Obesity Facts & Figures

Obesity Facts & Figures:  Useful Resources from the WHO Regional Office for Europe:

Obesity Facts & Figures: World Health Organisation Fact sheet N°311

Key facts

  • Worldwide obesity has nearly doubled since 1980.
  • In 2008, more than 1.4 billion adults, 20 and older, were overweight. Of these over 200 million men and nearly 300 million women were obese.
  • 35% of adults aged 20 and over were overweight in 2008, and 11% were obese.
  • 65% of the world’s population live in countries where overweight and obesity kills more people than underweight.
  • More than 40 million children under the age of five were overweight in 2011.
  • Obesity is preventable.

What are overweight and obesity?

Overweight and obesity:

  • are defined as abnormal or excessive fat accumulation that may impair health;
  • have important consequences for morbidity, disability and quality of life;
  • entail higher risk of developing type 2 diabetes, cardiovascular diseases, several common forms of cancer, osteoarthritis and other health problems; and
  • are serious public health challenges in the WHO European Region.

Definitions

Overweight and obesity are often measured using the BMI (Body Mass Index) scale.  BMI:

  • is a simple index commonly used to classify overweight and obesity in schoolchildren and adults;
  • is calculated as a person’s weight (in kg) divided by his or her height (in m2); and
  • does not distinguish weight associated with muscle from weight associated with fat and therefore provides only a crude measure of fatness.

BMI provides the most useful population-level measure of overweight and obesity as it is the same for both sexes and for all ages of adults. However, it should be considered a rough guide because it may not correspond to the same degree of fatness in different individuals.

The WHO definitions of overweight and obesity are:

  • a BMI greater than or equal to 25 is overweight
  • a BMI greater than or equal to 30 is obesity

WHO BMI Cut Off Points:

Category BMI range – kg/m2
Very severely underweight less than 15
Severely underweight from 15.0 to 16.0
Underweight from 16.0 to 18.5
Normal (healthy weight) from 18.5 to 25
Overweight from 25 to 30
Obese Class I (Moderately obese) from 30 to 35
Obese Class II (Severely obese) from 35 to 40
Obese Class III (Very severely obese) over 40

Facts about overweight and obesity

Overweight and obesity are the fifth leading risk for global deaths. At least 2.8 million adults die each year as a result of being overweight or obese. In addition, 44% of the diabetes burden, 23% of the ischaemic heart disease burden and between 7% and 41% of certain cancer burdens are attributable to overweight and obesity.

Some WHO global estimates from 2008 follow.

  • More than 1.4 billion adults, 20 and older, were overweight.
  • Of these overweight adults, over 200 million men and nearly 300 million women were obese.
  • Overall, more than 10% of the world’s adult population was obese.

In 2011, more than 40 million children under the age of five were overweight. Once considered a high-income country problem, overweight and obesity are now on the rise in low- and middle-income countries, particularly in urban settings. More than 30 million overweight children are living in developing countries and 10 million in developed countries.

Overweight and obesity are linked to more deaths worldwide than underweight. For example, 65% of the world’s population live in countries where overweight and obesity kill more people than underweight (this includes all high-income and most middle-income countries).

What causes obesity and overweight?

The fundamental cause of obesity and overweight is an energy imbalance between calories consumed and calories expended. Globally, there has been:

  • an increased intake of energy-dense foods that are high in fat; and
  • an increase in physical inactivity due to the increasingly sedentary nature of many forms of work, changing modes of transportation, and increasing urbanization.

Changes in dietary and physical activity patterns are often the result of environmental and societal changes associated with development and lack of supportive policies in sectors such as health, agriculture, transport, urban planning, environment, food processing, distribution, marketing and education.

What are common health consequences of overweight and obesity?

Raised BMI is a major risk factor for noncommunicable diseases such as:

  • cardiovascular diseases (mainly heart disease and stroke), which were the leading cause of death in 2008;
  • diabetes;
  • musculoskeletal disorders (especially osteoarthritis – a highly disabling degenerative disease of the joints);

The risk for these noncommunicable diseases increases, with the increase in BMI.

