Fluoride exposure and sleep patterns among older adolescents in the United States: a cross-sectional study of NHANES 2015–2016

Table 1 Demographic characteristics according to study sample

	Overall sample	Plasma fluoride sample	Water fluoride sample^a
	n = 512 N = 13,503,522	n = 473 N = 12,531,822	n = 419 N = 11,577,700
Age; Mean (SE)	17.24 (0.03)	17.26 (0.04)	17.22 (0.04)
Ratio family income to poverty; Mean (SE)	2.55 (0.18)	2.52 (0.18)	2.64 (0.19)
Sex; N (%)
Male	6,627,073 (49.08)	6,210,909 (49.56)	5,810,794 (50.19)
Female	6,876,449 (50.92)	6,320,912 (50.44)	5,766,905 (49.81)
Race/ethnicity; N (%)
Mexican American	2,142,458 (15.87)	2,117,863 (16.90)	1,701,676 (14.70)
Other Hispanic	880,521 (6.52)	859,924 (6.86)	632,563 (5.46)
Non-Hispanic White	7,387,374 (54.71)	6,800,039 (54.26)	6,696,365 (57.84)
Non-Hispanic Black	1,734,001 (12.84)	1,491,071 (11.90)	1,449,755 (12.52)
Non-Hispanic Asian	702,796 (5.20)	639,594 (5.10)	553,402 (4.78)
Other Race, including Multi-Racial	656,373 (4.86)	623,330 (4.97)	543,938 (4.70)
BMI categories; N (%)^b
Underweight	529,432 (3.94)	515,275 (4.14)	470,519 (4.09)
Normal weight	7,428,420 (55.32)	6,734,756 (54.07)	6,351,579 (55.15)
Overweight	2,780,123 (20.70)	2,562,271 (20.57)	2,458,759 (21.35)
Obese	2,690,339 (20.03)	2,644,312 (21.23)	2,235,201 (19.41)

Note. Sampling weights were applied for calculation of demographic descriptive statistics and therefore Ns for frequencies represent the weighted sample size. Re-weighting for the water fluoride sample was not applied for the calculation of descriptive statistics above.^a Participants who reported that they did not drink the tap water were excluded; ^b n = 507 for entire sample, n = 468 for plasma F sample and n = 415 for water F subsample due to missing data for this variable

ISSN: 1476-069X