紐時賞析／新健康指標「BRI」登場！可評估腹部脂肪 還有望用於預測死亡率

情境示意圖。圖／Ingimage

Time to Say Goodbye to the BMI?

該是向BMI道別的時候？

Move over, body mass index. Make room for roundness — to be precise, the body roundness index.

挪開吧，身體質量指數。讓位給圓度，更精確地說，身體圓度指數。

The body mass index, or BMI, is a ratio of height to weight that has long been used as a medical screening tool. It is one of the most widely used health metrics but also one of the most reviled, because it is used to label people overweight, obese or extremely obese.

身體質量指數，或簡稱BMI，是一項身高與體重的比率，長期以來被用作疾病篩檢工具。BMI是使用最廣泛的健康指標之一，但因把人貼上超重、肥胖或極度肥胖的標籤，也是最爲人詬病的指標之一。

The classifications have been questioned by athletes including American Olympic rugby player Ilona Maher, whose BMI of 30 technically puts her on the cusp of obesity. “But alas,” she said on Instagram, addressing online trolls who tried to shame her about her weight, “I’m going to the Olympics and you’re not.”

這樣的分類也遭到美國奧運橄欖球選手伊洛娜．馬赫在內的運動員質疑，她的BMI爲30，嚴格來說是達到肥胖門檻。伊洛娜在IG上回應羞辱她體重的酸民網友：「哎呀，我要參加奧運，但是你不行。」

Advocates for overweight individuals and people of color note that the formula was developed nearly 200 years ago and based exclusively on data from men, most of them white, and that it was never intended for medical screening.

過重者與有色人種的倡議人主張，該公式制定於近200年前，且數據僅來自男性，其中大部分爲白人，而且從來沒有打算用於疾病篩檢。

Even physicians have weighed in on the shortcomings of BMI. The American Medical Association warned last year that BMI is an imperfect metric that doesn’t account for racial, ethnic, age, sex and gender diversity. It can’t differentiate between individuals who carry a lot of muscle and those with fat in all the wrong places.

甚至醫師也開始討論BMI的缺點。美國醫學會去年警告，BMI是不完美的指標，其並未考慮種族、族羣、年齡、性別與性別多元化，也無法辨別個體是擁有大量肌肉，還是脂肪都囤積在錯誤的地方。

“Based on BMI, Arnold Schwarzenegger when he was a bodybuilder would have been categorized as obese and needing to lose weight,” said Dr. Wajahat Mehal, director of the Metabolic Health and Weight Loss Program at Yale University. “But as soon as you measured his waist, you’d see, ‘Oh, it’s 32 inches.’”

耶魯大學代謝健康與減重計劃主任梅哈爾醫師表示，「根據BMI，阿諾史瓦辛格還是健美選手時，會被歸類爲肥胖且需要減重，但只要測量他腰圍就會發現，哦，32英寸」。

So, welcome a new metric: the body roundness index. BRI is just what it sounds like — a measure of how round or circlelike you are, using a formula that takes into account height and waist, but not weight.

因此，歡迎新指標：身體圓度指數（BRI）。BRI顧名思義使用考慮身高與腰圍的公式，來測量你身形圓度或多圓，而不考慮體重。

It’s a formula that may provide a better estimate of central obesity and abdominal fat, which are closely linked to an increased risk of developing Type 2 diabetes, hypertension and heart disease, unlike fat stored on the buttocks and thighs.

該公式能更妥善評估中央型肥胖與腹部脂肪，這與第二型糖尿病、高血壓和心臟病風險增加高度相關，跟囤積在臀部與大腿的脂肪不一樣。

A paper published in JAMA Network Open in June was the latest study to report that BRI is a promising predictor of mortality. BRI scores generally run from 1 to 15; most people rank between 1 and 10.

根據六月發表在美國醫學會期刊網路開放版的一篇最新研究指出，BRI有望應用於預測死亡率。BRI評分1至15，大多數人介於1至10之間。

文／Roni Caryn Rabin　譯／江昱蓁