Table 4 Percentages of those who changed their frequency of physical activity or diet from 1991 (33 y) to 1999 (41 y) by social class, qualifications and BMI

From: Changes in diet and physical activity in the 1990s in a large British sample (1958 birth cohort)

    Activity Chips Fried food Fruit and salad
   aN 100% Increased nb=1281 (m) 1472 (f) Decreased nb=1377 (m) 1512 (f) Increased nb=733 (m) 845 (f) Decreased nb=1469 (m) 1448 (f) Increased nb=1365 (m) 1590 (f) Decreased nb=1341 (m) 1276 (f) Increased nb=1349 (m) 1426 (f) Decreased nb=1003 (m) 1206 (f)
Social class c           
Males           
 I and II   845 31 27 18 29 37 24 33 19
 III NM   457 29 32 15 34 35 27 29 23
 III M   2143 29 34 17 33 29 32 31 23
 IV and V   930 29 30 15 38 28 34 29 27
  P d   0.84 0.01 0.55 0.007 0.02 0.02 0.70 0.004
Females           
 I and II   850 32 32 22 21 45 17 31 24
 III NM   464 29 32 20 30 33 23 30 27
 III M   2335 32 32 16 32 32 29 30 25
 IV and V   1071 31 33 17 35 29 32 30 28
  P d   0.50 0.64 0.26 <0.0001 <0.0001 <0.0001 0.99 0.23
Education e           
 Males           
 Higher   1394 29 31 18 29 40 21 33 18
 A level   1138 31 33 16 35 30 30 34 21
 O level   1130 28 33 17 35 29 34 30 26
 <O level   583 29 32 14 38 23 39 25 31
 None   358 30 26 20 34 24 43 27 27
  P d   0.48 0.07 0.33 0.004 <0.0001 <0.0001 0.20 <0.0001
Females           
 Higher   1318 30 33 19 23 44 16 31 21
 A level   534 34 29 20 26 39 24 29 26
 O level   1827 33 33 16 33 31 29 31 26
 <O level   820 30 31 15 34 26 35 28 28
 None   470 26 35 21 37 23 40 30 28
  P d   0.05 0.25 0.01 <0.0001 <0.0001 <0.0001 0.62 0.003
BMI f           
Males           
 1st quartile   1155 29 30 17 33 33 29 30 22
 2nd quartile   1179 28 34 16 31 33 28 32 22
 3rd quartile   1159 31 30 18 34 31 29 30 24
 4th quartile   1147 29 32 16 36 28 36 31 24
  P d   0.44 0.24 0.28 0.04 0.25 0.01 0.80 0.29
Females           
 1st quartile   1185 31 32 18 26 39 23 30 23
 2nd quartile   1184 32 32 17 32 35 26 32 25
 3rd quartile   1196 32 32 18 30 32 30 29 25
 4th quartile   1177 30 32 19 34 29 30 29 28
  P d   0.71 0.95 0.25 <0.0001 0.001 0.12 0.27 0.03
  1. aN given for participants with change in activity and social class/education/BMI data. Numbers for change in chips, fried food and fruit/salad consumption varies slightly (−8 to +2).
  2. bN given for participants with change in activity and social class data. Numbers for change in activity and education or BMI varies slightly (−16 to +91).
  3. cSocial class at birth. Social class V includes those with no male head of household.
  4. dP-value for χ2-test comparing those who increased or decreased their activity/diet with those who remained stable (stable category not shown).
  5. eQualifications in 1991 (33 y).
  6. fBMI in 1991 (33 y). 1st quartile is lowest. Quartile cutoffs, males; 23.1212, 25.1205, 27.5021 kg/m2, females; 21.4421, 23.4501, 26.4453 kg/m2.