A PRISMA-Driven Systematic Review of Predictive Equations for Assessing Fat and Fat-Free Mass in Healthy Children and Adolescents Using Multicomponent Molecular Models as the Reference Method

Table 1

Age- and sex-specific constants for conversion of body density, water, and mineral to %FM in children and youth.

Age (years)		Females			Males
	𝐷FFM	𝐶1	𝐶2	𝐷FFM	𝐶1	𝐶2
7–9	1.079	5.451	5.052	1.081	5.400	4.996
9–11	1.082	5.376	4.968	1.084	5.327	4.914
11–13	1.086	5.279	4.861	1.087	5.255	4.835
13–15	1.092	5.141	4.708	1.094	5.098	4.660
15–17	1.094	5.098	4.660	1.096	5.055	4.612
17–20	1.095	5.076	4.636	1.099	5.002	4.554
20–25	1.096	5.055	4.612	1.100	4.971	4.519

%FM: percent fat mass; Db: body density; 𝐷_FFM: fat-free mass density; 𝐶1: constant 1; 𝐶2: constant 2.
∗Calculation of percent fat mass (%FM) using age- and sex-specific values for the density of the FFM: %FM = [(𝐶1/Db) −𝐶2] * 100, where Db represents body density. Adapted from Lohman [10].