Obesity & Overweight

Obesity & Overweight

1. Obesity and overweight are defined as an abnormal/excessive amount of fat accumulation that may impair health

   • Overweight and obesity were considered to be problems of high income countries, but are dramatically on the rise in low and middle income countries, particularly in urban areas
   • Many low/middle income countries are now facing a 'double burden' of disease. Whilst continuing to deal with infectious disease and undernutrition, they are experiencing rapid upsurges of chronic diseases due to overweight and obesity at the same time - particularly in urban areas
     • It is not uncommon to find undernutrition and obesity existing side by side in the same country/community/household. This double burden is caused by inadequate prenatal, infant and childhood nutrition followed by lack of physical activity and exposure to high fat and energy dense foods

2. Body Mass Index (BMI)

   • BMI is a simple index of weight for height that is commonly used in classifying overweight and obesity in adult individuals or population
   • It is defined as weight (in kilograms) divided by the square of height in meters
   • The WHO defines 'overweight as a BMI equal or more than 25, and obesity as equal to or more than 30

3. Measuring overweight and obese children aged 5 - 14 is difficult because a standard definition of childhood obesity is not applied worldwide

   • The WHO is currently developing an international growth reference for school aged student and adolescents

4. WHO's figures conclude that in 2005...

   • at least 400 million adults were obese
   • at least 20 million children under the age of 5 years were overweight
   • Childhood obesity is a big problem in the USA where over 35% of children are overweight

5. The fundamental causes of obesity and overweight is an energy imbalance between calories consumed and calories expended. Global increases of this can be attributed to...

   • a global shift in diet towards the increase intake of energy-dense foods that are high in fats & sugars but low in vitamins & minerals
   • a trend towards decreased physical activity due to the increasingly sedentary nature of many forms of work, changing modes of transportation and increasing urbanisation

6. Health consequences

   • Raised BMI is a major risk factor for many chronic diseases such as..
     • Cardiovascular disease, diabetes, musculoskeletal disorders and some cancers

7. Childhood obesity is also associated with a higher chance of premature death and disability in adulthood.

   • Life expectancy is reduced by an average of 14 years for obese smokers compared with non-smokers of normal weight
   • More than 60% of adults in the USA are overweight or obese. There are 70 million overweight people in China

8. Reducing overweight and obesity is largely preventable, at an individual level people can..

   • achieve a healthy weight by reducing calorie intake and exercising more
   • limit energy intake from fats and shift fat consumption from saturated to unsaturated
   • increase compensation of fruit and vegetables, whole grains and nuts
   • limit the intake of sugars
   • increase physical activity - at least 30 minutes of regular, moderate-intensity activity on most days. More activity may be required for weight loss
   • the implementation of these rrecommendations requires sustained political commitment
     • Governments, NGOs and the private sector have vital roles in creating healthy enviroments and making healthier diet options affordable and accessible
       • The following initiatives by the food industry could accelerate health gains worldwide...
         • reducing the fat, sugar and salt content of processed foods
         • reducing portion sizes
         • introducing new innovative, healthy and nutritious choices
         • reviewing current marketing practices