The purpose of this study is to thoroughly investigate how the interaction between black rice and human gut microbiota affects metabolic diseases, this study will recruit patients with Metabolic Syndrome (MS) and provide them with dietary supplementation of black rice (50 g/day) for 3 months to observe its effect on the development of MS. The focuses of this project are to elucidate how black rice consumption affects the composition and metabolism of intestinal bacteria as well as the development of MS, and to further analyze whether the changes in intestinal bacteria are associated with the changes in MS improvements.

Inclusion Criteria:

• individuals meeting at least 3 of the following 5 criteria will be chosen:
• abdominal obesity: using the waist standard for Asians: waist≥90 for male and ≥80 for female
• high blood sugar: fasting plasma glucose≥5.6mmol/L (100mg/d L) or individuals diagnosed with diabetes and being treated
• hypertension: systolic blood pressure≥130 mm Hg or diastolic blood pressure≥85 mm Hg or individuals diagnosed with hypertension and being treated
• dyslipidemia: fasting total triglycerides≥1.70 mmol/L(150 mg/d L) or individuals undergoing lipid-lowering therapy
• fasting plasma high-density lipoprotein cholesterol<1.03mmol/L (40mg/dL) for male or <1.3mmol/L (50mg/dL) for female.

Exclusion Criteria:

• having current or former cardiovascular disease, including coronary heart disease (e.g., angina pectoris, myocardial infarction, coronary revascularization, abnormal Q waves in ECG), stroke (e.g., congestive, hemorrhagic, or transient ischemic stroke), and intermittent claudication caused by peripheral arterial diseases;
• severe clinical conditions that may compromise patients' participation in experiments, e.g., digestive diseases leading to inability to maintain black rice uptake, patients receiving parenteral nutrition supply, malignancies in progress, and mental illness;
• immunodeficiency disease or AIDS, chronic inflammation conditions
• drug abuse or alcoholism (>80g/d).