Development of an Easy-to-Use Prediction Equation for Body Fat Percentage Based on BMI in Overweight and Obese Lebanese Adults

Abstract

An accurate estimation of body fat percentage (BF%) in patients who are overweight or obese is of clinical importance. In this study, we aimed to develop an easy-to-use BF% predictive equation based on body mass index (BMI) suitable for individuals in this population. A simplified prediction equation was developed and evaluated for validity using anthropometric measurements from 375 adults of both genders who were overweight or obese. Measurements were taken in the outpatient clinic of the Department of Nutrition and Dietetics at Beirut Arab University (Lebanon). A total of 238 participants were used for model building (training sample) and another 137 participants were used for evaluating validity (validation sample). The final predicted model included BMI and sex, with non-significant prediction bias in BF% of −0.017 ± 3.86% (p = 0.946, Cohen’s d = 0.004). Moreover, a Pearson’s correlation between measured and predicted BF% was strongly significant (r = 0.84, p < 0.05). We are presenting a model that accurately predicted BF% in 61% of the validation sample with an absolute percent error less than 10% and non-significant prediction bias (−0.028 ± 4.67%). We suggest the following equations: BF% females = 0.624 × BMI + 21.835 and BF% males = 1.050 × BMI − 4.001 for accurate BF% estimation in patients who are overweight or obese in a clinical setting in Lebanon.

Development and Validation of a Simple Equation to Predict Fat-Free Mass in the Adult Population

“…Lyra et al ( 12 ) conducted a study to obtain the FFM predictive equation in 218 Brazilian adolescents aged 10 to 16 yr with healthy weight based on body circumferences. The significant drawbacks of this study were the lack of a validation group and the lack of using height, weight, and BMI variables in designing the estimation equation, although these independent variables have a high correlation coefficient with FFM ( 10 , 11 ). It is also developed for normal-weight adolescents, so it may not be generalizable to other age groups.…”

“…Twelve subjects (seven men and five women) were excluded from the study based on the exclusion criteria. Study subjects were randomly divided into two subgroups of derivation and validation; the derivation group included two-thirds of the total samples, and the validation group included one-third of the total ( 10 , 11 ). Afterward, the FFM predictive equation was derived from the derivation group and then validated in the second group.…”

Association between Dietary Practice and Gait Speed in Community-Dwelling Older Adults with Overweight and Obesity: A Cross-Sectional Study

“…A multi-frequency Bioelectrical Impedance Analyzer (BIA) (MC-780MA, Tanita Corp., Tokyo, Japan) was used to measure performance in the morning by the same operator (the dietitian involved in this study); segmental and total body composition measurements [ 25 ], according to a standardized protocol [ 24 ], were taken as follows: First, information (i.e., age, sex, and height) of participants was entered into the device [ 26 ]. Next, participants were instructed to stand in a stable, barefoot position.…”

“…Next, participants were instructed to stand in a stable, barefoot position. Separate readings for different body regions (i.e., trunk, legs, and arms) were obtained based on an algorithm incorporating impedance, age, and height to estimate total body fat (BF), fat-free mass (FFM), and total body water (TBW) [ 26 ]. Participants adhered to all the protocol recommendations for correct BIA measurement, e.g., taking measurements more than three hours (3 h) after waking, urinating before measurements were taken, avoiding food and drink for at least 8 h beforehand, avoiding strenuous exercise, alcohol, and energy drinks for 12 h beforehand, and not having any metal objects or pacemakers.…”

The Relationship between Body Composition and ECG Ventricular Activity in Young Adults

“…Bioelectrical impedance analysis (BIA) is a widespread method for the reliable determination of body composition in laboratory and/or field conditions, with small intra- and interobserver variability [ 2 ]. The method is focused on measuring the human body’s resistance to a very small alternating electrical current based on equations to predict the amount of total body water, fat-free mass, and fat mass [ 3 , 4 ]. Thus, for a specific population, through precise formulas, we can calculate the lean and fat mass of the body, starting from the statistical associations based on biological relationships [ 3 ].…”