Table 1.
General characteristics of adults from the NDNS years 1 to 4 according to sleep duration category
| <7 Hours/day (SS) | Sleep categories 7–8 hours/day (RS) |
>8 Hours/day (LS) | Total | |
| Observations (n) | 539 | 788 | 285 | 1612 |
| Characteristics | Mean (95% CI) | Mean (95% CI) | Mean (95% CI) | Mean (95% CI) |
| Age (years) | 45 (44 to 46) | 44 (43 to 45) | 39 (38 to 40) | 43 (43 to 44) |
| BMI | 26 (25 to 27) | 25 (25 to 26) | 24 (23 to 25) | 25 (25 to 26) |
| Food energy | 1712 (1665 to 1758) | 1769 (1731 to 1807) | 1645 (1587 to 1703) | 1727 (1701 to 1752) |
| Equivalised household income | 33 000 (31 000 to 35 000) | 34 000 (32 000 to 36 000) | 29 000 (26 000 to 32 000) | 33 000 (32 000 to 34 000) |
| Fruit (g/day) | 98 (89 to 106) | 115 (107 to 124) | 82 (73 to 92) | 103 (98 to 108) |
| Vegetables (g/day) | 178 (168 to 188) | 194 (187 to 201) | 168 (157 to 180) | 185 (180 to 190) |
| Total FV (g/day) | 276 (261 to 291) | 309 (297 to 322) | 250 (233 to 267) | 287 (279 to 296) |
| Plasma vitamin C (µmol/L) | 48 (45 to 51) | 53 (51 to 55) | 56 (53 to 59) | 51 (50 to 53) |
| Plasma total carotenoids (µmol/L) | 2.2 (2.1 to 2.4) | 2.5 (2.4 to 2.7) | 2.4 (2.2 to 2.7) | 2.4 (2.3 to 2.5) |
| Plasma lycopene (µmol/L) | 0.62 (0.57 to 0.67) | 0.73 (0.69 to 0.77) | 0.69 (0.61 to 0.76) | 0.69 (0.66 to 0.72) |
| % (95% CI) | % (95% CI) | % (95% CI) | % (95% CI) | |
| Sex (female) | 55 (51 to 59) | 56 (52 to 59) | 64 (58 to 69) | 57 (55 to 60) |
| Ethnicity (white) | 92 (90 to 94) | 89 (86 to 91) | 88 (84 to 91) | 90 (89 to 92) |
| Has long-standing illness (yes) | 37 (33 to 41) | 30 (26 to 32) | 39 (33 to 45) | 34 (32 to 36) |
| Taking prescribed medicine (yes) | 47 (42 to 51) | 43 (38 to 46) | 53 (46 to 60) | 46 (43 to 49) |
| Employer (full-time or part-time employment) | 68 (64 to 72) | 72 (68 to 75) | 62 (56 to 67) | 69 (67 to 71) |
| SES (lower managerial and professional) | 28 (24 to 32) | 28 (25 to 31) | 22 (17 to 27) | 27 (24 to 29) |
| Smoking (never) | 51 (46 to 55) | 57 (53 to 60) | 54 (48 to 60) | 54 (52 to 57) |
| Consuming five or more portions of FV/day (yes) | 28 (24 to 32) | 35 (31 to 38) | 25 (21 to 31) | 31 (29 to 33) |
| Vegetarian (yes) | 2 (1 to 3) | 3 (2 to 4) | 0.7 (0.1 to 2) | 2 (1 to 3) |
| Has one child aged between 0 and 4 years | 15 (12 to 18) | 13 (10 to 15) | 12 (8 to 16) | 13 (12 to 15) |
| Frequency of drinking alcohol in past 12 months (once or two times in a week or month) | 45 (40 to 49) | 48 (44 to 51) | 50 (44 to 55) | 47 (45 to 50) |
BMI, body mass index; FV, fruit and vegetables; LS, long sleepers; NDNS, National Diet and Nutrition Survey; RS, reference sleepers; SES, socioeconomic status; SS, short sleepers.