GUTPROH: Double-Blind RCT of Probiotic-Herbal Formula for Self-Reported Constipation in Community Adults

The goal of this clinical trial is to evaluate the effects of probiotic combined with or without herbal powder on relieving constipation and improving the gut microbiota in community - dwelling people with a demand for improved bowel movements through human feeding trials, and to explore their potential mechanisms of action.

The main research questions are as follows:

Can the probiotic combined with or without herbal powder significantly increase the frequency of defecation in subjects, and at the same time improve fecal characteristics and defecation conditions? Can the the probiotic combined with or without herbal powder regulate the gut microbiota? What are the biological mechanisms by which the probiotic combined with or without herbal powder improve constipation and gut microbiota function? Researchers will compare experimental group 1 (taking the compound probiotic combined with herbal powder), experimental group 2 (taking probiotics alone) with the placebo control group (taking an identical - looking blank matrix powder) to observe their effects on defecation and the gut microbiota.

The main tasks for participants include:

Taking the compound probiotic combined with herbal powder (experimental group 1), probiotics alone (experimental group 2), or blank matrix powder (placebo control group) as required for 12 weeks.

Recording daily defecation frequency, defecation conditions, fecal characteristics, and daily diet, and reporting any adverse reactions.

Longitudinal monitoring employs serial assessments comprising: 1) physical examinations (mental status/vital signs); 2) laboratory diagnostics (hematology/urinalysis/fecal routine tests, hepatic-renal-metabolic panels); 3) ECG and abdominal ultrasonography; and 4) advanced analyses (gut microbiome sequencing and serum metabolomic profiling via LC/MS/MS).


Eligibility Criteria:
Inclusion Criteria:

* Aged 35 years or older.
* Self - reported good comprehensive physical health status. Have complaints of irregular bowel movement frequency and a need for improved defecation, or have a spontaneous defecation frequency of less than 3 times per week in the 2 weeks before administration, or meet two or more of the following Rome IV criteria for functional constipation (FC): ① \>25% of defecations are difficult; ② \>25% of defecations are dry, hard, or pellet - shaped; ③ \>25% of defecations have a sense of incomplete evacuation; ④ \>25% of defecations have a feeling of anorectal obstruction or blockage; ⑤ \>25% of defecations require manual assistance; ⑥ Fewer than 3 spontaneous defecations per week.
* Provide written informed consent voluntarily before the study and be able to fill out the subject log card and research questionnaire as required by the trial protocol.

Exclusion Criteria:

* Frail elderly people with a score of ≥3 on the FRAIL Frailty Screening Scale.
* Self - reported presence of loose stools.
* Those who have undergone surgery within 30 days, had an acute gastrointestinal disease within 30 days, or have been diagnosed with severe organic diseases causing defecation difficulties (such as colon cancer, intestinal obstruction, inflammatory bowel disease, etc.).
* Patients with severe systemic diseases in the acute phase of cardiovascular, liver, kidney, and hematopoietic systems.
* Patients with symptoms of yin deficiency and internal heat, such as dry mouth, night sweats, restlessness of the five centers (palms, soles, and chest), hard and dry stools with bad breath, red tongue with yellow coating.
* Those who have taken antibiotics within 30 days before the start of the trial.
* Those who have taken probiotics, fermented products, other laxative drugs, or health supplements within 14 days before the start of the trial (i.e., during the wash - out period).
* Those who have not signed the informed consent form. Other situations considered unsuitable for enrollment by the researchers.