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点击查看： Definitions of Obesity A: How does one define when a person is considered to be obese and not just somewhat overweight? Height-weight tables give an approximate guideline as to whether one is simply overweight or has passed into the obese stage. B: The World Health Organization recommends using a formula that takes into account a persons height and weight. The Body Mass Index is calculated by dividing the persons weight in kilograms by the square of their height in meters, and is thus given in units of kg/m2. A BMI of 18.5-24.9 is considered to be the healthiest. A BMI of between 25 and 29.9 is considered to be overweight, while a BMI of over 30 is considered to be obese. C: However, it is recognized that this definition is limited as it does not take into account such variables as age, gender and ethnic origin, the latter being important as different ethnic groups have very different fat distributions. Another shortcoming is that it is not applicable to certain very muscular people such as athletes and bodybuilders, who can also have artificially high BMIs. Agencies such as the National Cholesterol Education Program in the USA and the International Diabetes Foundation are starting to define obesity in adults simply in terms of waist circumference. Health Effects of Obesity D: Over 2000 years ago, the Greek physician Hippocrates wrote that persons who are naturally very fat are apt to die earlier than those who are slender. This observation remains very true today. Obesity has a major impact on a persons physical, social and emotional well-being. It increases the risk of developing diabetes mellitus type 2 and also makes Type 2 diabetes more difficult to control. Thus weight loss improves the levels of blood glucose and blood fats, and reduces blood pressure. The association between obesity and coronary heart disease is also well-known. | 
