Determination of Protein Requirement in Elderly Male 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 dietary reference intakes (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 indicator amino acid oxidation (IAAO), our 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 national health and nutrition examination survey (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 male elderly subjects between the ages of 65 - 75 years using the IAAO technique.
|Study Design:||Intervention Model: Single Group Assignment
Masking: Open Label
|Official Title:||Use of Indicator Amino Acid Oxidation Technique to Determine Protein Requirement of Elderly Male Subjects 65-75 Yrs Old.|
- Urine (for measurement of 13C phenylalanine enrichment) and breath (for measurement of 13CO2 enrichment) samples will be collected on day 3 of the experiment between the 4th and 5th meal and after the 6th and 7th meal. [ Time Frame: 10 months ] [ Designated as safety issue: No ]
|Study Start Date:||March 2012|
|Estimated Study Completion Date:||December 2013|
|Estimated Primary Completion Date:||December 2013 (Final data collection date for primary outcome measure)|
Experimental: protein intake
protein intake randomly fed from deficient to excess
Dietary Supplement: protein intake
on the study day, the diet will be provided as free amino acids,with calories made up by a liquid diet and protein free cookies. Protein intake will be varied at 0.2, 0.5, 0.7, 0.9, 1.0, 1.2, 1.5, 1.8, and 2.0 g.kg/day
|Contact: Glenda Courtney-Martin, PhD, RDfirstname.lastname@example.org|
|The Hospital for Sick Children||Recruiting|
|Toronto, Ontario, Canada, M5G 1X8|
|Contact: Glenda Courtney-Martin, PhD, RD 416-813-5744 email@example.com|
|Principal Investigator: Paul Pencharz, MD. PhD|