Table 1.
Baseline characteristics and average 4-year lifestyle changes and changes in nut consumption among 126 190 US women and men in three prospective cohorts
| HPFS (n=27 521) | NHS (n=61 680) | NHS II (n=55 684) | ||||
| Variables | Baseline | Changes within each 4-year period | Baseline | Changes within each 4-year period | Baseline | Changes within each 4- year period |
| Age (years)* | 52 (7.6) | 53 (6.9) | 39 (5.2) | |||
| Sleep (hours/day)† | 7.0 (1.0) | 7.0 (1.0) | 6.0 (1.1) | |||
| Weight (kg) | 83 (12) | 0.8 (4.0) | 68 (14) | 1.1 (5.0) | 69 (16) | 1.8 (6.3) |
| BMI (kg/m2) | 26 (3.3) | 0.2 (1.4) | 25 (4.7) | 0.4 (1.9) | 25 (5.7) | 0.7 (2.3) |
| Calorie (kcal) | 2011 (612) | −6.0 (510) | 1768 (525) | −2.0 (449) | 1763 (542) | −8.0 (491) |
| Alcohol (g/day) | 12 (15) | 0.4 (10) | 6.1 (11) | −0.1 (7.0) | 3.4 (6.7) | 0.6 (6.5) |
| Physical activity (MET hours/week)‡ |
20 (26) | 0.8 (23) | 14 (21) | 1.5 (24) | 22 (32) | −0.2 (27) |
| Smoking status | ||||||
| Never | 48% | 44% | 64% | |||
| Former smoker | 40% | 36% | 23% | |||
| Current smoker | 8.6% | 20% | 13% | |||
| Fruits (servings/day) | 1.5 (1.2) | 0.1 (1.1) | 1.7 (1.2) | 0.0 (1.1) | 1.2 (1.0) | 0.1 (1.0) |
| Vegetables (servings/day) | 3.0 (1.8) | 0.2 (1.8) | 3.8 (2.2) | 0.0 (1.9) | 3.4 (2.2) | 0.1 (2.1) |
| Whole grains (servings/day) | 1.5 (1.4) | 0.3 (2.5) | 1.2 (1.1) | 0.1 (1.1) | 1.1 (1.1) | 0.0 (1.1) |
| Red meat (servings/day) | 0.6 (0.5) | −0.0 (0.4) | 0.8 (0.4) | 0.0 (0.3) | 0.6 (0.4) | 0.0 (0.4) |
| AHEI score, excluding nuts | 43 (10) | 1.6 (7.2) | 43 (9.9) | 1.3 (7.6) | 42 (10) | 2.2 (8.7) |
| Nut consumption (servings/day) | ||||||
| Total nuts | 0.3 (0.5) | 0.1 (0.5) | 0.2 (0.3) | 0.0 (0.3) | 0.1 (0.2) | 0.1 (0.4) |
| Tree nuts | 0.2 (0.3) | 0.1 (0.3) | 0.1 (0.2) | 0.0 (0.2) | 0.1 (0.1) | 0.0 (0.2) |
| Peanuts | 0.1 (0.3) | 0.0 (0.3) | 0.1 (0.2) | 0.0 (0.2) | 0.1 (0.1) | 0.1 (0.3) |
| Peanut butter | 0.2 (0.4) | 0.0 (0.4) | 0.2 (0.3) | 0.0 (0.3) | 0.2 (0.3) | 0.0 (0.3) |
| HPFS ( n = 14 333 ) | NHS ( n = 28 175 ) | NHS II ( n = 46 072 ) | ||||
| Walnut and other tree nut consumption (servings/day)§ | ||||||
| Walnuts | 0.0 (0.1) | 0.0 (0.2) | 0.0 (0.1) | 0.0 (0.1) | 0.0 (0.1) | 0.0 (0.2) |
| Other tree nuts (without walnuts) | 0.1 (0.3) | 0.1 (0.3) | 0.1 (0.2) | 0.1 (0.2) | 0.1 (0.2) | 0.1 (0.3) |
*Value is not age adjusted. Baseline values are means (SD) standardised to the age distribution of the study population. Data are based on 24 years of follow-up (1986–2010) of the HPFS and the NHS and 20 years of follow-up (1991–2011) of the NHS II. Changes within each 4-year period are means (SD) or %.
†Data on average duration of sleep per 24 hour period was first available in 1987 in HPFS, in 1986 in the NHS and in 2001 in the NHS II.
‡Physical activity was assessed by means of validated questionnaires with average energy expenditure (MET hours/week) for specific activities).
§Data on walnuts and other tree nuts were first available in 1998 in NHS, 1998 in HPFS and 1999 in NHS II. Tree nut consumption was the sum of other tree nuts and walnuts (if available). Total nut consumption was the sum of peanuts, tree nuts and walnuts (if available).
¶
AHEI, Alternate Health Eating Index; BMI, body mass index; HPFS, Health Professionals Follow-up Study; MET, metabolic equivalent; NHS, Nurses' Health Study.