For many of us, the average day involves a lot of time sitting. In fact, the Centers for Disease Control and Prevention (CDC) estimates that Americans spend an average of 6.5 to 8 hours a day sitting. This type of sedentary lifestyle has led to several leading health experts to declare that sitting is the new smoking, meaning that the dangers of spending too much time sitting are having serious effects on overall health.
A National Health Survey showed that nearly one in four people aged 18-64 years met the physical activity guidelines. Nearly half (49%) of employed people aged 18-64 years described their day at work as mostly sitting. Physical inactivity contributes to over three million preventable deaths worldwide each year (that’s six percent of all deaths). It is the fourth leading cause of death due to non-communicable diseases. It’s also the cause of 21–25% of breast and colon cancers, 27% of diabetes cases, and around 30% of ischemic heart disease.
The CDC suggests that sedentary lifestyles with no physical activity increase a person’s risk of developing health conditions, such as heart disease, type 2 diabetes, and some types of cancer.
Sitting all day without adequate physical activity can also impact a person’s sleep quality, mental health, physical and cognitive abilities and bone health.
Research has linked sitting for long periods of time with a number of health concerns. Issues include obesity and a cluster of conditions such as increased blood pressure, high blood sugar, excess body fat around the waist and unhealthy cholesterol levels that make up metabolic syndrome. Too much sitting overall and prolonged periods of sitting also seem to increase the risk of death from cardiovascular disease and cancer. You may also be more likely to get colon, endometrial, or lung cancer.
Researchers analyzed 13 studies of sitting time and activity levels. They found that those who sat for more than eight hours a day with no physical activity had a risk of dying like that posed by obesity and smoking.
Research suggests that people who spend more time sitting have a 112% higher risk of diabetes. While it isn’t clear why your odds of diabetes rise, doctors think sitting may change the way your body reacts to insulin. If you spend a lot of time sitting, digestion is not as efficient, so you retain those fats and sugars as fat in your body. You are also more likely to be overweight or obese.
Sit for too long and your venous system is affected as blood can pool in your legs which puts added pressure in your veins. They could swell, twist, or bulge which is known as varicose veins. You may also see spider veins, bundles of broken blood vessels nearby. Deep vein thrombosis (DVT) is a clot that forms in your leg, often because you sit still for too long. It can be serious if the clot breaks free and lodges in your lung.
Sitting for long periods has been linked to heart disease. One study found that men who watch more than 23 hours of television a week have a 64% higher risk of dying from cardiovascular disease than men who only watch 11 hours of television a week. Some experts say that people who are inactive and sit for long periods have a 147% higher risk of suffering a heart attack or stroke.
Sitting for long periods can lead to weakening and wasting away of the large leg and gluteal muscles. These large muscles are important for walking and for stabilizing you. Your hips and back will also not support you as well if you sit for long periods. Sitting causes your hip flexor muscles to shorten, which can lead to problems with your hip joints.
While scientist can’t quite explain the links between sitting and mental health as well as the links between sitting and physical health, they do know that the risk of both anxiety and depression is higher in people that sit more. This might be because people who spend a lot of time sitting are missing the positive effects of physical activity and fitness. Also, it can affect your memory as if you sit too much, your brain could look just like that of someone with dementia.
While the CDC considers 150 minutes of moderate activity per week adequate to lower the risk of some health conditions associated with a sedentary lifestyle there is no hard and fast answer to how many hours of sitting is unhealthy. It is different for everyone and can depend on factors such as how much exercise a person does each day. Overall, research seems to point to the fact that less sitting and more moving contribute to better health. Sitting is best mitigated by frequent movement, even if it’s only done for brief periods of time. Look for ways to be active throughout the day and shoot for the recommend 50:50 sit to stand ratio.
If you’re new to physical activity, or if you have a health condition, West Tennessee Medical Group has providers who can help and are close to home. Click here to find a doctor near you and schedule an appointment.
