating the KD (1 index case plus 39 additional children).
What was found
The index case had no detectable whole-blood selenium and echocardiographic evidence of cardiomyopathy despite normal physical exam and ECG. Among 39 additional children, 8 had selenium levels below the normal reference range (6 at initial testing, 2 on follow-up testing; total deficient across the cohort was 9 of 40, or ~20%). The 8 other deficient children had normal cardiology evaluations. Selenium supplementation normalized levels in all children, with deficiency developing in some patients after only a few months on the diet.
Why it matters
The ketogenic diet may fail to provide adequate trace minerals like selenium, risking rare but severe complications such as nutritional cardiomyopathy. It demonstrates the necessity of routine micronutrient monitoring and targeted supplementation in pediatric KD regimens.
Limits
This is a single-center prospective case series of only 40 patients with no non-diet control group. The abstract does not provide exact numeric selenium values or reference ranges, and only one patient manifested clinical cardiac dysfunction.
Cited by
- supports Poorly formulated ketogenic diets have led to selenium deficiency and fatal cardiomyopathy in published case reports.