In this RCT investigating the effect of an adjunctive modified atkins diet on seizure frequency in adults iwht difficult to treat focal epilepsy, the authors found a significant reduction in seizure frequency in the diet group compared to the controls, but only for a moderate benefit (>25% seizure reduction) among those who completed the intervention. Seizure response varied considerably between individuals, perhaps negatively influenced by a drop in serum concentrations of antiepileptic drugs.
Kverneland (2018). "Effect of modified Atkins diet in adults with drug-resistant focal epilepsy: A randomized clinical trial." Epilepsia.