The Hidden Health Risk of Sitting
Arriving at the office in the morning and sitting in front of a computer, returning to the desk after lunch and staring at a monitor until leaving time. This ordinary routine repeated daily by most office workers has emerged as one of the biggest risk factors threatening brain health, according to a new analysis.
The number of dementia patients aged 65 and older in Korea is estimated at approximately 970,000 in 2025, according to the '2023 Dementia Epidemiological Survey and Status Report' released by the Ministry of Health and Welfare and the Central Dementia Center. The figure is projected to enter the one million range next year in 2026 and surpass two million by 2044. The same survey predicted that the number of people diagnosed with mild cognitive impairment will exceed 4 million by 2033, up from 2.98 million this year. This means 28.12% of the population aged 65 and older falls into the mild cognitive impairment category.
The Strong Link Between Sitting and Dementia
Meanwhile, a recent study by researchers at York University in Canada, which analyzed data from millions of adults aged 35 and older, found that people who sit for more than eight hours a day have a 27% higher risk of developing dementia than those who do not. Akinkunle Oyeyemi, who led the research, stressed that 'even people who are usually active cannot be free from dementia risk if they sit for long periods.' The study was published in the latest issue of the international journal PLOS One.
Exercise Cannot Fully Offset Sedentary Time
The fact that the effects of exercise do not fully offset sedentary time has also been confirmed in other research. According to a study published in JAMA Cardiology in 2022, even people who meet the World Health Organization's recommended exercise levels showed premature death risks similar to the exercise-deficient group if they sat for more than six hours a day. Sedentary time was confirmed to be an independent risk factor separate from exercise volume.
How Does Sitting Harm the Brain?
The cause lies in the body's physiological changes. When sitting, metabolism slows down sharply. As energy consumption decreases, triglycerides accumulate in the blood, and the secretion of lipoprotein lipase (LPL), an enzyme that breaks down fat, also declines. When this inactive state accumulates over months or years, insulin resistance increases and blood sugar control becomes impaired. This eventually raises the risk of not only type 2 diabetes but also dementia, cardiovascular disease, and premature death. This is the pathway through which simply 'sitting a lot' affects even the brain.
Solution: Break Up Sitting Time
The solution is not to increase exercise time but to 'break up continuous sitting time.' Simply standing up and walking lightly for about two minutes every 30 minutes provides meaningful benefits for maintaining metabolism and regulating blood sugar. Taking phone calls while standing and holding short meetings while walking, known as 'walking meetings,' are also effective. Standing desks alone have little effect—they only change posture without leading to increased physical activity. Ultimately, the most powerful medicine for protecting the brain decades later is not the gym after work, but the small habit of standing up every 30 minutes during work hours.