Table 2.

Characteristics of the enrolled subjects. BMI: body mass index.

		Non-Smoking Group (n = 13)	Smoking Group (n = 11)
age (year)		22 ± 2.1	21 ± 0.9
BMI (kg/m2)		20.9 ± 1.4	21.3 ± 2.1
a number of cigarette (number)		0	14 ± 5
nicotine (mg/a cigarette)		0	1.5 ± 2.0
tar (mg/a cigarette)		0	10.9 ± 3.9
Food Habit	1 meal	0	1
	2 meals	4	2
	3 meals	5	7
	much difference	2	3
caffeine intake	every day	2	5
	sometimes	3	6
	no intake	6	2
Sleeping time	less than 3 h	1	0
	4–6 h	4	2
	6–8 h	5	6

Table 2 shows characteristics of the enrolled subjects. There were no differences in characteristics and daily habits between the two groups.