Modified ketogenic diets in adults with refractory epilepsy: Efficacious improvements in seizure frequency, seizure severity, and quality of life

Epilepsy Behav. 2019 Apr:93:113-118. doi: 10.1016/j.yebeh.2018.12.010. Epub 2019 Mar 10.


Objective: This study evaluates the efficacy of a modified ketogenic diet (MKD) on seizure frequency, severity, and quality of life (QOL), as well as potential complications of MKD therapy among adults with drug-resistant epilepsy (DRE).

Methods: Changes in seizure frequency, severity, QOL, and side effects were retrospectively examined among adults, ≥17 years of age, with DRE (≥2 antiepileptic drugs [AEDs]), after 3 months of MKD therapy. Attention was paid to medication or vagus nerve stimulator (VNS) changes as well to evaluate potential confounders.

Results: A total of 60% (n = 33) of the 55 individuals reported ≥50% seizure frequency improvement, 42 (76%) reported improvement in seizure severity, and 48 (87%) reported improvement in QOL. More patients following a modified ketogenic diet - 15 g net carbohydrate daily (MKD-15) (95%) compared with a MKD-50 (69%) reported improvement in QOL (p = 0.02). Weight among the entire sample declined from 77.5 (20) kg to 73.9 (19.0) kg (p < 0.0001), and total cholesterol (TC), low density lipoprotein (LDL), and total cholesterol:high density lipoprotein (TC:HDL) increased significantly (p = 0.03, p = 0.04, and p = 0.02, respectively). Free carnitine values were available for a select number of patients, 26 (47%) at baseline, and 7 (13%) at follow-up, of which 8 (31%) at baseline, and 2 (29%) at follow-up had carnitine deficiency (<25 nmol/mL). Constipation was noted in 5 patients (9%), and no kidney stones were reported during the study period. There were no statistical differences in number or dose changes for AED or VNS during the study period.

Significance: Modified ketogenic diet therapies reduce seizure frequency and severity and improve QOL among adults with DRE with few side effects outside of weight loss, a desired outcome among many adults with DRE. More restrictive MKDs may offer improved seizure severity and QOL. Modified ketogenic diet therapy increases LDL cholesterol, which may be cardioprotective if related to an increase in LDL particle size with high saturated fat intake; however, more research is needed examining LDL particle size changes among those receiving MKD therapy.

Keywords: Lipid profile; Low glycemic index treatment; Modified Atkins diet; Quality of life; Seizure severity; Weight loss.

MeSH terms

  • Adolescent
  • Adult
  • Child
  • Diet, Carbohydrate-Restricted / methods
  • Diet, Ketogenic / methods*
  • Drug Resistant Epilepsy / diagnosis
  • Drug Resistant Epilepsy / diet therapy*
  • Drug Resistant Epilepsy / psychology*
  • Female
  • Humans
  • Male
  • Quality of Life / psychology*
  • Retrospective Studies
  • Seizures / diagnosis
  • Seizures / diet therapy*
  • Seizures / psychology*
  • Severity of Illness Index
  • Treatment Outcome