Table 1

Demographic and Basic Characteristics of Children and Adolescents From NHANES 2005-2006

Characteristic	Children, 6-12 y (n = 860)	Adolescents, 13-19 y (n = 1,142)	P Value
Demographic
Age, weighted mean (SE), y	8.99 (0.08)	15.82 (0.13)
BMI, z score, weighted mean (SE)^a	0.483 (0.114)	0.533 (0.054)	.728
Sex, weighted %			.208
Male	52.5	47.0
Female	47.5	53.0
Race, weighted %			.381
Mexican American	14.2	11.1
Other Hispanic	2.4	2.5
White	59.6	65.8
Black	15.0	14.9
Other	8.7	5.8
Asthma history, weighted %			.776
Yes	18.4	19.6
No	81.6	80.4
Current asthma, weighted %			.544
Yes	14.3	12.6
No	85.7	87.4
Lifestyles
Smoking, weighted %			<.001b
Smoking	0.3	27.7
Nonsmoking	99.7	72.3
Secondhand smoke exposure, weighted %			.002^b
Yes	11.7	19.3
No	88.3	80.7
Number of smokers at home,			.021^b
weighted %
0	88.8	80.8
1	5.5	7.6
2	5.1	9.8
3	0.6	1.8
MET score, weighted mean (SE)c	…	3,863.78 (337.11)	NA
Dietary nutrients, weighted
mean (SE)
Sodium,mg	3,013.42 (61.66)	3,560.90 (96.82)	<.001^b
Total sugar, g	133.09 (3.35)	150.61 (3.83)	.003^b
Vitamin A, mg	612.00 (32.95)	576.77 (25.85)	.257
Vitamin C, mg	76.49 (3.26)	88.69 (3.98)	.027^b
Vitamin E, mg	5.72 (0.23)	6.70 (0.30)	.017^b
Vitamin B₆, mg	1.63 (0.05)	1.96 (0.06)	<.001^b
Vitamin B₁₂, mg	4.77 (0.22)	5.73 (0.26)	.021^b
Fiber, g	13.41 (0.40)	13.76 (0.53)	.383
Folate, mg	373.58 (10.65)	408.46 (13.21)	.014^b
Laboratory measures
C-reactive protein, weighted	0.29 (0.10)	0.17 (0.02)	.219
mean (SE), mg/dL
Serum vitamin D level,			<.001^c
weighted %^c
Sufficiency	83.2	70.4
Insufficiency	15.9	23.1
Deficiency	0.9	6.5
Allergic symptom, weighted %			.108
Yes	37.4	42.7
No	62.6	57.3
Allergic sensitization, weighted %			.135
Yes	40.0	43.9
No	60.0	56.1

BMI = body mass index; MET = metabolic equivalent of task; NA = not available.
Note: Data were weighted according to the National Health and Nutrition Examination Survey protocol.
↵a BMI for age charts.
↵b Significant difference between the 2 groups.
↵c For participants aged 12 years or older.