Nattokinase has been confirmed by many experiments to have a thrombolytic effect, but there are currently very few studies on nattokinase's effect on gut microbiota, sleeping status, and age-related cognitive function. Therefore, this study intends to explore the effect of nattokinase on cardiovascular disease risk factors, intestinal microbiota, sleep status and cognitive function in patients with metabolic syndrome risk and sleep disorders. This study will be a double-blind, self-control, placebo, crossover trial, and recruit 70-80 participants over 18 years old, and have risk of metabolic syndrome and sleep disorders. They will be divided into a placebo group and an experimental group. The experimental period was divided into two phases (12 weeks for each) and a 2-week washout period. In the first phase, 2 placebo or nattokinase capsules were given each day (each capsule contained nattokinase 3000FU, 2 capsules per day). After 12 weeks, a 2-week washout period was entered, and the second phase was entered for a crossover trial. At the 0th and 12th weeks of each stage, body position, blood pressure, blood biochemical values, sleep quality questionnaire, and cognitive function questionnaire will be measured, and feces will be collected for bacterial analysis. In addition, to improve the compliance of the trial, it is planned to ask the subjects to return for a follow-up visit in the 6th week of each phase, and to measure the subject's body composition and blood pressure. This study expects that daily supplementation of 2 nattokinase capsules for 12 weeks can improve cardiovascular risk factors, sleep quality and cognitive function, while also maintaining healthy intestinal flora.