Expanded Normal Weight Obesity and Insulin Resistance in US Adults of the National Health and Nutrition Examination Survey

Table 5

Mean HOMA-IR values across body fat percentage quintiles, with and without control of the covariates.

Variable controlled	Body fat percentage quintiles^§					F
	Quintile 1; mean ± SE	Quintile 2; mean ± SE	Quintile 3; Mean ± SE	Quintile 4; mean ± SE	Quintile 5; mean ± SE
None	0.99 ± 0.03^a	1.55 ± 0.5^b	2.16 ± 0.07^c	2.60 ± 0.07^d	3.92 ± 0.17^e	451.61	<0.0001
Demographics	0.98 ± 0.45^a	1.59 ± 0.07^b	2.24 ± 0.08^c	2.72 ± 0.08^d	4.06 ± 0.15^e	448.21	<0.0001
Demographics and lifestyle^†	1.01 ± 0.05^a	1.60 ± 0.07^b	2.25 ± 0.08^c	2.71 ± 0.08^d	4.04 ± 0.15^e	511.33	<0.0001
Demographics, lifestyle, BMI5	1.80 ± 0.07^a	2.10 ± 0.08^b	2.38 ± 0.08^c	2.34 ± 0.07^c	2.91 ± 0.11^d	68.83	<0.0001

^§Body fat percentage quintiles are sex-specific. For each quintile, n represents the unweighted sample size and the percentage reflects the weighted proportion of the sample in that quintile, which represents the US adult population: Q1 (; 19.8%), Q2 (; 20.0%), Q3 (; 19.9%), Q4 (; 20.0%), and Q5 (; 20.3%). Total . Demographic covariates included age, sex, race, and year of assessment. ^†Lifestyle covariates included moderate physical activity, vigorous physical activity, and smoking. Means on the same row have been adjusted for differences in the covariates listed in the first column. BMI5 represents the variable, body mass index, divided into sex-specific quintiles. ^a,b,c,d,eMeans on the same row with the same superscript letter are not significantly different.