The Brain Ketone Body Challenge Imaging Study

After consuming a chilled 4 ounce shake which contains various dietary fats, cognitive
testing and dual-tracer Positron Emission Tomography scan will be completed. At Visit 1, each
participant will be randomized to Challenge A (low calorie Ensure®) or Challenge B (Ensure®
plus ketone esters). At Visit 2, each participant will undergo the remaining challenge (A or
B) prior to the second imaging session. Each visit is designed to be identical to the other
and only vary the dose of ketone esters. Randomization to either Challenge at Visit 1 will
ensure that test/re-test learning effects are equally distributed between the challenge
groups. This study consists of two visits that will take place over a two week period.

Inclusion Criteria:

- Diagnosis of Mild Cognitive Impairment (MCI)

- Stable medical condition

- Stable on medications for past 4 weeks

- Women must be post-menopausal

Exclusion Criteria:

- Diagnosis of neurodegenerative illness (except for MCI)

- History of a clinically significant stroke

- Current evidence or history in past year of focal brain lesion, head injury with loss
of consciousness or meeting any Diagnostic and Statistical Manual 4 (DSM-IV) criteria
for major psychiatric disorder including psychosis, major depression, bipolar
disorder, alcohol or substance abuse

- Diabetes that requires current use of diabetes medications

- Current use of cholesterol/lipid lowering medications

- History of epilepsy or seizure within past year

- Contraindications for imaging (e.g. claustrophobia or high prior radiation exposure)