According to the latest statistics, the prevalence of erectile dysfunction (ED) in China is about 31%, is ED just ED?64% of ED patients have at least one concurrent disease! Erectile dysfunction is often associated with many chronic diseases (e.g. psychosomatic disorders, diabetes, hypertension, prostate enlargement, etc.), and there is growing evidence that erectile dysfunction is more likely to be closely related to metabolic syndrome. First of all, the definition of metabolic syndrome (MS): a state in which a variety of metabolic risk factors such as hyperglycemia, hypertension, obesity and dyslipidemia are clustered in the human body, the diagnostic criteria for metabolic syndrome in Chinese people: those who meet three or all of the following four components: 1, overweight or obesity Body Mass Index (BMI) ≥ 25,0kg/m2; (weight/height squared). 2, Hyperglycemia Fasting blood glucose: ≥110mg/dl (6,1mmol/l) and/or post glycemic load blood glucose ≥140mg/dl (7,8mmol/l); and/or those who have been diagnosed and treated for diabetes mellitus. 3.Hypertension systolic/diastolic blood pressure ≥140/90mmhg, and/or those who have been diagnosed and treated for hypertension. 4, dyslipidemia: fasting total cholesterol tg ≥ 1,70mmol/l (150mg/dl); and/or fasting blood HDL-c: male < 0,9mmol/l (35mg/dl), female < 1,0mmol/l (39mg/dl). High-risk groups for the development of metabolic syndrome: 1. ≥40 years of age; 2. 1 or 2 components of metabolic syndrome that do not yet meet the diagnostic criteria; 3. cardiovascular disease, nonalcoholic fatty liver, gout, polycystic ovary syndrome and various types of lipoatrophy; 4. obesity, type 2 diabetes mellitus, hypertension, dyslipidemia, especially in multiple combinations or a family history of metabolic syndrome; 5. a family history of cardiovascular disease; MS may be associated with a family history of cardiovascular disease. A family history of cardiovascular disease; MS can lead to serious cardiovascular disease and complications and is now a global health problem. It is a group of diseases, rather than a separate disease, with insulin resistance and obesity as the underlying alterations. The pathogenesis and pathophysiological characteristics are not fully equivalent to simple obesity, diabetes, dyslipidemia and essential hypertension, which has both the clinical manifestations of the above diseases and some of its own characteristics, more complex than a single disease. A high-fat diet combined with a lack of exercise habits cause obesity and insulin resistance (R) based changes in diabetes mellitus, hypertension and lipid metabolism abnormalities syndrome, which ultimately leads to the development of atherosclerotic disease. These are not the main focus of this article, you can read related articles if you are interested. What we need to introduce is the relationship between MS and ED. According to the aforementioned, ED patients have multiple co-morbidities at the same time, and the proportion of ED patients with multiple co-morbidities is significantly higher compared to those without ED. Let's understand the correlation study between MS and ED, first of all, about 70% of male patients with MS are in co-morbidities with ED, such as coronary artery disease, hypertriglyceridemia and cholesterolemia, hypertension, diabetes mellitus and so on. Diabetes mellitus, hypertension, obesity, and dyslipidemia can respectively increase the risk of ED and aggravate the degree of ED; MS is an aggregation of many of the above risk factors, which makes the effect of MS on ED more prominent; therefore, MS and ED share common risk factors; and the elements contained in MS all have a relationship with free testosterone. There is growing evidence that in the vast majority of patients, ED is a vascular disease. Endothelial cell dysfunction is the initial step in the atherosclerotic process involving the narrowing of many blood vessels, including the cavernous arteries of the penis, cavernous sinuses, and coronary circulation. Impairment of vascular endothelial function is a common factor in ED and ischemic heart disease, and diabetes, hypertension, obesity, and dyslipidemia are very important among the causes of endothelial damage. Various studies have shown a correlation between MS and ED, with hypertension, diabetes, obesity, and lipid metabolism disorders being associated with an increased likelihood of ED with a longer history of the disease, and the presence of ED serving as a warning sign of cardiovascular disease. The presence of ED can be ameliorated by a series of treatments for MS, and low-dose PDE5i (sildenafil, tadalafil, vardenafil, etc.) therapy may improve oxygen and blood supply to penile cavernous smooth muscle, improve vascular endothelial function, reduce fibrosis and apoptosis of cavernous smooth muscle cells, and increase nocturnal erections; - hopefully, curing psychological ED and mild organic ED and restoring spontaneous erections. It can also be expected to improve ischemic heart disease through endothelial repair. To summarize, both MS and ED are two major killers affecting men's health. Healthy lifestyles such as moderate exercise, smoking cessation and moderate alcohol consumption, as well as control of body weight, blood glucose, and blood pressure can lead to the improvement of the conditions of both, bringing happiness and sexual well-being. And the safe use of PDE5i (sildenafil, tadenafil, vardenafil, etc.) can bring higher quality of life.