Pharmacokinetic Assessment of Betaine Supplementation in Lactating Mothers (BetMilkII)

In this study, the investigators will evaluate the dynamics of betaine excretion into breast milk following supplementation. Milk betaine concentrations will be measured at baseline (0 hours) and at 3, 6, and 12 hours after the first dose of 400 milligrams (mg) betaine to assess the short-term impact of maternal betaine supplementation on milk betaine concentration and related metabolites during 12 hours after intake. These measurements will be repeated after one week of daily supplementation with this low dose. Subsequently, the same protocol will be conducted using a higher dose (1.5 gram/day) for one additional week to compare milk betaine concentration and related metabolites before and after the supplementation period at two different doses. Depending on the outcomes, the investigators will also analyze milk macronutrient composition and explore untargeted metabolomic changes.

Study Overview

• Status: Active, not recruiting
• Conditions: Breast Milk Fortifier Supplements
• Intervention / Treatment: Dietary supplement: Betaine supplement

• Study Type: Interventional
• Enrollment (Estimated): 10
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Spain
  • Barcelona
    • Barcelona, Barcelona, Spain, 08950
      • Hospital Sant Joan de Déu

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

• Exclusively breastfeeding
• Infant age between 2 and 5 months

Exclusion Criteria:

• Multiple pregnancy
• Infant weight at recruitment < -1 standard deviations (SD)
• Cystathionine Beta-Synthase (CBS) deficiency (inherited disease)

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: Betaine Supplementation (Sequential Low and High Dose); Participants will receive oral betaine supplementation at a low dose (400 milligrams/day) for one week, followed by a high dose (1.5 grams/day) for one additional week. Milk samples will be collected at baseline and at multiple time points to evaluate betaine dynamics, accumulation, and associated metabolic changes.	Dietary supplement: Betaine supplement; Oral betaine supplementation will be administered to lactating women. Participants will receive a dose of 400 milligrams/day for 1 week, followed by 1.5 grams/day for an additional week.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Incidence of Treatment-Emergent Adverse Events (Safety and Tolerability)	Treatment safety and tolerability will be evaluated by assessing differences in the incidence of potential adverse events, focusing on gastrointestinal symptoms.	Baseline, 1 week, 2 weeks
Change in betaine concentration in human milk	Variation in betaine levels in breast milk measured at baseline (0 hours) and at 3 hours, 6 hours, and 12 hours after taking supplement	Baseline (0, 3, 6, 12 hours), 1 week (0, 3, 6, 12 hours), 2 weeks (0, 3, 6, 12 hours)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Changes in the one-carbon metabolite profile of breast milk	Milk samples will be analyzed by liquid chromatography-mass spectrometry to quantify betaine-related metabolites, including dimethylglycine, methionine, S-adenosylmethionine, S-adenosylhomocysteine, cystathionine, choline, homocysteine, methyl folate, and folic acid at the different time-points.	Baseline (0, 3, 6, 12 hours), 1 week (0, 3, 6, 12 hours), 2 weeks (0, 3, 6, 12 hours)

Collaborators and Investigators

• Sponsor: Fundació Sant Joan de Déu

Study record dates

Study Major Dates

• Study Start (Actual): October 30, 2025
• Primary Completion (Estimated): June 1, 2026
• Study Completion (Estimated): June 1, 2026

Study Registration Dates

• First Submitted: November 14, 2025
• First Submitted That Met QC Criteria: November 19, 2025
• First Posted (Actual): November 24, 2025

Study Record Updates

• Last Update Posted (Actual): March 20, 2026
• Last Update Submitted That Met QC Criteria: March 19, 2026
• Last Verified: March 1, 2026

More Information

Terms related to this study

• Keywords: Pharmacokinetics; Breast milk; Betaine
• Other Study ID Numbers: PIC-142-25 (Other Identifier: Hospital Sant Joan de Déu)

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