For many people, office work involves extended periods of time at their desk. For some, it can be all day.

Despite the growing availability of ergonomic products and workplace offerings like flexible gym hours, scientists believe many desk jockeys will have already done lasting damage to their bodies as a result of sitting down all day.

According to Peter T. Katzmarzyk, Ph.D.:

“Even within physically active individuals, there was a strong association between sitting and risk of mortality… This is an important observation because it suggests that high amounts of sitting cannot be compensated for with occasional leisure time physical activity even if the amount exceeds the current minimum physical activity recommendations.”

It’s hard to imagine such a simple, unconscious act can bet so detrimental to our heath but in fact there are many devastating implications from working at a desk.

Here are 11 adverse effects on the body that can occur from sitting at your desk for too long.

1. Low energy expenditure
Role of Low Energy Expenditure and Sitting in Obesity, Metabolic Syndrome, Type 2 Diabetes, and Cardiovascular Disease
Sitting at your desk for too long reduces your non-exercise activity thermogenesis is generally a much greater component of total energy expenditure than exercise.

2. Slower metabolism
Sitting Time and All-Cause Mortality Risk in 222 497 Australian Adults
The decreased muscle contractions that occurs with prolonged, immobile sitting slows the clearance of fat from the blood stream and decreases the effect of insulin.

3. Compromised posture 
Sitting bio-mechanics
Sitting causes the pelvis to rotate backward and puts pressure on the lumbar discs. This position forces the head forward and cause the shoulders to curve to compensate for the weight transfer.

4. Back and spine injuries
The biomechanics of low back injury: Implications on current practice in industry and the clinic
Prolonged, static loading of tissues over time puts undue pressure on the low back and stress the surrounding muscles and joints.

5. Reduced social skills
Internet paradox: A social technology that reduces social involvement and psychological well-being?
Interaction limited to communication over the internet is associated causes a decline in social involvement and psychological well-being.

6. Loneliness or depression
Internet paradox: A social technology that reduces social involvement and psychological well-being?
When the computer is used as the single form of communication, the size of a person’s social circle is believed to decline, and and feelings of depression and loneliness increase. Being stuck at your desk also means you’re probably not getting outside enough. This lack of sunshine can cause person to become deficient in vitamin D and ultimately lead to depression.

7. Metabolic Syndrome
Role of Low Energy Expenditure and Sitting in Obesity, Metabolic Syndrome, Type 2 Diabetes, and Cardiovascular Disease

8. Chronic Pain
Ergonomics of posture—Review of various problems of standing and sitting posture
Inadequate sitting postures, associated with long periods of sitting at a desk, provoke excessive increases of lower back pressure. These somatic pains can become the symptoms of chronic diseases.

9. Rheumatic disorders
Ergonomics of posture—Review of various problems of standing and sitting posture
Some rheumatic diseases like osteoarthritis are the result of “wear and tear” to the joints, like that of excessive amounts of sitting.

10. Obesity
Sitting Time and All-Cause Mortality Risk in 222 497 Australian Adults
Sitting at a desk reduces a person’s energy expenditure because the body’s major muscle groups aren’t being utilized and calorie burning is minimized. Over an extended period of time this can lead to weight gain and in severe cases obesity.

11. Diabetes
Sitting Time and All-Cause Mortality Risk in 222 497 Australian Adults
Sitting at a desk all day impairs the body’s ability to handle blood sugar, causing a reduced sensitivity to the hormone insulin, which helps carry glucose from the blood into cells where it can be used for energy.

12. Cancer
Occupational physical activity and the incidence of cancer of the breast, corpus uteri, and ovary in Shanghai.
Low physical activity occupations have an increased incidence of cancer. A study found women’s chances of developing breast, corpus uteri, and ovary cancer were heighten if working in a sedentary job.

13. Your risk of heart disease has increased by up to 64%
Sedentary behaviors increase risk of cardiovascular disease mortality in men

14. All-cause mortality is adversely effected from too much sitting, independent of physical activity.
Sitting Time and All-Cause Mortality Risk in 222 497 Australian Adults
A study found prolonged sitting time was responsible for 6.9% of deaths. The association between sitting and all-cause mortality remains consistent across women and men, age groups, weight, health and physical activity levels.

Worried? Here are tips from James A. Levine, M.D., Ph.D. of the Mayo Clinic on how to sit less and move more to live better.

• Periodically move around in your seat.
• Stand while talking on the phone or eating lunch.
• Use a stand up desk.
• Have organized breaks throughout the day.
• Walk laps with your colleagues rather than gathering in a conference room for meetings.
• Position your work surface above a treadmill so that you can be in motion throughout the day.