There are many environmental, social, physiological & behavioural reasons why people can be overweight & obese. The most basic reason however, is that the energy balance between what an individual eats (the energy in) & how that energy is used (the energy out) is uneven leading to excess energy being stored in the body as fat.
Because of this energy balance principle, people who eat a high-fat, high-energy diet & do not exercise will almost certainly gain weight. There are also a number of other reasons why some people gain excess weight more quickly than others.
Overweight & obesity are more common in lower socio-economic groups, in rural & remote populations, in certain ethnic groups, & in Aboriginal & Torres Strait Islander people.
Consequences of Obesity
There are many health risks involved with being overweight or obese.
The physical health problems can range from contribute to a range of life-threatening illness, including:
Type 2 diabetes
Coronary artery disease
Some types of cancers
There is a number of health as well as social & psychological consequences associated with being overweight or obese.
Psychosocial consequences include:
Body shape dissatisfaction
Eating disorders, e.g. binge-eating disorder
It is important then to prevent excess weight gain, not just for general good health & wellbeing but in order to avoid the more serious problems that obesity can bring about. Fortunately losing excess weight can often slow or reverse many of these disorders.
References www.aso.org.uk - The Association for the Study of Obesity. NSW Centre for Public Health Nutrition. State of Food and Nutrition in NSW Series: Report on the Weight Status of NSW: 2003. Sydney: NSW Department of Health, 2003. National Health and Medical Research Council. Acting on Australia’s Weight: A Strategic Plan for the Prevention of Overweight and Obesity. Canberra: AGPS, 1997.