Epidemiology of obesity

Asia

China

In the twenty first century, China faces challenges of obesity and chronic disease. This is believed to be primarily due to the rapid declines in physical activity and changing dietary habits which have occurred between the 1980s and the 2000s. The decline in physical activity is attributed to increasing technology in the workplace and changing leisure activities.

In 1989 65% of Chinese had jobs that required heavy labor. This decreased to 51% in the year 2000. Combined with this has been a change to a diet higher in meat and oil, and an increase in overall available calories. Available calories per person increased from 2,330 kilocalories (9,700 kJ) per day in 1980 to 2,940 kilocalories (12,300 kJ) per day in 2002. Rates of overweight and obese adults increased 12.9% in 1991 to 27.3% in 2004.

Overall rates of obesity are below 5% in China as a whole but are greater than 20% in some cities.

India

Obesity has reached epidemic proportions in India in the 21st century, with morbid obesity affecting 5% of the country's population. Obesity is a major risk factor for cardiovascular disease and NGOs such as the Indian Heart Association have been raising awareness about this issue. Urbanization and modernization has been associated with obesity. In Northern India obesity was most prevalent in urban populations (male = 5.5%, female = 12.6%), followed by the urban slums (male = 1.9%, female = 7.2%). Obesity rates were the lowest in rural populations (male = 1.6%, female = 3.8%).

Socioeconomic class also had an effect on the rate of obesity. Women of high socioeconomic class had rates of 10.4% as opposed to 0.9% in women of low socioeconomic class. With people moving into urban centers and wealth increasing, concerns about an obesity epidemic in India are growing.

Indonesia

Iran

In Iran the prevalence of obesity was 26.3% in 2008. Prevalence of obesity was more among women (39.5%) than men (14.5%).

Japan

Using the WHO criteria Japan has the lowest rate of obesity among the OECD member countries at 3.2%. However, as Asian populations are particularly susceptible to the health risks of excess adipose tissue, the Japanese have redefined obesity as any BMI greater than 25. Using this cut off value the prevalence of obesity in Japan would be 20%, a threefold increase from 1962 to 2002. A 2008 report stated that 28.6% of men and 20.6% of women in Japan were considered to be obese.

Pakistan

Changing lifestyles, owing to urbanisation, as well as diet issues are the main reasons for obesity in Pakistan. According to a recent study, approximately one out of four Pakistani adults (or 22.2% of individuals) are classified as obese.

Qatar

According to WHO data from 2022, Qatar has the highest rate of obesity (43.1%) of any country in Asia.

Saudi Arabia

Taiwan

In 2002, 15% of children from 6 to 12 years of age were overweight; by gender, 15.5% of males and 14.4% of females were overweight. In the same age range, 12% of children were obese; by gender, 14.7% of males and 9.1% of females were categorized as obese. In 2005, 14.9% children from 6 to 12 years of age were overweight; by gender, 15.85% of males and 14.02% of females were overweight. 10.3% were categorized as obese; by gender, 10.92% of males and 9.73% of females were categorized as obese.

Based on these numbers, the trends were inconclusive, although with more than 10% of the age group being obese, obesity does appear to be a problem.

Thailand

Vietnam

According to WHO data from 2022, Vietnam has the lowest obesity rate in the world at 2%.

Europe

Between the 1970s and the 2000s, rates of obesity in most European countries have increased. During the 1990s and 2000s, the 27 countries making up the EU reported rates of obesity from 10 to 27% in men and from 10 to 38% in women.

The most recent combined Eurostat statistics, for 2009, show that, among the 19 EU Member States for which data are available, the proportion of obese people in the adult population varied in 2008/9 between 8.0% (Romania) and 23.9% (UK) for women and between 7.6% (Romania) and 24.7% (Malta) for men. Overall the UK had the highest proportions, and Romania the lowest. Men, the elderly and people with lower educations also have significantly higher obesity rates.

Austria

France

Germany

Greece

Ireland

Italy

Malta

Sweden

Switzerland

United Kingdom

In the UK the rate of obesity has increased about fourfold over the last 30 years, reaching levels of 22–24% in 2008/9.

North America

Epidemiological data show that, among high-income countries, obesity prevalence is highest in the United States and Mexico.

