Effects of Casein Protein on Metabolism When Taken Prior to Sleep and in the Morning

The purpose of this study is to investigate the effect of casein protein consumption both prior to sleep as well first thing in the morning on metabolism (increase satiety and appetite, lower resting metabolic rate, and lower blood sugar levels), when compared to nighttime protein or placebo consumption alone. Protein itself is a macronutrient that not only helps the body repair itself, and play a critical role in growth, it also aids in increasing satiety and decreasing appetite. Casein protein specifically is slow digesting dairy protein which may impact the body's metabolism for a longer period than other dairy proteins such as whey. The literature demonstrates nighttime protein ingestion prior to sleep increases metabolic rate and satiety the next morning. However, there appears to be no data on the metabolic effects of protein ingested both at night and in the morning.

Study Overview

• Status: Active, not recruiting
• Conditions: Metabolism
• Intervention / Treatment: Dietary supplement: protein or placebo

• Study Type: Interventional
• Enrollment (Actual): 15
• Phase: Early Phase 1

Contacts and Locations

Study Locations

• United States
  • Ohio
    • Athens, Ohio, United States, 45701
      • Ohio University Exercise Physiology Lab

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• male
• aged 18-30

Exclusion Criteria:

• lactose intolerant
• having known sleep issues
• being on a schedule that is not uniform week to week
• those who do not eat animal-based diets
• any known or suspected food allergies
• any known health conditions (cardiovascular disease, IBS, high blood pressure, diabetes, crohn's disease)
• those that have disordered eating
• unwillingness to take blood sugar four times a day
• being a female

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Double

Number of Arms

4

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: PRO pm, PRO am; Participants arrive to the lab, complete 30 mins resting metabolic rate assessment. Then they are provided with a shake to drink 30 mins before bed. They return to the lab the following morning for 30 min RMR, drink another shake and do 30 mins RMR before leaving the lab.	Dietary supplement: protein or placebo; casein protein (30g) or placebo (maltodextrin, 30g)
Experimental: PRO pm, PLAC am; Participants arrive to the lab, complete 30 mins resting metabolic rate assessment. Then they are provided with a shake to drink 30 mins before bed. They return to the lab the following morning for 30 min RMR, drink another shake and do 30 mins RMR before leaving the lab.	Dietary supplement: protein or placebo; casein protein (30g) or placebo (maltodextrin, 30g)
Experimental: PLAC pm, PRO am; Participants arrive to the lab, complete 30 mins resting metabolic rate assessment. Then they are provided with a shake to drink 30 mins before bed. They return to the lab the following morning for 30 min RMR, drink another shake and do 30 mins RMR before leaving the lab.	Dietary supplement: protein or placebo; casein protein (30g) or placebo (maltodextrin, 30g)
Placebo Comparator: PLAC pm, PLAC pm; Participants arrive to the lab, complete 30 mins resting metabolic rate assessment. Then they are provided with a shake to drink 30 mins before bed. They return to the lab the following morning for 30 min RMR, drink another shake and do 30 mins RMR before leaving the lab.	Dietary supplement: protein or placebo; casein protein (30g) or placebo (maltodextrin, 30g)

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
resting metabolic rate	indirect calorimetry to measure oxygen consumption (V02) and respiratory quotient (RQ)	baseline, during the intervention
blood glucose	fasting and pre-meal blood glucose	baseline, during the intervention

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
dietary intake	food logs used to track food intake during all trial visits	during the intervention

Collaborators and Investigators

• Sponsor: Ohio University

Study record dates

Study Major Dates

• Study Start (Actual): October 1, 2022
• Primary Completion (Actual): May 1, 2024
• Study Completion (Estimated): December 31, 2025

Study Registration Dates

• First Submitted: January 31, 2024
• First Submitted That Met QC Criteria: February 7, 2024
• First Posted (Actual): February 9, 2024

Study Record Updates

• Last Update Posted (Actual): July 30, 2025
• Last Update Submitted That Met QC Criteria: July 28, 2025
• Last Verified: July 1, 2025

More Information

Terms related to this study

• Keywords: Metabolism
• Other Study ID Numbers: 22-F-7

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No