The metabolic syndrome is featured by obesity, dyslipidemia and insulin resistance, additionally associated with inflammatory and fibrinolytic dysfunctions, all of which are risk factors of cardiovascular diseases and type 2 diabetes. The lifestyle factors that could cause and aggravate the metabolic syndrome are physical inactivity, calorie-dense diet, habitual alcohol drinking and smoking, and psychosocial stress. Energy excess along with a lot of saturated fat, i.e. more fast food and sugar-containing drinks, and sedentary lifestyle like television viewing are contributing to the epidemic of obesity. The significance of lifestyle from birth to adulthood will be reviewed in the context of the metabolic syndrome, as well as the background and environment in which the convenient lifestyle spread far and wide among us.