Canada

The number of Canadians who are obese has risen dramatically in recent years. In 2004, direct measurements of height and weight found 23.1% of Canadians older than 18 had a BMI greater than 30. When broken down into degrees of obesity, 15.2% were class I (BMI 30–34.9), 5.1% were class II (BMI 35–39.9), and 2.7%, class III (BMI ≥ 40). This is in contrast to self-reported data the previous year of 15.2% and in 1978/1979 of 13.8%. The greatest increases occurred among the more severe degrees of obesity; class III obesity increased from 0.9% to 2.7% from 1978/1979 to 2004. Obesity in Canada varies by ethnicity; people of Aboriginal origin have a significantly higher rate of obesity (37.6%) than the national average.

In children obesity has substantially increased between 1989 and 2004 with rates in boys increasing from 2% to 10% and rates among girls increasing from 2% to 9%.

Mexico

Mexico has one of the highest rates of obesity among OECD countries, second only to the United States. To combat the epidemic, in 2014 Mexico implemented new taxes levied on food with excessive energy content and on sugar-sweetened beverages.

United States

Obesity rates in the United States have nearly tripled since the 1960s. In 1962, about 13% of adult Americans were obese, and by 2002, obesity rates reached 33% of the adult population. According to the National Health and Nutrition Examination Study collected between the 1970s and 2004, the prevalence of overweight and obesity increased steadily among all groups of Americans. The numbers continue to rise; as of 2007, 33% of men and 36% of women were obese, and by 2015–2016, 39.6% of the total adult population (37.9% of men and 41.1% of women) had obesity. As of 2017–2018, 42.4% of U.S. adults aged 20 and over were obese (43% for men and 41.9% for women).

Obesity rates vary between diverse social groups, with some racial groups and low-income individuals more likely to be obese while other minorities show lower rates. As of 2014 the rates were as low as 12% for non-Hispanic Asian women and as high as 57% among African American women.

The incidence of obesity also varies with geography. The American South has been referred to as the "Stroke belt", "Obesity belt", or "Diabetes belt", to reflect the fact that residents of the region have high rates of these three conditions, compared to people of the same race/ethnicity elsewhere in the country.

Based on a study in 2008, estimates of obesity that rely on self-reported data arrive at a rate of 22% among non-Hispanic white females, whereas studies that involve direct measurement show that the rate was closer to 34% at that time.

The prevalence of class III (morbid) obesity (BMI ≥ 40) has increased the most dramatically, from 1.3% in the late 1970s, to 2.9% in 1988–94, to 4.7% in 2000, to 5.7% in 2008, and to 7.7% in 2014. Among African American women, its prevalence is estimated to be as high as 17%.

The rate of increase in the incidence of obesity began to slow in the 2000s, but as of 2014, obesity, severe obesity, and obesity in children continued to rise.

Obesity is one of the leading health issues in the United States, with some estimates suggesting that obesity results in about 300,000 excess deaths per year. However, in 2005 using different methodology, research at the Centers for Disease Control and Prevention produced a nationwide estimate of 129,000 excess deaths per year relative to individuals with a BMI of 21 to 25.

South America and the Caribbean

Surveys in different Caribbean countries found that 7-20% of males and 22-48% of females over the age of 15 are obese. Trinidad and Tobago has the highest obesity in the Caribbean, with over 30% of its adult population overweight, ranking the country sixth in the world. The Bahamas have a major obesity epidemic: 48.6% of people between 15 and 64 years old are obese. A female adolescent from the Bahamas is more likely to be overweight than her male counterpart. In Jamaica, 7.2% of men over the age of 20 are obese, while 31.5% of women are obese.

Argentina

Bahamas

According to WHO data from 2022, The Bahamas has the highest rate of obesity (47.3%) of any country in the Americas.

Chile

According to WHO data from 2022, Chile has the highest obesity rate (38.5%) of any country in South America.

Oceania and the Pacific

Australia

Australia has a large obese population. According to self-reported and measured results of the 2007–2008 National Health Survey, 61% of Australians were overweight (above a 25 BMI), with 24% falling into the "obese" category (above a 30 BMI). Men were more likely to be overweight (67.7%) and obese (25.5%) than women (30.9% and 23.4% respectively).

New Zealand

Obesity in New Zealand has become an important national health concern in recent years, with high numbers of people afflicted in every age and ethnic group. In 2011/12, 28.4% of New Zealand adults were obese, a number only surpassed in the English-speaking world by the United States.

South Pacific

Many of the island nations of the South Pacific have very high rates of obesity. Nauru has the highest rates of obesity in the world (94.5%) followed by Samoa, the Federated States of Micronesia, and the American Samoa. Being big has traditionally been associated with health, beauty, and status and many of these beliefs remain prevalent today.

Statistics

Estimated prevalence of obesity with BMI >= 30 among adults by country according to World Health Organization for year 2022: