Table 1.

Standard fat-free mass index (FFMI) for males and females age 25-69 years old with body mass index (BMI) 18.5 to 30 for all race-ethnicity groups in the U.S. population. FFMI is in kg/m². The chart is used as follows: A 40 year old male starts a medical therapy with a FFMI of 19.631 and completes therapy with a FFMI of 18.668 denoting a 20 percentile drop in FFMI (60^th to 40^th). Outcomes could be stratified by percentile change in FFMI to determine the metabolic expense of the therapy or subsequently the effect of a nutritional intervention on outcomes. The same device would be necessary for both pre- and post-treatment measurements.

Centile	Male FFMI	Female FFMI	Centile	Male FFMI	Female FFMI	Centile	Male FFMI	Female FFMI
1%	15.278	13.544	34%	18.369	15.425	67%	19.936	16.536
2%	15.560	13.776	35%	18.411	15.461	68%	19.991	16.573
3%	15.751	13.944	36%	18.459	15.493	69%	20.039	16.602
4%	15.978	14.032	37%	18.506	15.523	70%	20.095	16.633
5%	16.168	14.123	38%	18.558	15.558	71%	20.165	16.685
6%	16.357	14.202	39%	18.612	15.589	72%	20.213	16.719
7%	16.465	14.267	40%	18.668	15.618	73%	20.267	16.763
8%	16.581	14.327	41%	18.706	15.644	74%	20.319	16.809
9%	16.692	14.393	42%	18.769	15.675	75%	20.378	16.868
10%	16.807	14.444	43%	18.809	15.703	76%	20.434	16.917
11%	16.924	14.509	44%	18.866	15.739	77%	20.486	16.958
12%	17.008	14.561	45%	18.902	15.786	78%	20.537	17.005
13%	17.116	14.596	46%	18.945	15.819	79%	20.599	17.062
14%	17.183	14.643	47%	18.997	15.851	80%	20.652	17.113
15%	17.241	14.688	48%	19.059	15.883	81%	20.719	17.161
16%	17.315	14.741	49%	19.107	15.924	82%	20.775	17.211
17%	17.378	14.779	50%	19.160	15.962	83%	20.834	17.259
18%	17.428	14.817	51%	19.204	15.991	84%	20.905	17.321
19%	17.496	14.867	52%	19.254	16.017	85%	20.966	17.367
20%	17.568	14.908	53%	19.302	16.046	86%	21.044	17.427
21%	17.638	14.950	54%	19.346	16.087	87%	21.139	17.477
22%	17.689	15.003	55%	19.386	16.126	88%	21.232	17.545
23%	17.773	15.036	56%	19.425	16.164	89%	21.324	17.600
24%	17.830	15.073	57%	19.478	16.195	90%	21.428	17.663
25%	17.891	15.110	58%	19.530	16.224	91%	21.537	17.733
26%	17.954	15.138	59%	19.579	16.255	92%	21.629	17.812
27%	17.992	15.175	60%	19.631	16.287	93%	21.740	17.918
28%	18.046	15.210	61%	19.669	16.328	94%	21.865	18.049
29%	18.114	15.250	62%	19.722	16.367	95%	22.013	18.162
30%	18.168	15.289	63%	19.762	16.405	96%	22.285	18.337
31%	18.224	15.316	64%	19.799	16.430	97%	22.522	18.512
32%	18.277	15.356	65%	19.847	16.463	98%	22.826	18.680
33%	18.322	15.394	66%	19.894	16.498	99%	23.492	19.017