This pilot study aims to determine the impact of whey protein supplementation on brain antioxidant levels and to assess the effects of whey protein supplementation on physical function, body composition, and cognition in pre-frail older adults.

Frailty is characterized by weakness, muscle loss, and physical impairment. It is suggested that long term oxidative stress might contribute to frailty. Glutathione (GSH), an antioxidant in cells, is needed to combat oxidative stress. Whey protein has the potential to increase brain antioxidant (GSH) levels by aiding in antioxidant synthesis. Frail older adults under-consume protein compared to healthy older adults.

Researchers want to see if supplementing with whey protein will improve brain antioxidant status in pre-frail older adults. They will measure this by using special Magnetic Resonance Imaging (MRI) scans.

Participants will be asked to complete a total of 4 study visits, all taking place on the University of Kansas Medical Center (KUMC) main campus. Two of these visits will include an MRI scan. Participation will last about 3 months.

Inclusion Criteria:

• Pre-frail according to Fried's phenotype
• Age 65 to 85
• Speak English as primary language and able to read and write in English
• Stable medication for ≥ 30 days
• Not already taking whey protein over the past 30 days

Exclusion Criteria:

• Acute or chronic kidney disease
• Recent major health concerns
• Insulin-requiring diabetes
• Cancer requiring chemotherapy or radiation within the past 5 years
• Cardiac event (i.e., MI, etc.) in the past year
• Dementia or neurodegenerative disease
• Clinical trial or investigational drug or therapy participation within 30 days of the screening visit or during enrollment in the current study
• MRI contraindications (pacemaker, aneurysm clips, artificial heart valves, metal fragments, foreign objects or claustrophobia)
• Dairy Allergy or excluding dairy from diet for other reasons
• Weight > 350 lbs.
• The presence of major psychiatric disorders within the past 3 years including depression, anxiety, and alcohol (over 3 drinks/day or a total of 18 drinks/week) or drug abuse.