Participants
infectious diseases, diarrhea, constipation
INFECTIOUS DISEASES, STOMACH ULCERS, HYPOTHYROIDISM, SUBCLINICAL HYPOTHYROIDISM, GASTROINTESTINAL DISEASES
The target population was adults with hypothyroidism. Inclusion criteria were: Women or men, 25–65 years old (protocol amendment), with subclinical hypothyroidism (elevated TSH level and a normal or low free T4 level) for at least 6 months (protocol amendment), and BMI less than 35 who were being treated by levothyroxine. Exclusion criteria were: Lactating or pregnancy; History of taking probiotic or synbiotic supplements in the last three months; Smoking or alcohol consumption; Taking appetite suppressants such as antibiotics; Use of antibiotics and any medications that interact with synbiotics; Gastrointestinal diseases such as stomach ulcers, diarrhea or constipation etc. for three months before or during the intervention; Unwillingness to continue cooperation, and non-compliance during the intervention. Participants were also excluded in case of catching infectious diseases such as Covid-19, occurrence of pregnancy, and undergoing surgery during the study period.