All participants will be assigned to the 3-month ketogenic diet intervention. Study partners will be instructed to assist participants in adherence to a 1:1 ketogenic diet (approximately 70% fat, <10% carbohydrate, and 20% protein). Participants will be provided medium chain triglyceride oil with a target intake of 1-2 tablespoons per day and micronutrient supplements consisting of multivitamin, vitamin D, calcium, and phosphorus. After the 3-month ketogenic diet, participants will complete a 1-month washout period in which they halt adherence to the ketogenic diet and resume their normal diet.

All participants will be assigned to the 3-month 1:1 ketogenic diet intervention (approximately 70% fat, <10% carbohydrate, and 20% protein).

Participants will measure and report daily urinary ketone status using Ketostix (Bayer, Germany).

Serum beta-hydroxybutyrate levels will be measured at five monthly study visits; baseline prior to diet initiation, three monthly collections during the ketogenic diet intervention, and after the 1-month washout return to a regular diet.

Global cognitive performance will be assessed by a psychometrician using the Alzheimer's Disease Assessment Scale Cognitive Subscale (ADAS-Cog). The ADAS-Cog is an Alzheimer's disease specific, multi-domain cognitive assessment scored from 0-70 points with higher scores indicating poorer cognitive performance.