A prospective, randomized, blinded, placebo-controlled clinical study on the effects of Lactobacillus rhamnosus LRa05 intervention on growth and development, allergic disease incidence, and immune function in infants and young children
Promoting the growth and development of healthy infants and young children of different age groups, enhancing their immune function, and reducing the incidence of common diseases.
This study is a randomized controlled blind intervention study. A random allocation table was generated by a biostatistician using statistical software on a computer. A total of 440 subjects were included, with 120 subjects in each of the 0-6 months, 6-12 months, and 12-36 months age groups. Additionally, an 80-subject breastfed control group for the 0-6 months age group was added. The random allocation table generated by the biostatistician was used for coding to meet the requirements of randomization. Subjects were enrolled strictly in the order of their random numbers and no changes were allowed. Each subject was randomly assigned to the probiotic intervention group, the placebo control group, or the breastfed control group. The groups were divided as follows: 1) Probiotic intervention group: One packet per day (containing 1×1010 CFU of LRa05 strain per packet), starting from the day of using the probiotic product and continuing for 3 months, followed by a 3-month follow-up. 2) Placebo control group: One packet per day (containing maltodextrin, without LRa05 strain), starting from the day of using the placebo product and continuing for 3 months, followed by a 3-month follow-up. 3) Breastfed control group: No intervention measures were taken, only breastfed.
Current key exclusion criteria as of 02/07/2026: Exclusive breastfeeding group: 1. Healthy infants and toddlers born at term (37-42 weeks of gestation) who are exclusively breastfed, with a birth weight of at least 2500g but less than 4000g, and no gender restrictions 2. The mother has no diagnosed metabolic diseases, such as diabetes, and no infectious diseases, such as hepatitis B or HIV 3. The age at inclusion is less than 7 months 4. The parents or main guardians of the infants and toddlers agree to collect fecal samples from the infants and toddlers during the study period 5. There are no diagnosed allergic diseases by a clinical physician at the time of inclusion (including but not limited to eczema, asthma, allergic proctocolitis, allergic rhinitis, hay fever, etc.) 6. The infants and toddlers have established a health record at the local maternal and child health hospital's pediatric health department and receive regular physical examinations and feeding advice and guidance from pediatric health doctors 7. The family members or main guardians promise not to add any additional probiotic products (including formula milk powder containing probiotics) to the infants and toddlers during the study period 8. The guardians of the included subjects agree to participate in this interventional study and sign a written informed consent form and are able to understand and fill out the infant and toddler diaries and other forms as required Formula feeding group: 1. Healthy infants and toddlers born at term (37-42 weeks of gestation) who are formula-fed, with a birth weight of at least 2500g but less than 4000g, and no gender restrictions 2. The mother has no diagnosed metabolic diseases, such as diabetes, and no infectious diseases, such as hepatitis B or HIV 3. The age at inclusion is 0-6 months, 7-12 months, or 13-36 months 4. The parents or main guardians of the infants and toddlers agree to collect fecal samples from the infants and toddlers during the study period
Exclusive breastfeeding control group: 1. Infants and young children with a history of asphyxia at birth or a history of NICU hospitalization 2. Infants and young children with birth defects or congenital abnormalities 3. Infants and young children whose mothers had high-risk obstetric factors during pregnancy, such as pregnancy-induced hypertension syndrome, preeclampsia and eclampsia, gestational diabetes, and cholestasis of pregnancy, as well as a history of alcohol abuse or drug abuse 4. Infants and young children who had used antibiotics within two weeks before enrollment 5. Infants and young children who had diseases that definitely affected growth and development within one month before enrollment (such as pneumonia, severe diarrhea, severe constipation, severe cow's milk protein allergy, malnutrition, gastrointestinal surgery, etc., severe congenital heart disease, epilepsy, cerebral palsy, mental retardation and other neurological diseases, as well as definite genetic metabolic diseases, chromosomal diseases, and genetic diseases) 6. Infants and young children with severe primary diseases of important organs or systems such as the heart, liver, kidneys, and hematopoietic system 7. Infants and young children who had used any experimental drugs or participated in other clinical studies within three months before screening (for infants and young children under 3 months of age, the time from birth to enrollment is calculated) 8. Infants and young children who had taken probiotic products within one month before enrollment (for infants and young children under 1 month of age, the time from birth to enrollment is calculated) 9. Infants and young children who had used drugs that suppressed immune function (such as glucocorticoids and immunosuppressants) before enrollment 10. Infants and young children who were allergic to the known components of the probiotic product 11. Children with malnutrition requiring hospitalization 12. Other reasons considered by the resea