TABLE 2.

Mean weight gain (kg) above baseline weight in 1986 for each sleep duration category relative to the gain in those sleeping 7 hours, Nurses’ Health Study, 1986–2002

	Sleep duration (hours/24-hour period)
	≤5		6		7	8		≥9
	Mean	95% confidence interval	Mean	95% confidence interval	Mean	Mean	95% confidence interval	Mean	95% confidence interval
Age-adjusted model
1990	0.34	0.10, 0.57	0.21	0.10, 0.32	0.00	0.00	−0.12, 0.11	−0.06	−0.29, 0.17
1994	0.69	0.38, 1.00	0.26	0.11, 0.41	0.00	0.01	−0.14, 0.17	0.19	−0.12, 0.50
1998	0.96	0.52, 1.39	0.50	0.29, 0.70	0.00	0.00	−0.21, 0.21	0.18	−0.23, 0.60
2002	0.94	0.28, 1.59	0.67	0.37, 0.97	0.00	−0.05	−0.35, 0.26	0.45	−0.16, 1.05
Age- and body mass   index-adjusted model
1990	0.52	0.28, 0.75	0.29	0.17, 0.40	0.00	0.00	−0.11, 0.12	0.01	−0.21, 0.24
1994	0.74	0.43, 1.06	0.28	0.13, 0.43	0.00	0.01	−0.14, 0.17	0.20	−0.10, 0.51
1998	1.02	0.59, 1.45	0.51	0.30, 0.71	0.00	−0.01	−0.21, 0.20	0.22	−0.19, 0.64
2002	1.14	0.49, 1.79	0.71	0.41, 1.00	0.00	−0.06	−0.36, 0.24	0.49	−0.11, 1.09
Fully adjusted model*
1990	0.41	0.17, 0.64	0.23	0.12, 0.35	0.00	0.03	−0.09, 0.14	0.04	−0.19, 0.27
1994	0.59	0.28, 0.91	0.20	0.05, 0.35	0.00	0.06	−0.09, 0.21	0.26	−0.04, 0.57
1998	0.78	0.34, 1.21	0.38	0.18, 0.58	0.00	0.05	−0.16, 0.26	0.27	−0.14, 0.68
2002	0.78	0.13, 1.44	0.53	0.23, 0.82	0.00	0.02	−0.29, 0.32	0.51	−0.09, 1.11

^*Fully adjusted model adjusted for age, baseline body mass index, smoking, alcohol consumption, caffeine intake, spousal level of education, medication use, menopausal status, snoring status, shift-working history, physical activity, total caloric intake, dietary fiber, ratio of polyunsaturated to saturated fat, trans-fat intake, and servings of fruits and vegetables.