Childhood obesity is associated with a higher chance of obesity, premature death and disability in adulthood. But in addition to increased future risks, obese children experience breathing difficulties, increased risk of fractures, hypertension, early markers of cardiovascular disease, insulin resistance and psychological effects.

Facing a double burden of disease

Many low- and middle-income countries are now facing a “double burden” of disease.

  • While they continue to deal with the problems of infectious disease and under-nutrition, they are experiencing a rapid upsurge in noncommunicable disease risk factors such as obesity and overweight, particularly in urban settings.
  • It is not uncommon to find under-nutrition and obesity existing side-by-side within the same country, the same community and the same household.

Children in low- and middle-income countries are more vulnerable to inadequate pre-natal, infant and young child nutrition At the same time, they are exposed to high-fat, high-sugar, high-salt, energy-dense, micronutrient-poor foods, which tend to be lower in cost but also lower in nutrient quality. These dietary patterns in conjunction with lower levels of physical activity, result in sharp increases in childhood obesity while undernutrition issues remain unsolved.

Childhood Obesity

Prevalence of childhood obesity is very high in Europe.  According to the recent COSI study by WHO, 19.3-49.0% of boys and 18.4-42.5% of girls were overweight (including obesity and based on the 2007 WHO growth reference).The prevalence of obesity ranged from 6.0 to 26.6% among boys and from 4.6 to 17.3% among girls. Multi-country comparisons suggest the presence of a north-south gradient with the highest level of overweight found in southern European countries (Pediatric Obesity, 2013).

As such, there is an immense need for the development of effective treatments. Worldwide, medical personnel and researchers are making great efforts to develop treatments that will fulfil this need. The two most recent Cochrane reviews on prevention and treatment (2009, 2011) concluded that as of yet there is not a defined long-term effective and sustainable intervention thus multiple research groups are investigating their own treatment approaches. As of June 2013 the American Medical Association officially recognised obesity as a disease and this decision will lead to more focused approach around the world with regard to an individual access to treatment and in relation to the type of treatment that they receive.

Paediatric obesity research is conducted in a vulnerable group of patients and families. Many families live in low-income neighbourhoods. The negative association with parental education is repeatedly seen even in highly developed European countries. Many obese children suffer from significant emotional problems ranging from overt depression to disturbed eating behaviour. Added to this, obesity carries a social stigma that adversely affects children as well as their families.

When considering future development of care, it is worthwhile to remember that childhood obesity is a long-term condition with associated co-morbidities, many of which are not always readily identifiable. Clinical studies suggest that almost 50% of obese children exhibit pre- or grade 1 or 2 high blood pressure hypertension, another 29% exhibit high cholesterol levels, 44% exhibit more than 5% fat in their livers and 74% exhibit more than 5% fat in their muscles. Additionally, may children suffer from endocrinological, orthopaedic and psychological. Furthermore, future health risks loom and a significant risk of cardiovascular disease, metabolic disease and cancer seems to be non-ignorable in adulthood.

How can overweight and obesity be reduced?

Overweight and obesity, as well as their related noncommunicable diseases, are largely preventable. Supportive environments and communities are fundamental in shaping people’s choices, making the healthier choice of foods and regular physical activity the easiest choice (accessible, available and affordable), and therefore preventing obesity.

At the individual level, people can:

  • limit energy intake from total fats and sugars;
  • increase consumption of fruit and vegetables, as well as legumes, whole grains and nuts;
  • engage in regular physical activity (60 minutes a day for children and 150 minutes per week for adults).

Individual responsibility can only have its full effect where people have access to a healthy lifestyle. Therefore, at the societal level it is important to:

  • support individuals in following the recommendations above, through sustained political commitment and the collaboration of many public and private stakeholders;
  • make regular physical activity and healthier dietary choices available, affordable and easily accessible to all – especially the poorest individuals.

The food industry can play a significant role in promoting healthy diets by:

  • reducing the fat, sugar and salt content of processed foods;
  • ensuring that healthy and nutritious choices are available and affordable to all consumers;
  • practicing responsible marketing especially those aimed at children and teenagers;
  • ensuring the availability of healthy food choices and supporting regular physical activity practice in the workplace.

Source: World Health Organisation Fact sheet N°311