Table 1.

Baseline age-standardized main characteristics of 4,306 women from the Swedish mammography cohort by tertiles of urinary fluoride ($n=\mathrm{4,306}$; mg/g creatinine) and by dietary fluoride ($n=\mathrm{4,072}$ mg/d).

Characteristics [continuous: mean ($\pm \text{SD}$), categorical: proportions ($n$)]	Tertiles of urinary fluoride			Tertiles of dietary fluoride
	1	2	3	1	2	3
Fluoride exposure (mg/g creatinine or mg/d)	0.7 ($\pm 0.2$)	1.1 ($\pm 0.1$)	1.9 ($\pm 3.1$)	1.3 ($\pm 0.3$)	2.1 ($\pm 0.2$)	3.2 ($\pm 0.9$)
$N$	1,436	1,435	1,435	1,358	1,357	1,357
Proportion of women receiving drinking water with fluoride concentration of $1\mathrm{mg}/\mathrm{L}$	76	93	94	73	96	98
Drinking water (glasses/d)a	3.1 ($2.2$)	3.8 ($\pm 2.4$)	4.2 ($\pm 2.7$)	2.6 ($\pm 1.6$)	3.8 ($\pm 1.7$)	5.3 ($\pm 2.7$)
Tea (cups/d)a	0.7 ($\pm 0.7$)	0.9 ($\pm 0.9$)	1.4 ($\pm 1.4$)	0.4 ($\pm 0.6$)	0.8 ($\pm 0.8$)	2.0 ($\pm 1.8$)
Coffee (cups/d)a	2.6 ($\pm 1.7$)	2.6 ($\pm 1.6$)	2.5 ($\pm 1.7$)	2.5 ($\pm 1.3$)	2.8 ($\pm 1.5$)	2.8 ($\pm 2.0$)
Age (y)	68 ($\pm 7$)	67 ($\pm 7$)	68 ($\pm 7$)	69 ($\pm 7$)	67 ($\pm 7$)	66 ($\pm 7$)
Education {y [% ($n$)]}
$<9$	25 (366)	24 (338)	21 (312)	25 (360)	24 (322)	21 (275)
10–11	38 (546)	38 (539)	40 (579)	40 (538)	39 (525)	37 (507)
$>12$	36 (520)	38 (553)	38 (542)	35 (459)	37 (506)	41 (570)
Missing	$<1$ (4)	$<1$ (5)	$<1$ (2)	$<1$ (1)	$<1$ (4)	$<1$ (5)
Height (cm)	164 ($\pm 6$)	164 ($\pm 6$)	163 ($\pm 6$)	164 ($\pm 6$)	164 ($\pm 6$)	164 ($\pm 6$)
Total fat mass (kg)	28 ($\pm 9$)	26 ($\pm 9$)	25 ($\pm 8$)	27 ($\pm 8$)	26 ($\pm 8$)	27 ($\pm 9$)
Missing [% ($n$)]	1 (14)	$<1$ (7)	1 (14)	1 (9)	1 (11)	1 (11)
Lean body mass (kg)	40 ($\pm 4$)	39 ($\pm 4$)	39 ($\pm 4$)	39 ($\pm 4$)	39 ($\pm 4$)	40 ($\pm 4$)
Missing [% ($n$)]	1 (14)	$<1$ (7)	1 (14)	1 (9)	1 (11)	1 (11)
Parity ($n$ children)	2 ($\pm 1$)	2 ($\pm 1$)	2 ($\pm 1$)	2 ($\pm 1$)	2 ($\pm 1$)	2 ($\pm 1$)
Smoking status [% ($n$)]
Never	51 (739)	51 (726)	51 (728)	54 (751)	49 (661)	51 (675)
Former	35 (498)	36 (512)	35 (498)	33 (428)	37 (502)	36 (497)
Current	8 (117)	8 (116)	10 (143)	7 (102)	8 (118)	10 (132)
Missing	6 (82)	6 (81)	5 (66)	6 (77)	6 (76)	4 (53)
Physical activity [% ($n$)]
Walk/bike $\ge 40\text{\hspace{0.17em}min}/\mathrm{d}$	34 (484)	39 (560)	42 (602)	36 (480)	37 (508)	42 (579)
Walk/bike $<40\text{\hspace{0.17em}min}/\mathrm{d}$	62 (889)	56 (807)	54 (773)	60 (812)	59 (805)	53 (723)
Walk/bike missing	4 (63)	5 (68)	4 (60)	5 (66)	4 (44)	4 (55)
Exercise $\ge 1\mathrm{h}/\mathrm{wk}$	74 (1,065)	78 (1,120)	78 (1,119)	78 (1,058)	80 (1,081)	79 (1,079)
Exercise $<1\mathrm{h}/\mathrm{wk}$	21 (297)	17 (245)	16 (238)	17 (226)	16 (218)	16 (217)
Exercise missing	5 (74)	5 (70)	5 (78)	5 (74)	3 (58)	5 (61)
Alcohol {g/d [% ($n$)]}
$\le 0.5$	12 (173)	13 (183)	14 (209)	14 (197)	13 (181)	14 (172)
0.5–15	72 (1,028)	73 (1,055)	73 (1,043)	76 (1,027)	76 (1,037)	77 (1,048)
$>15$	9 (132)	10 (143)	9 (135)	10 (134)	10 (139)	10 (137)
