Clinical Trials Study
Copyright ©The Author(s) 2023. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Clin Cases. Feb 6, 2023; 11(4): 797-808
Published online Feb 6, 2023. doi: 10.12998/wjcc.v11.i4.797
Efficacy of incremental loads of cow’s milk as a treatment for lactose malabsorption in Japan
Matsuri Hasegawa, Kazuko Okada, Satoru Nagata, Shigetaka Sugihara
Matsuri Hasegawa, Shigetaka Sugihara, Department of Pediatrics, Tokyo Women’s Medical University Medical Center East, Arakawa-ku 116-8561, Tokyo, Japan
Kazuko Okada, Department of Pediatrics, Okada Pediatric Clinic, Shinjuku-ku 169-0072, Tokyo, Japan
Satoru Nagata, Department of Pediatrics, Tokyo Women’s Medical University, Shinjuku-ku 162-8666, Tokyo, Japan
Author contributions: Okada K and Nagata S conceptualized and designed the study outline; Hasegawa M and Okada K acquired, analyzed, and interpreted the data, as well as drafted the manuscript; Nagata S advised the interpretation of the data and the critical revision of the manuscript for important intellectual content; Sugihara S obtained funding and supervised the critical revision of the manuscript for important intellectual content; all authors have reviewed and approved the final manuscript.
Supported by Grants of J-milk (Japan Dairy Association).
Institutional review board statement: This work was approved by Tokyo Women’s Medical University Hospital Ethics Committee (approval number 160506).
Clinical trial registration statement: The trial described in this work was registered at under trial number: UMIN 000023298.
Informed consent statement: All study participants, or their legal guardian, provided informed written consent prior to study enrollment.
Conflict-of-interest statement: All the authors declare that they have no conflicts of interest for this article.
Data sharing statement: No additional date are available.
CONSORT 2010 statement: The authors have read the CONSORT 2010 statement, and the manuscript was prepared and revised according to the CONSORT 2010 statement.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See:
Corresponding author: Matsuri Hasegawa, MD, Doctor, Department of Pediatrics, Tokyo Women’s Medical University Medical Center East, 2-1-10, Nishiogu, Arakawa-ku 116-8561, Tokyo, Japan.
Received: October 17, 2022
Peer-review started: October 17, 2022
First decision: November 11, 2022
Revised: December 2, 2022
Accepted: January 5, 2023
Article in press: January 5, 2023
Published online: February 6, 2023
Processing time: 112 Days and 3.5 Hours
Research background

Self-reported lactose intolerance (LI) has been known to have a high prevalence in Asian people. However, there has been no recent report in Japan regarding the prevalence of lactose malabsorption (LM). Some literature shows that colonic adaptation by daily milk or lactose ingestion reduces LI symptoms in patients with LM, but such treatment has not been reported in Japan.

Research motivation

According to the literature from Western countries, patients with LM who underwent milk or lactose loading therapy were required to ingest large volumes of milk within a short period. Applying the same treatment to Japanese people is considered to carry a high risk for abdominal symptoms during the treatment, due to less habitual consumption of milk than Western people. In this study, we implemented an original method of milk loading without affecting daily life of study subjects.

Research objectives

The aim of this study was to examine the efficacy of incremental cow’s milk loading for treating patients with LM.

Research methods

We selected subjects with LI symptoms using a questionnaire, and the selected subjects underwent a 20 g lactose hydrogen breath test (LHBT) for diagnosis of LM. We then conducted the treatment of incremental loads of cow’s milk on the subjects diagnosed with LM, starting from 30 mL and increasing up to 200 mL at 4-7 d intervals. After the treatment, improvement of symptoms and LM diagnostic value of LHBT were investigated. Stool samples pre- and post-treatment were examined for changes in the intestinal microbiota using 16S rRNA sequencing.

Research results

By LHBT, LM was diagnosed in 35 (76%) out of 46 subjects with LI selected using the questionnaire. Improvement of abdominal symptoms after the treatment was seen in 29 (91%) out of 35 subjects with LM. The diagnostic value measured in LHBT before and after the treatment improved in 10 (35%) out of 29 subjects with reduced symptoms, and no change was observed in 16 (55%) subjects. Analysis of fecal microbiota showed a significant increase of Blautia in 7 subjects who became symptom-free after the treatment.

Research conclusions

Incremental loads of cow’s milk that are commercially available is a useful treatment for LM without affecting daily lives of Japanese people.

Research perspectives

The incremental loads of cow’s milk can be widely utilized for LM patients, as well as improve their quality of life. We would like to further verify the efficacy of the same treatment in a longer term study.