Inclusion Criteria:  Participants reside in Hangzhou Participants have no traveling plans within 3 months  Exclusion Criteria:  Refusing or unable to give informed consent Participants with chronic gastrointestinal diseases and take daily relevant medications Participants with metabolic diseases including diabetes, hypertension and cardiovascular diseases (CVD) Participants with craniocerebral trauma, cancer, liver disease, kidney disease, or other critical illness, or history of operation or medication Participants with bulimia nervosa, post-traumatic stress disorder (PTSD), chronic anxiety and depression or other critical neuronal disorder or history of relevant medication Being or to be pregnant or lactating. Participants with history of alcohol or drug addiction, or smoke above 15 cigarettes per day Concurrently participating other clinical trials.