TABLE 3—

Effects of Smoking, Supplement Use, and Ethnicity on Vitamin C Deficiency

	Serum Vitamin C Value
	<11 μmol/L, %	≥11 μmol/L, %	Odds Ratio (95% Confidence Interval)
Male
Smoking status
Nonsmokers (n = 4429)	11	89	1.0
Smokers (n = 2115)	31	69	3.6 (3.2, 4.1)
Supplement use
Yes (n = 2119)	7	93	1.0
No (n = 5226)	20	80	3.3 (2.8, 4.0)
Race/ethnicity
Non-Hispanic White (n = 2613)	16	84	1.0
Non-Hispanic Black (n = 2115)	19	81	1.2 (1.1, 1.5)
Mexican American (n = 2346)	13	87	0.83 (0.71, 0.97)
Female
Smoking status
Nonsmokers (n = 5776)	7	93	1.0
Smokers (n = 1686)	25	75	4.2 (3.6, 4.9)
Supplement use
Yes (n = 3204)	5	95	1.0
No (n = 5204)	14	86	3.1 (2.6, 3.7)
Race/ethnicity
Non-Hispanic White (n = 3039)	11	89	1.0
Non-Hispanic Black (n = 2605)	13	87	1.2 (1.0, 1.4)
Mexican American (n = 2379)	9	91	0.80 (0.66, 0.96)