体重指数是一个以身高与体重为基础计算出的比值，其正常范围通常在18和25之间，超过25为超重，超过30即为肥胖。

BMI is a calculation of height to weight, and the normal range is usually considered to be 18 to 25, with more than 25 considered overweight and above 30 obese.

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体质指数是一个考虑到身高和体重的比值。

The index is a ratio that takes into account height and weight.

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目的用经典的双生子设计探讨遗传因素和环境因素对青少年身高、体重、体质指数(BMI)、腰围、腰臀围比值(WHR)等体型指征相关指标的影响程度。

Objective To investigate the impact of inheritance on height, weight, body mass index (BMI), waist circumference and waist-hip ratio (WHR) in adolescent by the classic twin design.

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