Determination of Protein Requirement in Elderly Female Subjects 65-75 Yrs Old
Minimal data are available on protein requirements throughout the lifespan. Currently available recommendations are based on nitrogen balance data. The limitations of the nitrogen balance method have been well described. Importantly, nitrogen balanced underestimates requirements.
The current DRI requirement for healthy adult males is based on the reanalysis of the nitrogen balance date from Young and Scrimshaw. This data was reanalyzed statistically by Rand et al. and he concluded that the protein requirement of healthy adults was 0.65 and 0.83 (mean and RDA) g/kg/day of good quality protein. Using IAAO, the investigators group estimated the protein requirement of young men (mean age 27 years) to be 0.93 and 1.2 g/kg/day (mean and RDA).
Currently there are no studies on protein requirement in the elderly. In a recent nutrition survey conducted by NHANES, the authors concluded that adults between the ages of 51 - 70 years old consumed an average on 1.0 g/kg/day (ideal body weight) of protein which represents about 15 % of calories. Depending on the calculations used for ideal body weight some older adults could be getting higher or lower than requirement. There is no scientifically derived protein estimate for older adults. Therefore there is a need to measurer protein requirement in that population.
The goal of this study therefore is to measure the protein requirement of female elderly subjects between the ages of 65 - 70 years using the IAAO technique.
|Study Design:||Intervention Model: Crossover Assignment
Masking: Open Label
Primary Purpose: Health Services Research
|Official Title:||Use of Indicator Amino Acid Oxidation Technique to Determine Protein Requirement of Elderly Female Subjects 65-75 Yrs Old|
- 13CO2 production [ Time Frame: Study Day 3 ] [ Designated as safety issue: No ]Urine and breath samples will be collected on day 3 of the experiment in order to determine to rate of production of 13CO2, phenylalanine flux and oxidation.
|Study Start Date:||November 2011|
|Study Completion Date:||August 2012|
|Primary Completion Date:||August 2012 (Final data collection date for primary outcome measure)|
Experimental: protein intake
different levels of protein intake
Dietary Supplement: protein intake.
•Protein intakes will be varied at 0.2, 0.5, 0.7, 0.9,1.0, 1.2, 1.5, 1.8g, 2.0g/kg/day
|The Hospital for Sick Children|
|Toronto, Ontario, Canada, M5G1X8|
|Principal Investigator:||Paul Pencharz, MD||The Hospital for Sick Children|