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

Status

Active, not recruiting

Phases

Early Phase 1

Study type

Interventional

Source

ClinicalTrials.gov

Registry ID

NCT06250270

Enrollment

Registered

2024-02-09

Start date

2022-10-01

Completion date

2025-12-31

Last updated

2025-07-30

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Metabolism

Keywords

Metabolism

Brief summary

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.

Interventions

DIETARY_SUPPLEMENTprotein or placebo

casein protein (30g) or placebo (maltodextrin, 30g)

Study design

Allocation

RANDOMIZED

Intervention model

CROSSOVER

Primary purpose

TREATMENT

Masking

DOUBLE (Subject, Investigator)

Masking description

Blinded pre-made packets of protein or placebo with sample coding in a sealed envelope until the end of the study

Eligibility

Sex/Gender

MALE

Age

18 Years to 30 Years

Healthy volunteers

Yes

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

Design outcomes

Primary

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

Secondary

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

Countries

United States

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026