People need to ditch the obsession¹ with body mass index and rethink the way they judge obesity², a new report states.

一项最新研究指出，人们应该摆脱对体质指数的迷信，重新审视自己对肥胖的看法。

Researchers from the University of Alberta say the metric, which measures a person's body size from their weight and height, has become a benchmark in modern medicine.

据来自阿尔伯塔大学的研究人员表示，通过测量人的身高和体重来衡量一个人的体型度，已经成为现代医学的一个基准。

But body mass index (BMI) is not only a bad indicator³ of how healthy you are, it can lead to doctors prescribing the wrong treatment for patients, the scientists say.

但是科学家们表示，体质指数不仅不能说明你健康与否，还可能会导致医生为病人制定错误的治疗方案。

BMI first gained popularity in the 1970s as a way of judging body fat. A healthy BMI is typically measured between 18.5 and 24.9.

作为一种衡量体脂的方法，体质指数第一次被人们接受是在上世纪70年代。健康的体质指数一般在18.5到24.9之间。

Anything under 18.5 is considered underweight. BMIs between 25 and 29.9 fall into overweight territory, and above 30 is considered obese⁴.

体质指数低于18.5则会被认为体重过轻，25到29.9之间则会被认为过重，30以上就是肥胖了。

It is useful for tracking population trends in body weight, but has well-known limitations when applied⁵ to individuals, Dr Arya Sharma, an obesity researcher at the University of Alberta in Canada, told Live Science.

加拿大阿尔伯塔大学肥胖研究者艾丽娅·夏尔马博士向Live Science透露，体质指数用来追踪人口体重变化是有用的，但是当适用于个人的时候就有很多众所周知的限制性了。

For example, many professional athletes qualify as overweight or obese based on solely⁶ their BMI. But they have much more muscle mass, which weighs proportionally more than fat.

比如说，如果只看体质指数的话，许多职业运动员都是过重或者肥胖。但是他们的肌肉要多得多，占比远超脂肪含量。

And while someone with a BMI of above 30 is considered obese by the metric, they may actually be perfectly⁷ healthy, metabolically⁸ speaking, according to Dr Sharma.

根据夏尔马博士的说法，尽管某些人体质指数高于30并被认为是肥胖，但是事实上从新陈代谢的角度来讲，他们可能非常健康。

Their blood pressure is normal, their livers are functioning well and their cholesterol⁹ levels are within normal limits.

他们的血压正常、肝功能良好、胆固醇水平也在正常范围之内。

On the other hand, some people with BMIs below 30 have health problems if they were to lose weight.

而另一方面，如果某些体质指数低于30的人减肥的话，他们可能会出现一些健康问题。