New Delhi: Modern work culture has made long office hours feel normal, whether people are working from home, commuting daily, or juggling multiple responsibilities at once. However, a new international study has now raised concerns about the hidden health impact of extended work schedules. Researchers have found that working long hours may be pushing the body to store what experts are calling “stress fat”, especially around the abdomen. The findings, presented at the European Congress on Obesity 2026, suggest that obesity is not only linked to unhealthy eating habits or lack of exercise, but also to stressful work patterns, lack of sleep, and “time poverty”. The study analysed data from 33 countries over more than two decades and discovered a strong connection between longer annual working hours and rising obesity rates.
This research is changing the way experts look at weight gain and workplace health. Instead of blaming individuals alone for obesity, scientists are now highlighting the role of chronic stress, cortisol levels, sedentary lifestyles, and demanding work schedules. The study also adds fuel to the growing debate around flexible working hours and four-day workweeks. If you have been struggling with unexplained belly fat, low energy, or weight gain despite eating carefully, your job stress and working hours could be playing a much bigger role than you realise.
What is ‘Stress fat’ and why is it dangerous
Stress fat refers to fat stored in the body due to chronic stress and elevated cortisol levels. Cortisol is commonly known as the “stress hormone”. When the body remains under pressure for long periods, cortisol levels stay high, encouraging fat storage, particularly around the stomach area.
Experts say this type of fat is more concerning because abdominal fat is closely linked to conditions such as heart disease, type 2 diabetes, high blood pressure, and metabolic disorders. The body reacts to prolonged stress by trying to conserve energy, which often leads to increased appetite, cravings for sugary foods, and slower fat burning.
New study finds clear link between long working hours and obesity
The latest research presented at the European Congress on Obesity examined data collected from 33 OECD countries between 1990 and 2022. Researchers found that countries with longer average working hours also reported higher obesity rates.
According to the study, even a 1% reduction in annual working hours was associated with a 0.16% decrease in obesity prevalence. Countries such as Colombia, Mexico, and Costa Rica, where people generally work longer hours, recorded higher obesity levels. Meanwhile, countries with shorter work schedules, including Germany, Norway, and the Netherlands, showed lower obesity rates.
Researchers believe that excessive working hours create “time poverty”, leaving people with less time for exercise, meal preparation, sleep, and self-care.
How long working hours increase belly fat
There are several ways long working hours can affect the body and contribute to stress fat accumulation.
1. Chronic stress raises cortisol levels: When employees are constantly under deadlines, pressure, and workload stress, the body remains in a prolonged stress response. This increases cortisol production, which promotes fat storage around the abdomen.
2. Sitting for long periods slows fat burning: Desk jobs and screen-heavy work routines reduce physical movement throughout the day. Lower activity levels mean the body burns fewer calories, increasing the chances of weight gain.
3. Lack of sleep disrupts hormones: People working long hours often sacrifice sleep. Poor sleep affects hormones linked to hunger and metabolism, making unhealthy food cravings more common.
4. Stress eating becomes more common: Busy schedules leave little time for healthy meals, pushing many workers towards processed foods, takeaway meals, sugary snacks, and late-night eating habits.
Men may be more affected than women
Interestingly, the study found that the impact of long working hours on obesity appeared stronger in men.
Researchers observed that a 1 percent reduction in annual working hours could reduce obesity rates by around 0.23% in men, compared with 0.11 percent in women during certain periods studied. Scientists believe this could be linked to higher exposure to workplace stress, sedentary jobs, and social pressure related to financial responsibilities.
However, experts also noted that women often face the combined burden of professional work and unpaid household responsibilities, which can also contribute to stress and poor health outcomes.
Simple ways to reduce stress fat while working long hours
Although changing work culture may take time, there are still practical ways people can protect their health during busy work schedules.
- Take short movement breaks every 30 to 45 minutes
- Go for walks after meals
- Prioritise 7 to 8 hours of sleep
- Include protein and fibre-rich foods in meals
- Practise stress management through yoga, meditation, or breathing exercises
- Avoid relying heavily on processed snacks and sugary drinks
- Try stretching or standing while taking phone calls
The new obesity study highlights an important reality of modern life – long working hours may be affecting health far more than people realise. Chronic stress, lack of movement, poor sleep, and unhealthy eating habits caused by demanding work schedules can all contribute to the build-up of dangerous “stress fat”.