Effects of Caffeinated Beverages on Well-being

A Randomized, Decentralized, Crossover, Open-Label Trial to Assess Subjective and Physiological Responses to Consumption of Caffeinated Beverages in Healthy Adults With a Caffeine Routine

This study will evaluate post-beverage subjective caffeine responses and physiological responses to caffeinated beverages in generally healthy adults.

Study Overview

• Status: Recruiting
• Conditions: Healthy; Caffeine; Beverage Intake
• Intervention / Treatment: Other: Participants' typical caffeinated beverage; Other: Test caffeinated beverage

Detailed Description

This will evaluate post-beverage subjective caffeine responses using visual analog scale questionnaires, mood, quality of life, and physiological responses to caffeine beverages compared to participants' habitual caffeine beverage intake in generally healthy adults.

• Study Type: Interventional
• Enrollment (Estimated): 150
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: VP Product Innovation, Guayaki Sustainable Rainforest Products; Phone Number: 609-799-6067; Email: info@guayaki.com
• Study Contact Backup: Name: Alethios, Inc.; Phone Number: 650-206-8006; Email: support@alethios.com

Study Locations

• United States
  • California
    • San Francisco, California, United States, 94109
      • Recruiting
      • Alethios, Inc.
      • Contact: Alethios, Inc.; Phone Number: 650-206-8006; Email: support@alethios.com

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

1. Males or females, ≥18 to ≤55 years of age
2. BMI ≥18.5 and <29.9 kg/m2
3. Generally good health
4. Participant currently and consistently has a caffeine routine
5. Participant is willing to substitute their current caffeine routine for the test beverage daily
6. Participant has never consumed the test beverage or similar products
7. Participant currently owns a wearable and is willing to use and connect the wearable device
8. Willing to use personal smart phone, tablet, or personal computer with stable internet connection
9. Willing and able to comply with all study procedures
10. Willing to adhere to all study procedures, including lifestyle considerations and sign forms providing informed consent to participate in the study

Exclusion Criteria:

1. History or presence, on the basis of the health history, of clinically important condition or disease states
2. Is currently following, or planning to be on, a weight loss regimen
3. Weight loss or gain >4.5 kg
4. History of gastrointestinal surgery for weight reducing purposes or gastrointestinal (GI) conditions
5. History of an eating disorder (e.g., anorexia nervosa or bulimia nervosa, binge eating) at the discretion of the Clinical Investigator.
6. History of unconventional sleep patterns (e.g., night shift) or diagnosed sleep disorder
7. Use of tobacco/nicotine products
8. Use of hemp/marijuana products
9. Unstable use of any prescription medication
10. Use of any medications(s) or dietary supplement(s), containing caffeine, or interacting with caffeine
11. Recent history of alcohol or substance abuse
12. Exposed to any non-registered drug product
13. Self-report of hypertension/high blood pressure without use of hypertensive medications
14. Any known allergy or intolerance to any ingredients contained in the study product
15. Any signs or symptoms of active infection of clinical relevance
16. History or presence of cancer, except for non-melanoma skin cancer
17. History of any major trauma or major surgical event
18. Female who is pregnant, planning to be pregnant during the study period, lactating
19. An employee, close relative of an employee, or participant who has a financial interest in Sponsor company or any other caffeine beverage company.
20. Any condition the Investigator believes would interfere with the participant's ability to provide informed consent or comply with the study protocol
21. A clinically significant medical condition that is affected by caffeine

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Other
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Other: Test caffeinated beverage followed by participants' typical caffeinated beverage	Other: Participants' typical caffeinated beverage; Participants will consume the caffeinated beverage they typically consume.; Other: Test caffeinated beverage; Participants will consume a test beverage that contains caffeine.
Other: Participants' typical caffeinated beverage followed by test caffeinated beverage	Other: Participants' typical caffeinated beverage; Participants will consume the caffeinated beverage they typically consume.; Other: Test caffeinated beverage; Participants will consume a test beverage that contains caffeine.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Subjective caffeine visual analog scales	Participants will rate how they feel on a horizontal line. Lines will be flanked with perceived feelings. Scores range from 0-100, where a higher score indicates increase in that feeling.	After 5 days of daily consumption

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Subjective caffeine visual analog scales	Participants will rate how they feel on a horizontal line. Lines will be flanked with perceived feelings. Scores range from 0-100, where a higher score indicates increase in that feeling.	Up to 5 hours after beverage consumption
Subjective quality of life ratings	Participants will rate how they feel using a Likert scale from 0-5. Where higher score indicate higher frequency in that feeling.	After 5 days of daily consumption

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Physiological responses - Heart rate	Data collected by wearables	Up to 5 hours post-beverage consumption and after 5 days of daily beverage consumption
Subjective beverage experience ratings	Participants will rate how they feel on a horizontal line. Lines will be flanked with perceived feelings. Scores range from 0-100, where a higher score indicates increase in that feeling.	After 5 days of daily consumption
Physiological response - Sleep	Data collected by wearables	Up to 5 hours post-beverage consumption and after 5 days of daily beverage consumption
Physiological responses - Activity	Data collected by wearables	Up to 5 hours post-beverage consumption and after 5 days of daily beverage consumption

Collaborators and Investigators

• Sponsor: GUAYAKI SUSTAINABLE RAINFOREST PRODUCTS, INC.
• Collaborators: Nlumn LLC; Alethios, Inc.
• Investigators: Principal Investigator: Kristin Nieman, PhD, Nlumn LLC

Study record dates

Study Major Dates

• Study Start (Actual): November 3, 2025
• Primary Completion (Estimated): April 1, 2026
• Study Completion (Estimated): April 1, 2026

Study Registration Dates

• First Submitted: December 26, 2025
• First Submitted That Met QC Criteria: January 13, 2026
• First Posted (Actual): January 22, 2026

Study Record Updates

• Last Update Posted (Actual): January 22, 2026
• Last Update Submitted That Met QC Criteria: January 13, 2026
• Last Verified: December 1, 2025

More Information

Terms related to this study

• Keywords: Caffeine beverages in health and well-being
• Other Study ID Numbers: NL-2502

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