Recruiting
Phase 2

Sucralose

Sponsor:

National Institute on Alcohol Abuse and Alcoholism (NIAAA)

Code:

NCT03407079

Conditions

Healthy Volunteers

Overweight

Eligibility Criteria

Sex: Female

Age: 18 - 60

Healthy Volunteers: Accepted

Interventions

Sucralose

Placebo

Study Details

Brief summary:

Background:

Artificial sweeteners like sucralose are found in many foods and drinks. Sucralose might affect hormones and cause health changes.

Objective:

To see if sucralose changes how medicines are absorbed and processed, how hormones are secreted, gut bacteria, and how fat cells are metabolized.

Eligibility:

People ages 18-60 who:

  • Are black or Hispanic
  • Weigh more than 110 pounds
  • Have a body mass index of 25-40
  • Do not have a condition that requires drug treatment

Design:

Participants will be screened with:

  • Medical history
  • Physical exam
  • Blood, heart, and urine tests

Participants must not eat or drink anything with artificial sweeteners throughout the study.

Over 7 days, Participants will answer questions, and give daily urine samples and 1 stool sample. Participants will repeat these throughout the study.

Overnight Visit 1: participants will fast starting the night before. They will get breakfast at the visit. The visit includes:

  • An IV will be placed in the arm. Participants will get 2 tablets of medicines. Blood will be drawn several times over 24 hours.
  • A piece of fat tissue may be taken from the abdomen (biopsy).
  • Participants will have a sweet drink. Blood samples will be taken over 2 hours.

Then participants will be randomly assigned to take either a sucralose capsule or placebo. They will take it twice a day for 2 weeks. They will complete two 24-hour food diaries.

Overnight Visit 2 repeats Visit 1 except the biopsy.

Then participants will take the capsules for another 2 weeks.

Overnight Visit 3 repeats Visit 1.

Participants may be contacted by phone within 4 weeks after they finish.

Conditions

Healthy Volunteers

Overweight

Study ID

NCT03407079

Start date

Apr 5, 2018

Status verified date

Feb 26, 2026

Completion date

Dec 26, 2027

Anticipated

Primary completion date

Dec 26, 2027

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: Female

Age: 18 - 60

Healthy Volunteers: Accepted

  • INCLUSION CRITERIA:

1. Age: between 18 and 60 years
2. Female adults who self-identify as Hispanic and/or Black
3. Body weight greater than 50 kg (110 lb)
4. Body mass index between 25 kg/m\^2 and 40 kg/m\^2
5. Consumption of less than or equal to one 12-ounce beverage sweetened with NNS per month or food equivalent
6. Healthy with no known active medical condition or illness that requires drug treatment
7. Able and willing to consume approximately 4 mg/kg sucralose daily or placebo in form of capsules for

4 weeks

8\. Able and willing to avoid eating grapefruit, parsnips, celery, drinking grapefruit juice or sodas containing quinine (e.g. tonic water) during the study

9\. Able and willing to collect stool specimens

10\. Able and willing to consume digoxin and midazolam during study visits

EXCLUSION CRITERIA:

1. Current use of prescription or non-prescription medication(s), herbal medications and oral contraceptives are also excluded. Certain exceptions are permitted, including vitamins. Other medications may be permitted at the discretion of the investigators.
2. Diabetes (fasting blood glucose of 126 mg/dl or higher, or 2-hour blood glucose of 200 or higher on OGTT)
3. Taken medications that affect blood sugar in the past 3 months or that include antibiotics
4. GI history, at the discretion of the investigators
5. Known allergy, sensitivity, or other contraindication to study procedures
6. ALT or AST more than 1.5 times the upper limit of normal
7. Abnormal thyroid function or abnormal serum electrolytes \& minerals (specifically potassium, calcium, and magnesium)
8. Narrow angle glaucoma or untreated open angle glaucoma
9. Regular use of alcohol (more than 1 drink per day) or drug use
10. History of cardiac abnormalities, especially arrhythmia
11. Unable or unwilling to cooperate with study procedures
12. Psychiatric or cognitive disorder that will, in the opinion of the investigators, limit the subject's ability to provide informed consent, or to comply with study procedures
13. Pregnant, planning to become pregnant or lactating (digoxin and midazolam are Category C and D medications, respectively).

Study Design

Enrollment

150 participants

Anticipated

Allocation

Randomized

Intervention Model

Parallel Assignment

Primary purpose

Other

Interventions and Outcome Measures

Arms

experimental: Study Arm 1

Participants will receive sucralose capsules (approximately 4mg/kg/day) by mouth for 28 days.

placebo comparator: Study Arm 2

Participants will receive placebo capsules by mouth for 28 days.

Interventions

Sucralose

Sucralose is an organochlorine and is approximately 600 times sweeter than sucrose. Participants will receive sucralose (approximately 4mg/kg/day) or placebo by mouth in a capsule for 28 days. This dose corresponds to the amount of sucralose contained in approximately 3 or 4 twelve ounce cans of commercially-available diet soda for a 70 kg adult.

Placebo

Placebo capsules will be taken orally for 28 days

Primary outcome measure

  • To explore the effects of sucralose (approx 4 mg/kg x 28 days) on pharmacokinetics of digoxin and midazolam, which are representative examples of P-gp and CYP3A dependent medications. [ Time Frame: 28 days ]

Central Contacts and Locations

Central contacts

Paule V Joseph, C.R.N.P.

(301) 827-5234paule.joseph@nih.gov

Locations

National Institutes of Health Clinical Center

Recruiting

Bethesda, Maryland, United States, 20892

Contacts

For more information at the NIH Clinical Center contact Office of Patient Recruitment (OPR)

800-411-1222prpl@cc.nih.gov

More Information

Sponsor

National Institute on Alcohol Abuse and Alcoholism (NIAAA)

Last update posted

Sep 1, 2026

Last verified

Feb 26, 2026

Keywords

  • Drug Metabolism
  • Artificial Sweetener
  • P-Glycoprotein
  • Cytochrome P450
  • Microbiome

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-10. This information was provided to ClinicalTrials.gov by National Institute on Alcohol Abuse and Alcoholism (NIAAA) on 2026-09-01.