Waist circumference is a critical indicator of health risk validated by numerous studies over the years (Ross et al., 2020). Maintaining a healthy waist circumference is essential in reducing the risk of various conditions such as cardiovascular disease (Hu et al., 2004), type 2 diabetes (Siren et al., 2012), and certain cancers (Moore et al., 2004; Staiano et al., 2012).

Beyond the Basics: Waist-to-Height Ratio
Different variations of the waist circumference indicators have been tried and developed recently, namely the waist-to-height ratio which has now been recommended by the National Institute of Clinical Excellence (NICE) in the United Kingdom to be used alongside BMI when measuring obesity. The waist-to-height ratio is calculated by dividing your waist circumference by your height. If your waist circumference is more than half your height, you may have an increased risk of health problems.
Measuring Up: How to Check Your Waist Circumference
The World Health Organization (WHO) also provides guidelines for how to manually measure waist circumference as a way to assess abdominal obesity and its associated health risks. These guidelines are outlined below:
The waist circumference is measured at the midpoint between the bottom of the rib cage and the top of the hip. The measurement should be taken in a standing position, with the feet close together, and the arms relaxed at the sides.
The tape should be placed around the abdomen at the level of the waistline, making sure that it is snug but not compressing the skin.
The measurement should be taken to the nearest 0.1 cm
The measurement process should then be repeated.
However, manual measurement alone does have some limitations, such as the possibility of human error and the inability of a tape measure to accurately follow the curve of the spine or the small of the back. It can also be a lengthy and invasive process for the person being measured.
Enter the Digital Age: the Body Volume Index API
In recent years, digital measurement tools such as those provided by using the Body Volume Index API have been developed to overcome these limitations. The API allows measurements to be captured digitally while adhering to WHO standards, making the process far quicker and eliminating the need for the close personal contact that is needed for manual measurements. Additional data alongside waist circumference and waist-to-height ratio, such as waist-to-hip ratio and body composition data can also be collected from the same two digital images sent to the API.

Conclusion
In conclusion, waist circumference is a crucial health indicator that should be measured regularly and accurately. Manual measurements are effective but have limitations, while digital measurement tools such as the Body Volume Index API provide a faster, less invasive, and more accurate way of measuring waist circumference.
The waist-to-height ratio is also an essential indicator of health risk that should be considered alongside BMI when measuring obesity. By monitoring your waist circumference and maintaining a healthy lifestyle, you can reduce the risk of various health conditions and improve your overall health and well-being.
References
Hu, G., Tuomilehto, J., Silventoinen, K., Barengo, N., & Jousilahti, P. (2004). Joint effects of physical activity, body mass index, waist circumference and waist-to-hip ratio with the risk of cardiovascular disease among middle-aged Finnish men and women. European heart journal, 25(24), 2212-2219. Moore, L. L., Bradlee, M. L., Singer, M. R., Splansky, G. L., Proctor, M. H., Ellison, R. C., & Kreger, B. E. (2004). BMI and waist circumference as predictors of lifetime colon cancer risk in Framingham Study adults. International journal of obesity, 28(4), 559-567. Siren, R., Eriksson, J. G., & Vanhanen, H. (2012). Waist circumference a good indicator of future risk for type 2 diabetes and cardiovascular disease. BMC public health, 12(1), 1-6. Staiano, A. E., Reeder, B. A., Elliott, S., Joffres, M. R., Pahwa, P., Kirkland, S. A., ... & Katzmarzyk, P. T. (2012). Body mass index versus waist circumference as predictors of mortality in Canadian adults. International journal of obesity, 36(11), 1450-1454. Ross, R., Neeland, I. J., Yamashita, S., Shai, I., Seidell, J., Magni, P., ... & Després, J. P. (2020). Waist circumference as a vital sign in clinical practice: a Consensus Statement from the IAS and ICCR Working Group on Visceral Obesity. Nature Reviews Endocrinology, 16(3), 177-189.