Table 2.

Effect of coffee consumption on serum thyroid function indicators.

Variable	Coffee	Beta	SE	t value	P
TSH	ref	ref	ref	ref	ref
	<2	-0.06	0.09	-0.62	0.54
	2-4	-0.23	0.07	-3.27	0.003 **
	>4	0.11	0.26	0.44	0.66
TT4	ref	ref	ref	ref	ref
	<2	-0.06	0.07	-0.77	0.45
	2-4	-0.07	0.08	-0.81	0.43
	>4	-0.06	0.10	-0.59	0.56
TT3	ref	ref	ref	ref	ref
	<2	-0.43	0.91	-0.47	0.64
	2-4	0.02	1.28	0.02	0.99
	>4	-0.67	1.25	-0.53	0.60
FT4	ref	ref	ref	ref	ref
	<2	-0.01	0.01	-1.44	0.16
	2-4	-0.01	0.01	-1.00	0.32
	>4	-0.01	0.01	-0.69	0.49
FT3	ref	ref	ref	ref	ref
	<2	-0.01	0.02	-0.60	0.56
	2-4	0.02	0.03	0.68	0.50
	>4	-0.02	0.02	-1.03	0.31

**Tips less than 0.05, **Tips less than 0.01, Models adjusted for age, sex, education, ethnicity, smoking, alcohol, DM, hypertension, hyperlipidemia, BMI, and urinary iodine concentration.