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Metabolic Availability of Tryptophan From White Maize

Not Applicable
Completed
Conditions
Healthy
Registration Number
NCT02402179
Lead Sponsor
The Hospital for Sick Children
Brief Summary

Our objective is to determine the metabolic availability of Tryptophan in white maize using the indicator amino acid oxidation (IAAO) technique in adult men.

Detailed Description

Our objective is to determine the metabolic availability of Tryptophan in white maize. Seven young, healthy, male adults will receive graded levels (13.2, 26.4, 39.7, 52.9) of tryptophan requirement of 3.78 mg/kg/d as a crystalline amino acid (AA) mixture and a porridge of white cornmeal protein respectively.

Recruitment & Eligibility

Status
COMPLETED
Sex
Male
Target Recruitment
7
Inclusion Criteria
  • Healthy Adult males (20-49years old).
  • Stable body weight
  • Not on any medications that could affect protein and amino acid metabolism e.g. steroids.
Exclusion Criteria
  • Recent weight loss within the last 3 months or on weight reducing diet.
  • Unwillingness to participate or unable to tolerate the diet.

Study & Design

Study Type
INTERVENTIONAL
Study Design
SINGLE_GROUP
Primary Outcome Measures
NameTimeMethod
Metabolic Availability of Tryptophan in Corn9 hours

The quality of corn protein will be assessed by measuring the amount of its tryptophan available for protein synthesis (metabolic availability) using the slope ration method. The oxidation of the indicator amino acid phenylalanine will be measured in response to feeding graded intakes of tryptophan in a reference protein patterned after egg protein, and provided as a crystalline amino acid mixture. The pattern of oxidation of phylalanine in response to tryptophan provided in corn will be compared to the pattern of oxidation obtained from feeding the reference protein. On each study day, subjects will be fed 8 hourly meals and breath samples will be taken to measure the oxidation of phenylalanine. Samples will be collected at baseline after the fourth meal, and half hourly, beginning 2.5 hrs after the 5th meal. Breath samples will be analyzed for 13CO2 enrichment.

Secondary Outcome Measures
NameTimeMethod

Trial Locations

Locations (1)

The Hospital for Sick Children

🇨🇦

Toronto, Ontario, Canada

The Hospital for Sick Children
🇨🇦Toronto, Ontario, Canada

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