[Estimation of the percentage of body fat based on the body mass index and the abdominal circumference: Palafolls Formula]. / Estimación del porcentaje de grasa corporal en función del índice de masa corporal y perímetro abdominal: fórmula Palafolls.

ABSTRACT

INTRODUCTION: Overweight and obesity have the features of a worldwide epidemic, making it a public health problem. The traditional classification with the body mass index is a good start, but after the evidence of the biochemical activities of adipose tissue, its measurement is a necessity. There are multiple formulas for this purpose, but with little possibility of applying it in Primary Care. The following formulas are proposed for its use in this setting; Men=(body mass index [BMI/Abdominal Circumference [AC]*10)+BMI. Women=([BMI/AC]*10)+BMI+10. MATERIAL AND METHODS: A descriptive, prospective study was conducted, including 505 women and 489 men aged between 30 and 90 years. Weight, height, and abdominal circumference were measured, and the body mass index, percentage of fat using the CUN BAE (Clínica Universidad de Navarra - Body Adiposity Estimator) and proposed formulas were calculated. RESULTS: Comparative calculations were made between CUN BAE and formulas. No significant differences were observed in the descriptive values (Women χ2=1.1; P=.89. Men χ2=0.8; P=.93. The confidence interval and standard error p=1. The numerical correlation shows r=0.94; p=0.0001; R2=0.89. The relative error of the mean in men was 5.48% and -0.43% in women. The comparison of medians demonstrated Wilcoxon=0.8333. The study of sensitivity and specificity for cut-off points shows a ROC curve AUC=0.986; P=<.0001. CONCLUSIONS: The lack of significant differences between the results of both formulas, makes it possible to be proposed for the calculation of the fat percentage in body weight in Primary Care Clinics.