The circadian regulation in mammals have been known for a long time. A special group of clock genes, organized in feedback loops, are responsible for the circadian regulation in both the SCN and peripheral organs. The central clock is mainly entrained by the light-dark cycle, while the peripheral ones in organs such as liver and intestine, are more influenced by the feeding-fasting cycles. The coordination of central and peripheral clocks is thought to be essential in the maintenance of physiological homeostasis.This study aim to investigate the association between biological rhythm and metabolism.

Inclusion Criteria:

• Male or female；
• Aged of 18 to 30 years old;

Exclusion Criteria:

• Presence of pituitary/hypothalamic disorders, polycystic ovarian syndrome， thyroid disorders, hypertension, malignant tumor, cardiac insufficiency，hepatic or renal insufficiency, gastrointestinal disorders and acute infection;
• Receiving psychotropic or hormonal medications including hormonal contraception and hormone therapies;
• Taking lipid-lowering agents or hypoglycemic agents and other drugs that known to influence cardiovascular health;
• Pregnancy or lactation women;
• Obviously poor compliance.

Adults aged of 18 to 30 years old.