Impact of a Modified Ketogenic Diet on Seizure Activity, Biochemical Markers, Anthropometrics and Gastrointestinal Symptoms in Adults with Epilepsy
Authors: Schuchmann Courtney Ann , Nurko Ilana , Rasmussen Heather , Roehl Kelly , Tangney Christy , Send Stephanie , Maruschak Krista , Balabanov Antoaneta 
Published: November 2023

The classic low‐carbohydrate, high‐fat ketogenic diet (KD) effectively reduces seizure frequency in children with epilepsy. However, limited studies have been conducted in adults with a modified KD that liberalizes daily carbohydrate (CHO) quantity. Therefore, the objective of this study was to determine the impact of a modified KD on seizure activity, biochemical markers, anthropometrics, and gastrointestinal (GI) symptoms in adults with epilepsy. Enrolled patients from the Rush University Medical Center Clinic for Dietary Treatment of Epilepsy followed a modified KD of 15–50 net g of CHO/d for three months. Two 24‐hour dietary recalls (ASA24), seizure frequency, laboratory and anthropometric measures, and GI symptoms (Gastrointestinal Symptom Rating Scale, ranging 1 [no discomfort] to 7 [very severe discomfort]) were obtained at baseline and three months. Twelve of 31 enrolled participants followed up with dietary data at three months. These participants were primarily white (67.7%), female (50.0%), aged 39 (25, 44) (median [IQR]), and had a baseline BMI of 32.6 (28.7,39.1) kg/m2. Ten subjects (83.3%) were compliant based on 75 g net CHO/d. All nutrients were adjusted per 1000 kcals to account for variance in nutrient density. Net CHO intake decreased from 104 (55, 117) g to 21 (12, 53) g, p=0.039; sugar was significantly reduced at 3 months (p=0.006). Increases were observed for total fat (22.1 g increase [p=0.039]), as well as monounsaturated fatty acids (8.8 g increase [p=0.039]) and saturated fat (6.8 g increase [p=0.039]). Seizure frequency (n=9) was reduced on the diet (3 [1, 13] vs 2 [0, 3.5] seizures/month at baseline and 3‐months, respectively; p=0.043). Two subjects experienced a beneficial change in seizure frequency of ≥ 50%, and 3 participants experienced a reduction in seizure frequency of < 50%. Although not statistically significant, low‐density lipoprotein cholesterol trended up from 131 (105, 154) mg/dL to 144 (122, 173) mg/dL. Similarly, high‐density lipoprotein cholesterol increased from 57 (45, 70) mg/dL to 69 (38, 76) mg/dL (p= 0.75), and triglycerides trended down from 96 (78, 144) mg/dL to 91 (78, 123) mg/dL (p=0.24) (n=7). Weight (n=8) decreased from a median of 103 (82, 109) lbs to 96.5 (81, 98) lbs (p=0.021), BMI (n=8) decreased by approximately 3 kg/m2, and waist circumference (n=6) decreased from 45 (39, 47) inches to 41 (33, 42) inches (p=0.017 and p=0.043, respectively). Overall baseline GI scores (n=4) were low, with a median of 1.3 (1.1, 2.1), and did not change with a modified KD. In conclusion, amongst adults with epilepsy prescribed a modified KD, diet adherence was evident with reductions in CHO and parallel increases in fat consumption. Moreover, participants experienced meaningful reductions in seizure frequency, weight, BMI and waist circumference. Thus, a modified KD diet may be a beneficial treatment option to reduce seizure activity and adiposity in adults with epilepsy.