Determining the dietary tryptophan needs of older adults

The Tryptophan Requirement in Healthy Adults Over 60 Years

Not applicable Interventional The Hospital for Sick Children · NCT06283706

This study is testing how much tryptophan older adults need in their diet to stay healthy and support their body's protein needs.

Quick facts

PhaseNot applicable
Study typeInterventional
Enrollment40 (estimated)
Ages60 Years to 90 Years
SexAll
SponsorThe Hospital for Sick Children Academic / other
Locations1 site (Toronto, Ontario)
Trial IDNCT06283706 on ClinicalTrials.gov

What this trial studies

This study investigates the dietary requirements for tryptophan, an essential amino acid, in healthy adults aged 60 to 90 years. Using the Indicator Amino Acid Oxidation method, the research aims to establish accurate tryptophan intake levels necessary for protein synthesis and overall health in older adults. Participants will undergo health assessments, including blood tests, to ensure they meet the eligibility criteria and can tolerate the dietary interventions. The findings will contribute to better dietary planning for the aging population.

Who should consider this trial

Good fit: Ideal candidates for this study are healthy adults aged 60 to 90 years with a BMI under 30 who are willing to participate and provide consent.

Not a fit: Patients with chronic diseases or acute illnesses affecting protein metabolism, or those with significant dietary restrictions, may not benefit from this study.

Why it matters

Potential benefit: If successful, this study could lead to improved dietary guidelines that enhance the health and well-being of older adults.

How similar studies have performed: Previous studies have successfully determined amino acid requirements in different populations, suggesting that this approach may yield valuable insights for older adults as well.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Consent provided.
* Aged 60 to 90 years old.
* In good general health as evidenced by medical history, physical health and blood draw.
* Fasting blood glucose, hemoglobin A1c (HbA1c), urea, creatinine.
* Willingness to participate in the study.
* BMI \<30 kg/m2.

Exclusion Criteria:

* Presence of chronic disease and/or acute illness known to affect protein/amino acid metabolism (e.g. HIV, diabetes, taking medications known to affect protein/AA metabolism (e.g. steroids).
* Inability to tolerate the diet (i.e. allergy).
* Significant weight loss during the past month or consumption of weight reducing diets.
* Significant caffeine consumption (\>2 cups per day).
* Significant consumption of alcohol (\>1 drink per day i.e. 1 beer or ½ glass of wine).
* Unwilling to have blood drawn from a venous access or using a ventilated hood indirect calorimeter for the purposes of the study.

Where this trial is running

Toronto, Ontario

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Healthy Agingelderlyhealthytryptophan requirementindicator amino acid oxidationstable isotopes
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.