Table 1. Basic characteristics of participants according to quartile (Q) of diet-related GHGE (g CO2-eq/day) among 392 Japanese adultsa.
| All (n = 392) | Q1 (n = 98) | Q2 (n = 98) | Q3 (n = 98) | Q4 (n = 98) | Pc | |
|---|---|---|---|---|---|---|
| 3241 (2992, 3550)b | 3757 (3450, 4044)b | 4191 (3844, 4511)b | 4833 (4420, 5198)b | |||
| Age (years) | 44.5 ± 13.4 | 39.6 ± 13.1* | 44.9 ± 13.6†‡ | 44.1 ± 13.1*† | 49.4 ± 11.9‡ | <.0001 |
| Body mass index (kg/m2) | 23.3 ± 3.6 | 23.0 ± 3.8 | 23.6 ± 4.0 | 22.9 ± 3.1 | 23.7 ± 3.6 | 0.39 |
| Living area (%) | 0.02 | |||||
| Hokkaido and Tohoku | 15.1 | 21.4 | 18.4 | 7.1 | 13.3 | |
| Kanto | 20.2 | 20.4 | 24.5 | 22.4 | 13.3 | |
| Hokuriku and Tokai | 9.4 | 10.2 | 10.2 | 12.2 | 5.1 | |
| Kinki | 15.1 | 13.3 | 7.1 | 16.3 | 23.5 | |
| Chugoku and Shikoku | 20.2 | 18.4 | 23.5 | 21.4 | 17.3 | |
| Kyusyu and Okinawa | 20.2 | 16.3 | 16.3 | 20.4 | 27.6 | |
| Occupation (%) | 0.003 | |||||
| Clerical | 41.8 | 35.7 | 40.8 | 49.0 | 41.8 | |
| Nursing care | 41.8 | 52.0 | 41.8 | 33.7 | 39.8 | |
| Medical assistant | 3.1 | 2.0 | 0.0 | 9.2 | 1.0 | |
| Cooking assistant | 6.1 | 4.1 | 7.1 | 3.1 | 10.2 | |
| Others | 7.1 | 6.1 | 10.2 | 5.1 | 7.1 | |
| Educational background (%) | 0.82 | |||||
| Junior high school or other | 2.6 | 5.1 | 1.0 | 2.0 | 2.0 | |
| Senior high school | 26.5 | 26.5 | 27.6 | 26.5 | 25.5 | |
| Vocational school or junior college | 36.7 | 38.8 | 37.8 | 33.7 | 36.7 | |
| University or graduate school | 34.2 | 29.6 | 33.7 | 37.8 | 35.7 | |
| Smoking habit (%) | 0.70 | |||||
| Nonsmoker | 56.1 | 54.1 | 58.2 | 56.1 | 56.1 | |
| Past smoker | 18.1 | 15.3 | 15.3 | 19.4 | 22.4 | |
| Current smoker | 25.8 | 30.6 | 26.5 | 24.5 | 21.4 |
GHGE, greenhouse gas emissions; CO2-eq, carbon dioxide equivalents.
*†‡ Maen values within a row with different symbols were significantly different between the quartile group by post hoc Bonferroni’s test (P<0.05).
a Participants (196 men and 196 women) were divided into quartiles by usual diet-related GHGE separately by sex, and then combined for analysis. Usual diet-related GHGE was calculated using the Multiple Source Method [42, 43] and then adjusted for energy intake by residual method. Values are means ± SDs unless otherwise indicated.
b Usual diet-related GHGE (g CO2-eq/d): median (25th, 75th percentiles).
c Trend of association was examined for age and body mass index using a linear regression model with the median value of diet-related GHGE in each quartile as a continuous variable. χ2 test was used for categorical variables.