Obesity in South Korea: rates, causes and where to get help

How common is obesity in South Korea?

By international standards, obesity in South Korea is still uncommon: fewer than one adult in eleven has a BMI of 30 or more. With about 3.9 million adults affected, Korea is nevertheless among the 50 countries with the most people living with obesity.

The split between the sexes runs the other way from most of the world. In the WHO estimates, 10.4% of Korean men and 6.0% of Korean women live with obesity. Among children and teenagers aged 5 to 19, the gap is wider still: 19.4% of boys against 6.5% of girls.

That youth figure is unusual. In most countries, the adult rate is well above the rate in young people, but in Korea it is the other way round, with 13.1% of 5 to 19 year olds affected compared with 8.4% of adults.

Why Korean doctors use BMI 25

The Korean Society for the Study of Obesity (KSSO) defines obesity in adults as a BMI of 25 or more, not 30. Its guideline explains that Koreans, like other East Asian populations, face a higher risk of diabetes and heart disease at a lower BMI and tend to carry more abdominal fat at the same weight.

KSSO also treats a waist of 90 cm or more in men, or 85 cm or more in women, as abdominal obesity. A BMI from 23 to 24.9 is called pre-obesity. Our page on BMI and waist size explains why both numbers matter.

What Korean national data show

Korea has unusually rich data, because millions of adults take part in national health checks each year. The latest KSSO Obesity Fact Sheet, based on more than 17 million check-ups, finds that 38.4% of adults have obesity by the Korean definition: 49.8% of men and 27.5% of women. About 24% have abdominal obesity.

The most severe forms are concentrated in young adults. Class II obesity (BMI 30 to 34.9) peaks at 9.4% in people aged 35 to 39, and class III (BMI 35 or more) peaks among people aged 30 to 34.

The annual Korea National Health and Nutrition Examination Survey (KNHANES), run by the Korea Disease Control and Prevention Agency, tells a similar story. Its latest results put obesity among men at 48.8%, the highest level the survey has recorded, with 61.7% of men in their forties affected. Among women, the rate fell slightly to 26.2%.

These figures are far higher than the WHO rate because they use BMI 25 instead of 30. Both are correct; they simply answer different questions.

How has obesity in South Korea changed since 1990?

Obesity in South Korea has grown more than fivefold since 1990, from 1.5% to 8.4% of adults in the WHO estimates. The steepest climb has come recently: about fifteen years ago, the rate was still only 3.7%.

Men account for most of this change. In 1990, Korean women were more likely than men to have obesity (2.1% against 0.9%). Today, men have overtaken them, at 10.4% against 6.0%.

Young people have followed an even sharper path. Obesity among 5 to 19 year olds has risen from 2.6% to 13.1%, and among boys from 3.6% to 19.4%. A KSSO fact sheet using Korean growth charts found that obesity in children aged 6 to 18 roughly doubled within a decade, with the increase larger in boys.

Severe obesity is also becoming more common. Between the first and latest years of the national check-up series, class III obesity rose roughly threefold in men and more than doubled in women, and the change was largest in people in their twenties and thirties.

Why is obesity rising in South Korea?

Obesity in South Korea is rising mainly because everyday eating has moved away from the traditional Korean table, while daily movement has fallen. Our page on the causes of obesity explains how surroundings and biology work together.

From rice, soup and side dishes to flour, meat and sweets

A study of 16 years of national survey data found three main eating patterns among Korean adults: a traditional pattern, a "red meat and alcohol" pattern, and a "flour-based foods and sweets" pattern. Over time, the traditional pattern has given way to the more Westernised ones.

The flour-and-sweets pattern has been the most common for about a decade, especially among adults in their twenties and among women. Men who followed the red meat and alcohol pattern had the highest odds of obesity, abdominal obesity, raised blood sugar and high blood pressure.

Even kimchi, long a daily staple, is eaten less. A national analysis found that kimchi intake has fallen steadily among both men and women. The traditional table of rice, soup and several vegetable side dishes is still common, but it now shares space with bread, noodles, fried chicken and sweet drinks.

Working life and middle age

The heaviest burden falls on men in their thirties to fifties, the years when careers and family life leave the least free time.

In the national survey, almost half of men in their thirties and more than six in ten in their forties have obesity by the Korean definition, and the link between the red meat and alcohol eating pattern and excess weight was strongest in men.

Activity is falling in later life too. The national survey reports that regular aerobic exercise among people aged 65 and over has dropped from 46.1% to 37.1% over the past decade.

Young people and screen time

Children and teenagers face a food environment shaped by convenience stores, delivery apps and online food videos. A national survey of more than 100,000 adolescents found that two-thirds had watched "mukbang" or cooking broadcasts in the past year, and frequent viewing went along with more sugary drinks, late-night snacks and fast food.

That study looked at dental health rather than weight, but it shows how food messages now reach young Koreans through their phones. Our page on the food environment looks at how advertising and easy access shape choices.

