Is Sitting Really the New Smoking? How Many Hours of Sitting Is Considered Unhealthy?

Sitting for too long could lead to health issues, such as cancer and heart disease.

Health Risks of Too Much Sitting

According to Naveen Rajpurohit, MD, a cardiologist from Sanford Cardiovascular Institute, too much sitting is a silent killer that is slowly affecting lifestyle.

Prolonged sitting is part of what is known as a sedentary lifestyle. According to the CDC, a sedentary lifestyle that does not involve physical activity could boost one's risk of developing certain conditions, such as heart disease, type 2 diabetes, and certain cancer types.

While physical activity is crucial for health, it has been estimated that, on average, Americans spend around 6.5 to 8 hours each day sitting down. For instance, office workers may spend hours at a time sitting at a desk. Several common pastimes, such as playing computer games or watching television, also involve prolonged sitting.

Too much sitting could affect the body in several ways. For one, a 2018 study shows a link between sitting too much and musculoskeletal discomfort in areas such as shoulders, necks, lower back, lower limbs, buttocks, hands, wrists, and thighs. The study mainly looked into the impacts of sitting for a span of two hours and concluded that levels of discomfort increased as the duration went up. This same study also discovered that prolonged sitting could negatively affect creative abilities for problem solving and perceived mental state.

Moreover, a 2021 study also suggests that sitting too long could impact metabolism after eating. The researchers suggest having regular activity breaks to boost metabolism when a person sits for prolonged periods. The same study also says that sitting for too long could reduce blood flow, especially in the legs. This may result in leg swelling or other consequences.

A 2017 study also links too much sitting with high blood pressure, or hypertension. In the study, 6.3% of office workers had blood pressure levels over 140/90mmHg, which is classified by the American Heart Association as stage 2 hypertension.

How Long Is Too Long?

There is no fast and concrete answer to the number of sitting hours that is considered unhealthy. This may vary from person to person and may also depend on other factors, such as the amount of exercise that a person engages with each day.

According to Just Stand, a charity, these thresholds can shed light on a person's risk of having health issues linked to sitting. The range can be divided into low risk, medium risk, high risk, and very high risk. Low risk involves sitting for under four hours each day; medium risk covers sitting for four to eight hours a day; high risk involves sitting for eight to 11 hours in a day; very high risk refers to sitting for over 11 hours a day.

According to the CDC, engaging in 150 minutes of moderate activity each week could be enough to lower certain health risks linked to a sedentary lifestyle.

Check out more news and information on Medicine & Health in Science Times.