Nearly 25 percent of adult citizens in Seoul are obese amid a lack of exercise, with the proportion on the rise for the fourth consecutive year in 2012, a report showed Thursday.

According to the report by the Seoul Metropolitan Government, 23.4 percent out of 23,165 surveyed citizens aged 19 or older were obese in 2012, with 31.6 percent among male citizens and 16.5 percent among women.

The rate has been on a steady rise from 20.6 in 2008 when the municipal government began compiling related data and conducting a survey.

A person is diagnosed with obesity when his/her body mass index (BMI) measurement exceeds 25 kilograms per square meter and with extreme obesity when BMI measurement exceeds 30 kg/㎡. BMI measurements are obtained by dividing a person's body mass or weight by the square of the person's height.

By age group, 26.9 percent of citizens in their 60s and older, or the largest share, were obese, followed by those in their 40s and 50s at 26 percent and those in their 20s and 30s at 20 percent, according to the report.

The number of people who see themselves as overweight has also jumped by 10 percentage points over the past four years to 39.9 percent in 2012. Some 38.4 percent of males and 41.6 percent of females regarded themselves as obese, the report showed.

But fewer citizens are making efforts to lose weight, with the rate falling by 2.5 percentage points to 59.2 percent in 2012 from a year earlier.

Some 52.1 percent of the respondents said they walk 30 minutes per day on a regular basis for their health, and 16.8 percent said they do "vigorous exercises" such as climbing and jogging at least three times per week, down by 2 and 2.4 percentage points, respectively, according to the report.

"In a move to cut the obesity rate and to promote public health, the city government plans to launch a project to advise citizens to lose 3 kilograms for three months and maintain the weight for the following three months," a city official said. (Yonhap News)