Extra Weight or ObesityOne of the most common problems related to lifestyle today is being overweight. Severe overweight or obesity is a key risk factor in the development of many chronic diseases such as heart and respiratory diseases, non-insulin-dependent diabetes mellitus or Type 2 diabetes, hypertension and some cancers, as well as early death. New scientific studies and data from life insurance companies have shown that the health risks of excessive body fat are associated with relatively small increases in body weight, not just with marked obesity.
BMI: Weight (kg) / Height (m)²
Obesity and overweight are serious problems that pose a huge and growing financial burden on national resources. However, the conditions are largely preventable through sensible lifestyle changes.
What is obesity and overweight?Obesity is often defined simply as a condition of abnormal or excessive fat accumulation in the fat tissues (adipose tissue) of the body leading to health hazards. The underlying cause is a positive energy balance leading to weight gain i.e. when the calories consumed exceed the calories expended.
In order to help people determine what their healthy weight is, a simple measure of the relationship between weight and height called the Body Mass Index (BMI) is used. BMI is a useful tool that is commonly used by doctors and other health professionals to determine the prevalence of underweight, overweight and obesity in adults. It is defined as the weight in kilograms divided by the square of the height in metres (kg/m2). For example, an adult who weighs 70 kg and whose height is 1.75 m will have a BMI of 22.9 kg/m2.
Overweight and obesity are defined as BMI values equals or exceeding 25 and 30, respectively. Typically, a BMI of 18.5 to 24.9 is considered ‘healthy’, but an individual with a BMI of 25–29.9 is considered "at increased risk" of developing associated diseases and one with a BMI of 30 or more is considered at "moderate to high risk"
|BODY MASS INDEX|
|18,5 - 24,9 Healthy weight|
|25 - 29,9 Overweight|
Fat distribution: apples and pearsBMI still does not give us information about the total fat or how the fat is distributed in our body, which is important as abdominal excess of fat can have consequences in terms of health problems.
A way to measure fat distribution is the circumference of the waist. Waist circumference is unrelated to height and provides a simple and practical method of identifying overweight people who are at increased risk of obesity-related conditions. If waist circumference is greater than 94-102 cm for men and 80-88 cm for women, it means they have excess abdominal fat, which puts them at greater risk of health problems, even if their BMI is about right
The waist circumference measurement divides people into two categories: individuals with an android fat distribution (often called “apple” shape), meaning that most of their body fat is intra-abdominal and distributed around their stomach and chest and puts them at a greater risk of developing obesity-related diseases. Individuals with a gynoid fat distribution (often called “pear” shape), meaning that most of their body fat is distributed around their hips, thighs and bottom are at greater risk of mechanical problems (e.g. joints, thighs). Obese men are more likely to be “apples “while women are more likely to be “pears”.
References: • World Heath Organisation, Physical status: the use and interpretation of anthropometry. Report of a WHO Expert Committee. WHO Technical Report Series, No 854, 1995.
• Han, T.S., et al., The influences of height and age on waist circumference as an index of adiposity in adults. International Journal of Obesity, 1997. 21: p. 83-89.
• Lean, M.E.J., T.S. Han and C.E. Morrison, Waist circumference as a measure for indicating the need for weight management. British Medical Journal, 1995. 311: p. 158-161.
• Lean, M.E.J., T.S. Han and J.C. Seidell, Impairment of health and quality of life in people with large waist circumference. Lancet, 1998. 351: p. 853-856.
• Lemieux, S., et al., Sex differences in the relation of visceral adipose tissue accumulation to total body fatness. American Journal of Clinical Nutrition, 1993. 58: p. 463-467.