Sedentary lifestyle is a lifestyle type, in which one is physically inactive and does little or no physical movement and or exercise. A person living a sedentary lifestyle is often sitting or lying down while engaged in an activity like socializing, watching TV, playing video games, reading or using a mobile phone or computer for much of the day. A sedentary lifestyle contributes to poor health quality, diseases as well as many preventable causes of death. Sitting time is a common measure of a sedentary lifestyle. A global review representing 47% of the global adult population found that the average person sits down for 4.7 to 6.5 hours a day with the average going up every year. The CDC found that 25.3% of all American adults are physically inactive. Screen time is a term for the amount of time a person spends looking at a screen such as a television, computer monitor, or mobile device. Excessive screen time is linked to negative health consequences. Definition Sedentary behavior is not the same as physical inactivity: sedentary behavior is defined as "any waking behavior characterized by an energy expenditure less than or equal to 1.5 metabolic equivalents (METs), while in a sitting, reclining or lying posture". Spending most waking hours sitting does not necessarily mean that an individual is sedentary, though sitting and lying down most frequently are sedentary behaviors. Esmonde-White defines a sedentary lifestyle as a lifestyle that involves "longer than six hours a day" of sedentary behavior. Health effects Effects of a sedentary work life or lifestyle can be either direct or indirect. One of the most prominent direct effect of a sedentary lifestyle is an increased BMI leading to obesity. A lack of physical activity is one of the leading causes of preventable death worldwide. At least 300,000 premature deaths, and $90 billion in direct healthcare costs are caused by obesity and sedentary lifestyle per year in the US alone. The risk is higher among those that sit still more than per day. It is shown to be a risk factor on its own independent of hard exercise and BMI. People that sit still more than per day have a higher risk than those that sit fewer than per day. However, those that exercise at least per week are as healthy as those that sit fewer than per day. Indirectly, an increased BMI due to a sedentary lifestyle can