Coffee Intake Biomarker Validation and Association With Respiratory Diseases

This proposed project aims to identify and validate biomarkers of coffee exposure in the Singapore population, and assess the association between coffee consumption (via biomarker measurements) and risk of respiratory diseases in a prospective multi-ethnic cohort in Singapore.

Specific Aim 1: To identify and quantify urinary/serum metabolite changes that are associated with coffee consumption in a dose-response intervention study.

Study Overview

• Status: Active, not recruiting
• Conditions: Coffee
• Intervention / Treatment: Dietary supplement: Coffee A; Dietary supplement: Coffee B; Dietary supplement: Tea

• Study Type: Interventional
• Enrollment (Estimated): 100
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Singapore
  • Singapore
    • Singapore, Singapore, Singapore, 117549
      • Saw Swee Hock School of Public Health, National University of Singapore

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Regular coffee drinkers aged 21-64 years old, Chinese ethnicity

Exclusion Criteria:

• Healthy individuals who are regular coffee and/or tea drinkers, aged 21-64 years old of Chinese ethnicity with no severe medical conditions and are physically-abled, can participate in the research. However, you cannot participate in or will be released from this study if the following conditions or situations apply to you:

  • Ineligible screening survey which will consist of basic demographic information and questions pertaining to inclusion/exclusion criteria such as age, gender, current medications, chronic illness, etc
  • Dislike drinking coffee and tea
  • Pregnant or breastfeeding
  • Certain medications including Zanaflex, Sirasalud, Ketanest S, Spravato and Ephedrine Sulfate (See full list of medication)
  • Present medical conditions: cancer, cardiometabolic diseases, endocrine diseases, depression, anxiety, caffeine/lactose intolerant, fear of needles and/or blood disorders
  • Recent history of major surgical operations
  • Past or current user of oral/systemic hormone treatment or therapies
  • Taken antibiotics in the last 3 months
  • Taking nutritional supplements (that contains coffee/tea-related compounds naturally found in other plants)
  • Not willing to travel to the University for the study
  • Unable to commit to completing all the sessions in the 10-week intervention study

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm

Intervention / Treatment

Experimental: Coffee Dose-Response Intervention; Participants receive sequential dietary interventions with Coffee A, Coffee B/C, and Tea A across 12 weeks, interspersed with washout periods. Biological samples and dietary records are collected throughout.

Dietary supplement: Coffee A; Week 1: coffee A ≤10 g coffee powder for low dose Week 2: non-coffee consumption (post-consumption kinetics) Week 3: coffee A ≤20 g coffee powder for medium dose Week 4: non-coffee consumption (post-consumption kinetics) Week 5: coffee A ≤40 g coffee powder for high dose Week 6: non-coffee consumption (post-consumption kinetics); Dietary supplement: Coffee B; Week 7: coffee B ≤40 g coffee powder for high dose Week 8: non-coffee consumption (post-consumption kinetics); Dietary supplement: Tea; Week 9: washout Week 10: tea (control) Week 11: non-coffee consumption (post-consumption kinetics)

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Urinary and serum metabolite changes associated with coffee consumption	Urine and serum samples will undergo a combination of targeted and untargeted metabolomic profiling at the Singapore Phenome Centre located at NTU. Briefly, thawed urine, serum, coffee and tea samples will be analysed directly on the UHPLC-TQ-MS. Secondly, to explore potentially novel biomarkers and/or metabolites related to the consumption of the two types of coffee relevant to Singapore (black coffee and coffee with additives), untargeted metabolomics will be conducted on the urine and serum samples.	12week

Collaborators and Investigators

• Sponsor: National University of Singapore

Study record dates

Study Major Dates

• Study Start (Actual): October 1, 2020
• Primary Completion (Actual): December 31, 2022
• Study Completion (Estimated): December 31, 2026

Study Registration Dates

• First Submitted: June 1, 2025
• First Submitted That Met QC Criteria: January 28, 2026
• First Posted (Actual): February 6, 2026

Study Record Updates

• Last Update Posted (Actual): February 6, 2026
• Last Update Submitted That Met QC Criteria: January 28, 2026
• Last Verified: June 1, 2025

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Diet, Food, and Nutrition; Physiological Phenomena; Food and Beverages; Beverages; Plant Preparations; Biological Products; Complex Mixtures; Tea
• Other Study ID Numbers: NUS-IRB-2022-414

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No