For the intervention arm, an unblinded study team member will deliver and review the Nutrition After Surgery and postoperative supplementation instructions with the participant.

Additionally, an unblinded study team member will give each participant a 30-day supply of single-servings. They will be instructed to consume 1 packet per day for 30 days, reconstituted per instructions (see instructions file), after discharge from the hospital. The unblinded researchers will work with the coordinator team to provide participants with a plan for supplementation (normal or underweight participants) or meal replacement (overweight or obese patients). Participants will be instructed to keep track of their shake consumption on a daily basis. Shake consumption logs will be collected via REDCap surveys sent to participants and reviewed by the unblinded coordinators/investigators for adverse events and compliance.

The control arm receives the Nutrition After Surgery instructions, which provide guidelines for healthy eating after surgery but not the nutritional shake. The intervention arm receives the same instructions along with the nutrition shake mix and accompanying postoperative supplementation

The shake mixes will be dry shelf -stable powders prepared with ingredients readily available in the US food supply and contain a minimum of 990 mg total cocoa flavanols, with a profile to support general nutritional health including 10 g protein. Accordingly, each shake contains approximately 95 mg of caffeine, equivalent to a medium-sized cup of coffee. Based on prior studies of cognition, additional composition specifications are: 1600 mg DHA and up to 400 mg EPA and 550 mg choline; >250 mg epicatechin and epigallocatechin (plant polyphenols); multivitamin/mineral fortification to ensure 50-100% of all essential micronutrients except calcium (to prevent competitive absorption with other divalent cations). Participants will be given a supply of pre-portioned daily servings upon discharge from the hospital, for 30 days after surgery.

This aim will compare postoperative change in disability scores, as measured by World Health Organization Assessment Schedule 2.0 (WHODAS 2.0), from baseline to 1 month and baseline to 3 months. Results will be scored on a 5-point Likert scale and summed to a total score ranging 0 to 100, where 0 indicates no disability and 100 indicates full disability. The outcome will compare patients receiving a 30-day supply of daily nutritional shake and general healthy nutrition recommendations versus those only receiving general healthy nutrition recommendations without a provided shake

This aim will compare postoperative change in cognitive function, as measured by The Montreal Cognitive Assessment (T-MoCA), from baseline to 1 month and baseline to 3 months. Scores will range from 0 to 30 points, with higher scores indicating greater cognitive function. The outcome will compare patients receiving a 30-day supply of a daily nutritional shake and general healthy nutritional recommendations versus those receiving only healthy nutritional recommendations without a provided shake.

Mechanistic investigations of effects of multi-component nutrition food (MCN). We will collect and freeze blood specimens for a secondary analysis of blood markers of neural injury and inflammation that has been observed in surgical cohorts. No analysis of the samples will be performed currently. We will measure the proportion of patients with samples on the day of surgery and at postoperative day one.