Despite the ubiquity of the body mass index (BMI) in discourse on health, there is ambiguity in its use as a biomarker of current abnormality versus future risk. This distinction is consequential for knowledge of the relationship between body size and health, as well as for individuals deemed to have abnormal and ‘unhealthy’ bodies. Consequently, the purposes of this review are threefold. The first is to differentiate this ‘biomarker’ perspective from extant critiques of BMI as a proxy for health behaviours or as the defining characteristic of obesity as a disease. The second is to highlight the shift towards treating BMI as a measure of attained unhealthiness, rather than a probabilistic indicator of risk. Finally, rather than call for the abolition of BMI, this paper argues that its continued use as ‘just a number’ is in keeping with the push for weight neutrality in research and practice. The review concludes by demonstrating how the riskiness and unhealthiness of body size is conflated in public health messaging on COVID-19. BMI is a marker of risk, but its use as a surrogate for COVID-19 severity equates body size with health, shaping beliefs about vulnerability and personal responsibility amid an ongoing pandemic.

中文翻译：

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体重指数只是一个数字：在谈论身体尺寸时将风险和不健康混为一谈


尽管体重指数 (BMI) 在健康讨论中无处不在，但将其用作当前异常与未来风险的生物标志物仍存在模糊性。这种区别对于了解身体尺寸和健康之间的关系以及被认为具有异常和“不健康”身体的个人来说是很重要的。因此，本次审查的目的有三个。首先是将这种“生物标志物”观点与现有的对BMI作为健康行为的代表或作为肥胖作为疾病的定义特征的批评区分开来。第二个是强调将 BMI 作为衡量是否达到不健康程度的指标的转变，而不是作为风险的概率指标。最后，本文并没有呼吁废除体重指数，而是认为继续将其用作“只是一个数字”符合研究和实践中体重中立的推动。审查的结论是展示了体型的风险和不健康如何在有关 COVID-19 的公共卫生信息中混为一谈。 BMI 是风险标志，但将其用作 COVID-19 严重程度的替代指标，将体型与健康等同起来，从而在持续的大流行中塑造了关于脆弱性和个人责任的信念。