Experts reveal sitting for 7 hours daily shortens lifespan

Many office workers have the habit of sitting for long periods, but research shows that prolonged sitting can quietly steal your life. Sitting for seven hours daily shortens average life expectancy by 28 days per year. Experts warn it also significantly increases the risk of dementia, diabetes, and cardiovascular disease, creating a health crisis born from sitting.

3 Deadly Sitting Postures that Easily Harm the Body

According to a report by Japanese media, a US study in May this year showed that prolonged sitting increases the risk of early-onset dementia. The World Health Organization (WHO) points out that sitting for long periods also increases the incidence of type 2 diabetes, cardiovascular disease, and cancer, while shortening lifespan. 

An estimate from Japan's pharmaceutical industry suggests that for those who sit for seven hours daily, lifespan is shortened by two hours and 34 minutes each day, potentially resulting in a loss of about 28 days of life per year.

4 Major Causes of Lifespan Shortening from Prolonged Sitting

Neurosurgeon Dr. Ayumu Okumura and neurologist Dr. Toshinori Kato explained in an interview the following reasons why prolonged sitting shortens life.

1. Insufficient Blood Flow to the Brain
The legs and buttocks comprise about 70 percent of the body's muscles, acting like a pump to circulate blood throughout the body. Prolonged sitting slows this pumping function, causing blood to stagnate in the lower body and reducing blood flow to the brain, which lowers brain activity.

2. Decreased Metabolism
Compared to standing, sitting for long periods decreases metabolism by 20 percent, making it easier to develop diabetes and metabolic syndrome. It also makes blood clots more likely to form in the legs. If a clot travels to the pulmonary artery and blocks lung blood vessels, it increases the risk of economy class syndrome.

3. Reduced Brain Activity
Moving the legs stimulates the motor and thinking areas in the brain's frontal lobe. Sitting for long periods leads to a loss of spontaneity, preventing the brain from functioning properly. If you sit for a long time while staring at your phone, brain activity that should be active gradually decreases.

4. Less Sun Exposure
Increased time spent sitting indoors reduces opportunities for sun exposure, making depression – considered a risk factor for dementia – more likely.

3 Dangerous Sitting Postures That Worsen Lower Back Pain

Because you sit for long periods, paying attention to posture is even more crucial. Maintaining the same posture for more than 20-30 minutes is not good. Among various sitting postures, experts highlight the following three as the most harmful and burdensome on the lower back:

• Perching/Sitting Shallow: Sitting on the edge of the chair.
• Slanting/Sitting Asymmetrically: Sitting with uneven weight distribution.
• Leaning/Reclining Sit: Leaning the body against the backrest with elbows propped on the armrests.

4 Major Countermeasures to Adjust Posture

Drs. Okumura and Kato propose the following 4 major countermeasures to improve dangerous sitting postures:

1. Get up and move your legs every 20-30 minutes of sitting.
2. If you cannot get up to move your legs, you should change your sitting posture, such as switching the leg you cross over the other.
3. Place a foot massage mat by your feet and gently tap your heels or shake your legs.
4. Combine with the correct breathing method to promote blood circulation, improve blood flow to the brain, strengthen core muscles, and prevent dementia and depression.