Impact of Time Restricted Feeding on Daily Protein Requirements

Study Overview
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Brief Summary
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The investigators aim to assess 24-hour protein kinetics at two different levels of protein intake: 0.8 (RDA) and 1.6g/kg/day (2RDA) during a normal dietary (TRAD) and a time restricted feeding (TRF) pattern in older adults.

Detailed Description
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The investigators aim to assess 24-hour protein kinetics at two different levels of protein intake: 0.8 (RDA) and 1.6g/kg/day (2RDA) during a normal dietary (TRAD) and a time restricted feeding (TRF) pattern in older adults. Individuals in the TRF pattern will only consume food during a 6-hour eating period and fast for the remaining 18 hours. Individuals in the TRAD pattern will consume isocaloric and isonitrogenous (RDA or 2RDA) diet but consume an all-beef-breakfast. Participants will consume oral stable isotopes to measure muscle protein synthesis (MPS), whole-body muscle protein breakdown (MPB), and whole-body protein balance (WBPB). Appropriate muscle, blood samples, and urine will be collected throughout a 24-hour metabolic trial following a 2-day controlled diet.

Official Title
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Impact of Time Restricted Feeding on Daily Protein Requirements

Conditions
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Nutrition Disorders in Old Age

Intervention / Treatment
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* Other: isocaloric, isonitrogenous meals


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Men and women ages 50-75 years. BMI 20-30 kg/m2 inclusive. Capable of providing informed consent. COVID-19 negative and/or asymptomatic Exclusion Criteria: Subject who does not/will not eat animal protein sources. Body mass index <20 or >30. Hemoglobin <10g/dL at screening. Platelets <150,000/uL at screening. History of diabetes. History of chemotherapy or radiation therapy for cancer in the 6 months prior to enrollment. History of gastrointestinal bypass/reduction surgery. History of a chronic inflammatory disease (e.g. what?) Currently receiving androgen (e.g., testosterone) or anabolic (e.g., GH, IGF-I) therapy. Currently using prescription blood thinning medications. Currently using corticosteroid medications. Unable or unwilling to suspend aspirin use for 7 days prior to Visit 3. Unwilling to avoid using protein or amino-acid supplements during participation. Subjects who are unwilling to fast overnight. Participating in >200 minutes/week of vigorous exercise and/or >4 days/week of resistance training.

Ages Eligible for Study
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Minimum Age: 50 Years
Maximum Age: 75 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Other
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: TRF of RDA<br>A time-restricted model of consumption of the RDA of protein/day. | Other: isocaloric, isonitrogenous meals<br>* Participants will eat prepared study meals for 3 days that have either the RDA of protein per day or twice the RDA of protein per day.<br>|
| Active Comparator: TRAD of RDA<br>A typical American dietary ingestion pattern of the RDA of protein/day. | Other: isocaloric, isonitrogenous meals<br>* Participants will eat prepared study meals for 3 days that have either the RDA of protein per day or twice the RDA of protein per day.<br>|
| Experimental: TRF of 2RDA<br>A time-restricted model of consumption of twice the RDA of protein/day. | Other: isocaloric, isonitrogenous meals<br>* Participants will eat prepared study meals for 3 days that have either the RDA of protein per day or twice the RDA of protein per day.<br>|
| Experimental: TRAD of 2RDA<br>A typical American dietary ingestion pattern of twice the RDA of protein/day. | Other: isocaloric, isonitrogenous meals<br>* Participants will eat prepared study meals for 3 days that have either the RDA of protein per day or twice the RDA of protein per day.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Whole-body protein balance | Volume of net protein produced per unit of time | 24 hours |