Missing	7 (103)	4 (54)	3 (49)	0 (0)	0 (0)	0 (0)
Prevalent diabetes [% ($n$)]
Yes	7 (95)	4 (60)	6 (92)	5 (1,286)	7 (1,268)	5 (1,289)
No	93 (1,341)	96 (1,375)	94 (1,343)	95 (72)	93 (89)	95 (68)
eGFR {${\mathrm{mL}/\mathrm{m}}^3\text{\hspace{0.17em}per\hspace{0.17em}}1.73{\mathrm{m}}^2$ [% ($n$)]}b
$>60$	87 (1,259)	90 (1,305)	90 (1,291)	89 (1,187)	90 (1,214)	89 (1,227)
59–30	12 (166)	9 (127)	9 (141)	10 (151)	10 (130)	10 (119)
$<30$	1 (11)	$<1$ (3)	$<1$ (3)	1 (10)	1 (2)	1 (4)
Missing	1 (9)	1 (9)	1 (10)	1 (10)	1 (11)	1 (7)
Urinary calcium (mg/g creatinine)	148 ($\pm 86$)	160 ($\pm 89$)	193 ($\pm 101$)	160 ($\pm 89$)	165 ($\pm 95$)	165 ($\pm 97$)
Dietary calcium (mg/d)	1,085 ($\pm 293$)	1,088 ($\pm 301$)	1,099 ($\pm 302$)	1,065 ($\pm 289$)	1,095 ($\pm 303$)	1,113 ($\pm 302$)
Missing [% ($n$)]	8 (115)	4 (62)	4 (58)	$<1$ (1)	0 (0)	0 (0)
Calcium supplement use [% ($n$)]
Yes	12 (175)	14 (203)	18 (251)	14 (200)	14 (191)	18 (238)
No	60 (861)	60 (871)	57 (812)	62 (829)	63 (863)	61 (837)
Missingc	28 (400)	25 (361)	26 (372)	23 (329)	22 (303)	21 (282)
Vitamin D supplement use [% ($n$)]
Yes	7 (100)	8 (113)	11 (152)	9 (123)	8 (111)	10 (131)
No	67 (958)	67 (958)	65 (931)	68 (917)	70 (957)	69 (958)
Missingc	26 (378)	25 (364)	24 (352)	23 (318)	21 (289)	21 (268)
Ever use of postmenopausal oral estrogen [% ($n$)]
Yes	58 (838)	63 (906)	64 (914)	59 (792)	64 (866)	63 (868)
No	39 (565)	35 (497)	34 (487)	38 (528)	34 (462)	35 (463)
Missingc	2 (33)	2 (32)	2 (34)	3 (38)	3 (29)	2 (26)
Ever use of corticosteroids [% ($n$)]
Yes	11 (160)	12 (178)	16 (227)	12 (160)	13 (173)	14 (192)
No	77 (1,109)	74 (1,066)	72 (1,031)	75 (1,019)	76 (1,026)	73 (998)
Missingc	12 (167)	13 (191)	12 (177)	13 (179)	12 (158)	12 (167)
Serum Beta-CrossLaps (ng/L)	441 ($\pm 189$)	467 ($\pm 186$)	492 ($\pm 204$)	461 ($\pm 193$)	466 ($\pm 193$)	465 ($\pm 197$)
Missing [% ($n$)]	$<1$ (6)	$<1$ (8)	$<1$ (7)	1 (7)	1 (8)	$<1$ (6)
BMD (${\mathrm{g}/\mathrm{cm}}^2$)
Spine	1.13 ($\pm 0.19$)	1.12 ($\pm 0.20$)	1.11 ($\pm 0.20$)	1.11 ($\pm 0.19$)	1.12 ($\pm 0.20$)	1.13 ($\pm 0.20$)
Femoral neck	0.87 ($\pm 0.12$)	0.87 ($\pm 0.12$)	0.86 ($\pm 0.13$)	0.86 ($\pm 0.12$)	0.87 ($\pm 0.12$)	0.87 ($\pm 0.13$)

Note: Continuous variables are presented as means ($\pm \text{standard deviation}$) and categorical as proportions ($n$). Means and proportions were age-standardized, according to seven quantiles of age at baseline. Data were complete for all observations unless otherwise indicated. BMD, bone mineral density; eGFR, estimated glomerular filtration rate; SD, standard deviation.

^aThe predefined volumes indicated in the questionnaire were $200\mathrm{mL}$ for water and $150\mathrm{mL}$ for coffee and tea.

^beGFR was assessed using the combined creatinine-cystatin C Chronic Kidney Disease Epidemiology Collaboration equation.

^cNonresponse was interpreted as no use in the analyses because of how the questionnaire was structured.