Table 1.

Age-standardized Baseline Characteristics of the Women From the Nurses’ Health Study (1984–2000, n = 71,365) and of the Men From the Health Professionals Follow-up Study (1986–1998, n = 40,215), According to Quintiles of Total Fiber Intake

	Women (n = 71,365)						Men (n = 40,215)
	Quintile 1	Quintile 2	Quintile 3	Quintile 4	Quintile 5	P Value	Quintile 1	Quintile 2	Quintile 3	Quintile 4	Quintile 5	P Value
No.	13,987	14,291	14,537	14,383	14,167		8,210	7,899	8,127	8,051	7,928
Age, years (mean (SD))	49.2 (7.0)	49.6 (7.1)	50.2 (7.1)	50.8 (7.1)	51.8 (7.1)	<0.001	51.4 (9.1)	52.1 (9.2)	52.7 (9.3)	53.0 (9.4)	53.7 (9.5)	<0.001
Smoking habits, %
Never smokers	37	42	45	48	52		43	46	48	51	54
Former smokers	37	39	40	40	39	<0.001	42	43	43	43	41	<0.001
Current smokers	26	19	15	12	9		15	11	9	6	5
Pack-years among ever smokersa,b	27	24	22	20	18	<0.001	23	21	20	19	17	<0.001
Body mass index, kg/m2	24.9	25.0	25.0	25.0	24.8	<0.001	25.7	25.6	25.4	25.3	25.1	<0.001
US region, %
New England	15	15	15	14	13		22	22	21	20	21
Mid-Atlantic	44	43	43	43	44		16	16	17	17	16
East North Central	19	20	19	18	18	<0.001	20	20	19	21	21	<0.001
South Atlantic	6	6	6	6	6		35	35	36	35	35
West South Central	5	5	5	5	5		1	1	1	1	1
Pacific	11	11	12	14	14		5	5	6	6	6
Physician examination, %
No physician visits	15	12	11	11	10		24	22	21	20	19
Screening visits	17	17	17	18	18	<0.001	15	16	16	17	17	<0.001
Symptom-related visits	68	70	71	71	72		61	62	63	64	64
Physical activity, MET-hours/weekc	11.0	12.6	13.7	15.2	18.9	<0.001	23.0	23.9	24.3	26.1	31.3	<0.001
Total energy, kcal/day	1,311	1,564	1,731	1,914	2,185	<0.001	1,493	1,775	1,968	2,180	2,533	<0.001
Diabetes, %	3.0	3.1	3.6	3.6	3.9	<0.001	2.6	3.0	3.3	3.4	3.7	<0.001
Dietary intake
Total fiber, g/day	10.2	13.9	16.8	20.1	26.6	<0.001	11.3	15.9	19.5	23.8	33.3	<0.001
Cereal fiber	2.5	3.6	4.4	5.3	7.0	<0.001	3.0	4.4	5.5	6.8	9.5	<0.001
Fruit fiber	1.8	2.7	3.5	4.4	6.3	<0.001	2.0	3.0	3.9	5.0	7.5	<0.001
Vegetable fiber	4.0	5.3	6.2	7.4	9.9	<0.001	3.9	5.3	6.4	7.8	10.9	<0.001
Omega-3, g/day	0.10	0.10	0.10	0.11	0.11	<0.001	0.14	0.14	0.14	0.14	0.15	<0.001
Cured meat, servings/day	0.28	0.31	0.32	0.33	0.31	<0.001	0.34	0.37	0.37	0.37	0.34	<0.001

Abbreviations: MET, metabolic equivalent; SD, standard deviation.

^aAge-adjusted mean (all such values).

^bNo. of packs smoked per day × no. of years smoked, among past and current smokers.

^cMET-hours/week are the sum of the average time per week spent in each activity × the MET value of each activity.