Table 1: Characteristics of infants in the Okinawan village, Japan.

Cross sectional survey3–5 months6–12 months16–23 months

𝑛 942898980
Male (%)471 (50%)443 (49.3%)478 (48.8%)
Mean birth weight ± SD g 3 0 2 6 ± 4 2 5 2 9 9 3 ± 4 3 8 2 9 9 9 ± 4 4 2
Mean gestational age ± SD week 3 8 . 9 ± 1 . 7 3 8 . 8 ± 1 . 8 3 8 . 8 ± 1 . 7
Mean maternal age ± SD years 2 9 . 7 ± 5 . 4 3 0 . 3 ± 5 . 4 3 1 . 2 ± 3 . 5
Mean Hb ± SD g/L 1 2 1 ± 1 1 1 2 0 ± 1 1 1 2 4 ± 9
Birth order (%)
 1441 (46.8%)431 (48.0%)442 (45.1%)
 2284 (30.1%)271 (30.2%)284 (29.0%)
 3217 (23.1%)196 (21.8%)254 (25.9%)
Feeding method at screening (%)
 Breast-fed237 (25.2%)151 (16.8%)
 Mixed-fed334 (35.5%)158 (17.6%)
 Formula-fed371 (39.4%)589 (65.5%)

Cohort study

n511
Male (%)237 (46.4%)
Mean birth weight ± SD g 3 0 2 3 ± 4 2 9
Mean gestational age ± SD week 3 8 . 8 ± 1 . 7
Mean maternal age ± SD years 3 0 . 1 ± 5 . 5
Mean Hb ± SD g/L 1 2 1 ± 1 0 1 2 0 ± 1 1 1 2 5 ± 9
Birth order (%)
 1252 (49.3%)
 2142 (30.1%)
 3117 (22.9%)
Feeding method at screening (%)
 Breast-fed109 (21.3%)79 (15.5%)
 Mixed-fed210 (41.1%)80 (15.7%)
 Formula-fed192 (37.6%)352 (68.9%)