Inte exakt vad jag minns att jag har läst, men..... av senare dato.... saxat från wiki, det med, länkar till studier finns på sidan.
It is not clear where on the BMI scale the threshold for overweight and obese should be set. Because of this the standards have varied over the past few decades. Between 1980 and 2000 the U.S. Dietary Guidelines have defined overweight at a variety of levels ranging from a BMI of 24.9 to 27.1. In 1985 the National Institutes of Health (NIH) consensus conference recommended that overweight BMI be set at a BMI of 27.8 for men and 27.3 for women.
In 1998 a NIH report concluded that a BMI over 25 is overweight and a BMI over 30 is obese.[51] In the 1990s the World Health Organization (WHO) decided that a BMI of 25 to 30 should be considered overweight and a BMI over 30 is obese, the standards the NIH set. This became the definitive guide for determining if someone is overweight.
The current WHO and NIH ranges of normal weights are proved to be associated with decreased risks of some diseases such as diabetes type II; however using the same range of BMI for men and women is considered arbitrary, and makes the definition of underweight quite unsuitable for men.[52]
One study found that the vast majority of people labelled 'overweight' and 'obese' according to current definitions do not in fact face any meaningful increased risk for early death. In a quantitative analysis of a number of studies, involving more than 600,000 men and women, the lowest mortality rates were found for people with BMIs between 23 and 29; most of the 25?30 range considered 'overweight' was not associated with higher risk.[53]
