William Atkins
Wednesday, 18 March 2009 19:19
Science -
Health
Page 2 of 4
The categories for BMI (body-mass index) are divided into four groups:
Underweight = <18.5
Normal weight = 18.5-24.9
Overweight = 25-29.9
Obesity = BMI of 30 or greater
The British researchers measured BMI versus mortality of participants in 57 different studies based in western Europe and North America. Sixty-one percent of the adults were male, and the mean age upon the start of the study was 46 years (plus or minus eleven years).
The median year that each participant started the study was 1979 (with a range of 1975 to 1985) and the mean BMI of the participants was 25 (with a standard deviation of four).
The researchers took into account such external factors as gender (sex), (tobacco) smoking habits, age, and other such factors. They did not count the first five years of deaths in order to better judge the cause of the death.
They found that the average age of death occurred at 67 years. The cause of 30,416 deaths was vascular (of the blood vessels) in nature; 2,070 was diabetic, renal, or hepatic (abnormally high blood sugar levels, or of the kidneys or liver); 22,592 was neoplastic (tissue growths); 3,770 was respiratory (of the lungs); and 7,704 was classified as “other.”
The researchers concluded that mortality for both males and females was lowest when BMI was between 22.5 and 25 kg/m
2, which is in the upper end of the normal weight category for BMI.
They found that a BMI of 30 to 39, classified as “moderate obesity,” reduces your life expectancy by three years, according to this study.
Page three talks about the amount of reduction in life span if you are severely obese.
