The Role of Protein in Regulating Ad Libitum Energy Intake in Humans

Summary

The purpose of this project is to determine if protein is less likely to create positive energy balance when added to the diet compared to carbohydrate. To do this, the investigators will take detailed measurements of participant's baseline metabolic rate to understand their energy requirements. Then, the investigators will feed participants all their meals for two weeks, Monday-Friday, and measure their food intake. During one of the week-long feeding periods, participants will consume a shake made of egg protein that is \~20% of their energy requirements. During the other week, participants will consume a shake made of carbohydrate that is \~20% of their energy requirements. Participants will drink the assigned shake at the beginning of each of their daily three meals, and then they will be offered a 'regular' meal of unlimited quantity. Participants will not know that the investigators are measuring the food consumed after drinking the shake. Participants will drink the protein shake for the first week and carb-based shake for the second week, and vice versa-- depending on the randomization order. To account for energy expenditure, participants will wear an activity monitor, an accelerometer. Energy balance, measured as participant energy intake minus energy expenditure, will be our main outcome for each treatment. However, because participants may change their behavior if made aware of the true research question, the investigators will tell participants that the purpose of the study is to see how low fiber and high fiber shakes affect mood. The hypothesis is that during the week when participants consume the protein shake, they will remain in energy balance, but during the week of carbohydrate shake consumption, participants will have positive energy balance.

Conditions

• Energy Balance

Interventions

DIETARY_SUPPLEMENT

Consumption of NOW Foods eggwhite protein shake

Consumption of NOW Foods egg white protein shake at beginning of 3 daily meals that in total, is approximately 20% of caloric needs.

DIETARY_SUPPLEMENT

Consumption of NOW Foods maltodextrin shake

Consumption of NOW Foods maltodextrin shake at beginning of 3 daily meals that in total, is approximately 20% of caloric needs.

Sponsors & Collaborators

• Egg Nutrition Center

  collaborator OTHER

• University of Alabama at Birmingham

  lead OTHER

Principal Investigators

• David B Allison, PhD · University of Alabama at Birmingham

Study Design

Allocation

RANDOMIZED

Purpose

PREVENTION

Masking

DOUBLE

Model

CROSSOVER

Eligibility

Min Age

30 Years

Max Age

50 Years

Sex

ALL

Healthy Volunteers

Yes

Timeline & Regulatory

Start

2015-05-31

Primary Completion

2016-06-30

Completion

2016-06-30

Countries

• United States

Study Locations