Alzheimer disease (AD) is a dementing illness characterized by progressive neuronal degeneration, gliosis, and the accumulation of intracellular inclusions and extracellular deposits of amyloid in discrete regions of the basal forebrain, hippocampus, and the association cortices. Mild cognitive impairment (MCI) refers to individuals with cognitive impairment (often memory loss) that fails to meet clinical criteria for AD or another dementing illness.

This study is recruiting Mild Cognitive Impaired (MCI) patients from the Memory Clinic of the Jewish General Hospital only.

Inclusion Criteria:

Subjects meeting diagnostic criteria for MCI:

• Age 55-85
• Male or female
• Non-smoker

To ensure that the subject can physically fit in the scanner:

1. body weight ≤ 120 kg and
2. with a linear dimension max 55cm (shoulders or belly) Expected to remain in the greater Montreal area for the duration of study.

Exclusion Criteria:

• Presence of an active, systemic illness (e.g., cancer, rheumatoid arthritis, etc.) or other chronic neurological (e.g. Parkinson's disease, multiple sclerosis) or psychiatric (e.g. major depression, schizophrenia) disease.
• Subjects taking other experimental medications or psychotropic agents.
• Subjects with MRI contraindications such as pacemaker, aneurysm clips, artificial heart valves, metal fragments, foreign objects or claustrophobia.
• Ambulatory subjects: As wheelchair-bound subjects present additional difficulties for transportation and MRI scanning.

Musculoskeletal abnormalities that preclude the ability of the subject to lie on his/her back for 1hr during MRI scanning.

• Subjects who have a protein restricted diet as per their medical history.
• Pregnancy
• Subjects using N-acetylcysteine, α-lipoic acid supplements, other whey protein supplements or Vitamin C, within 2 months of enrolment and during the entire 6 months study period.
• Allergies to milk proteins/ Milk protein intolerance