How does obesity affect health in South Korea?

In South Korea, obesity is closely tied to diabetes, high blood pressure and raised cholesterol, and these conditions are becoming more common. The latest KSSO fact sheet found that chronic diseases were 1.5 to 3.6 times more common in adults with obesity than in those without, and obstructive sleep apnoea was 4.5 times more common.

The gap was especially large in young adults and in women. This matters because the youngest adults are also where severe obesity is growing fastest.

According to the Korean Diabetes Association's fact sheet, about 15.5% of Koreans over 30 have diabetes. The latest national survey also shows rising rates of high blood pressure, at 26.3% in men and 17.7% in women. You can read more about these links on our page on the health risks of obesity.

What is South Korea doing about obesity?

South Korea tackles obesity mainly through laws that protect children's food environment, national health screening, and insurance cover for treatment, rather than through taxes.

Green Food Zones and limits on junk-food advertising

Korea's Special Act on Safety Management of Children's Dietary Life created "Green Food Zones" around schools and limits the sale and advertising of high-calorie, low-nutrient foods to children. Later amendments have kept child protection at the centre of the law.

A review of almost two decades of obesity bills in the National Assembly found that measures framed around children were the ones most likely to pass. Calorie labelling in chain restaurants, BMI monitoring in schools and a Health-Friendly Workplace certification have also become law.

The same review shows where Korea has held back. A bill to tax sugary drinks, modelled on the taxes in Mexico and the United Kingdom, was proposed but not enacted, and Korea has opted for voluntary nutrition labels rather than mandatory front-of-pack warnings. Korea's approach so far relies on rules, education and screening.

Food education is part of the mix. An amendment to the Dietary Education Support Act added a programme that gives children and teenagers fruit and vegetables as regular snacks, which also supports Korean farmers.

Health checks for every adult

The National Health Insurance Service (NHIS) runs general health examinations that measure height, weight and waist alongside blood pressure, blood sugar and cholesterol. More than 17 million adults took part in a single recent year, which is why Korea has such detailed national obesity data.

For you, these check-ups are a regular chance to see your numbers and act on them early.

Insurance cover for surgery

Metabolic and bariatric surgery for people with severe obesity is now covered by national health insurance. A nationwide study of people treated after cover began found an average weight loss of about 22 kg after two years, and the number of people with diabetes in the group fell by 71%. Our page on bariatric surgery explains who this treatment is meant for.

Where can you get help for obesity in South Korea?

For most people in South Korea, the first step is the NHIS health check. If your result shows a BMI of 25 or more, a large waist, or raised blood sugar, blood pressure or cholesterol, book a follow-up with a local clinic doctor (family medicine or internal medicine) to talk about what the numbers mean.

Local public health centres (bogeonso) also run community programmes on healthy eating, activity and chronic disease, and the law requires them to employ certified health educators. If you live with severe obesity and other health problems, your doctor can refer you to a hospital team for a fuller assessment, which may include surgery.

The Korean Society for the Study of Obesity publishes the national treatment guideline and the yearly Obesity Fact Sheet. It is a good place to check that advice is based on evidence. Before an appointment, our doctor visit checklist helps you prepare questions.

How does South Korea compare with the world and East Asia?

South Korea's adult obesity rate of 8.4% is about half the world average. In East Asia, it sits above Japan (5.9%) and below China (9.3%) and North Korea (12.0%), while Mongolia is far higher at 25.1%.

Among young people the picture flips. Korea's rate for 5 to 19 year olds (13.1%) is above the world figure and slightly above China's (12.7%), and almost three times Japan's (4.7%). That makes childhood obesity one of the clearest warning signs for Korea's future health.

In 1990, the world rate was more than four times Korea's. Today it is under twice as high, because Korea's rate has climbed faster than the global one. See how other countries compare on our obesity by country page.

How Obesity Foundation can help you in South Korea

Obesity Foundation helps people in South Korea lose weight and get healthier with good food, suitable exercise and walking. All of our help is free and online. Talk to your doctor first before you change how you eat or move, especially if your health check flagged blood sugar or blood pressure.

Bring back the Korean table. Our free eating plan works well with bap, guk and banchan: a modest bowl of rice (mixed grains if you like), a clear soup, and two or three vegetable side dishes with fish, tofu or egg. Keep fried chicken, ramyeon and sweet coffee drinks for occasional treats rather than daily habits.

Walk the city. Korean cities are built for walking, with metro stations, riverside paths and hiking trails close to home. Our walking plan starts gently and builds up, and our low impact cardio routines suit a small apartment on rainy or very cold days.

Get support from people. Book a free video meeting (in English) to talk through your check-up results and set a realistic goal.

Join our club for steady encouragement, and use our free calculators to follow your BMI and waist. If you are a parent, our page on obesity in children has ideas for the whole family, and what obesity is explains the condition itself.