Table 4.

Associations between diet and physical activity and BMI in pre-pregnant women (N = 755).

	Unadjusted Model		Adjusted Model
	β (95% CI)	p Value	β (95% CI)	p Value
Age, year	0.20 (0.14, 0.25)	<0.001	0.22 (0.15, 0.29)	<0.001
Country of birth
Australia (ref.)
Other English-speaking country	−0.20 (−2.05, 1.66)	0.832	0.34 (−1.10, 1.79)	0.639
Others	−3.04 (−4.11, −1.96)	<0.001	−3.20 (−4.52, −1.88)	<0.001
Remoteness area
Major cities (ref.)
Inner regional	1.77 (0.22, 3.32)	0.026	0.36 (−1.04, 1.76)	0.613
Other	3.01 (0.83, 5.20)	0.008	1.73 (−0.37, 3.83)	0.104
Marital status
Not married (ref.)
Married	0.30 (−0.95, 1.55)	0.633	−0.51 (−1.79, 0.77)	0.432
Education
Bachelor/Graduate diploma (ref.)
Certificates/Advanced diploma	0.99 (−0.42, 2.41)	0.164	−0.97 (−2.62, 0.67)	0.242
No non-school qualification	2.09 (0.34, 3.85)	0.020	−0.56 (−2.18,1.06)	0.491
Household income (cont. decile)	−0.08 (−0.33, 0.18)	0.553	··	··
Occupation
Clerical trade (ref.)
Professional	−0.82 (−2.54, 0.91)	0.347	−0.77 (−2.33, 0.79)	0.327
Assoc. Professional	−0.90 (−2.50, 0.70)	0.265	−1.08 (−2.55, 0.40)	0.150
Other	0.05 (−2.18, 2.27)	0.967	−0.54 (−2.50, 1.42)	0.584
SEIFA
1st (highest disadvantage) (ref.)
2nd quintile	−0.52 (−2.36,1.32)	0.575	−0.65 (−2.65, 1.36)	0.521
3rd quintile	−2.10 (−3.98, −0.22)	0.029	−1.16 (−2.90, 0.57)	0.184
4th quintile	−1.55 (−3.79,0.69)	0.171	−1.48 (−3.53, 0.57)	0.15
5th quintile (least disadvantage)	−2.18 (−3.98, −0.38)	0.018	−1.85 (−3.71, 0.01)	0.051
Smoking status
Never smoked (ref.)
Current smoker	0.55 (−1.09, 2.18)	0.505	−1.40 (−2.76, −0.04)	0.044
Ex-smoker	1.73 (0.05, 3.41)	0.043	0.53 (−1.08, 2.15)	0.512
Self-assessed health
Fair/poor (ref.)
Excellent/very good/good	−2.77 (−5.57, 0.03)	0.052	−2.89 (−5.51, −0.28)	0.030
Dieting
Not currently on diet (ref)
Currently on diet	2.41 (0.21, 4.61)	0.032	2.25 (0.25, 4.24)	0.028
Vegetables, legumes/beans (categorical)
<1 serves/day (ref.)
≥1 to <3 serves/day	−0.43 (−1.82, 0.96)	0.537	··	··
≥3 to <5 serves/day	0.49 (−1.24, 2.21)	0.574	··	··
≥5 serves/day	−1.56 (−3.32, 0.21)	0.083	··	··
Vegetables, legumes/beans (binary)
<5 serves/day (ref.)
≥5 serves/day	−1.48 (−2.93, −0.03)	0.046	−1.06 (−2.54, 0.42)	0.156
Fruit (categorical)
<1 serves/day (ref.)
≥1 to <2 serves/day	−1.55 (−3.86, 0.72)	0.007	··	··
≥2 to <3 serves/day	−0.79 (−2.50, 0.93)	0.363	··	··
≥3 serves/day	−1.13 (−3.19, 0.94)	0.279	··	··
Fruit (binary)
<2 serves/day (ref.)
≥2 serves/day	−0.47 (−1.84, 0.90)	0.494	0.39 (−1.04, 1.81)	0.588
Grain (cereal) foods (categorical)
Zero or none (ref.)
>0 to <2 serves/day	−1.62 (−4.71, 1.47)	0.299	··	··
≥2 to <4 serves/day	−2.48 (−5.67, 0.71)	0.125	··	··
≥4 to <6 serves/day	−2.42 (−5.73, 0.89)	0.149	··	··
≥6 serves/day	−2.78 (−6.09, 0.53)	0.098	··	··
Grain (cereal) foods (binary)
<6 serves/day (ref.)
≥6 serves/day	−0.64 (−2.07, 0.79)	0.373	0.74 (−0.92, 2.39)	0.376
Whole grain (categorical)
<1 serves/day (ref.)
≥1 to <2 serves/day	−0.64 (−2.34, 1.07)	0.459	−0.12 (−1.69, 1.44)	0.874
≥2 to <3 serves/day	−1.88 (3.43, −0.33)	0.019	−1.63 (−3.44, 0.17)	0.075
≥3 serves/day	−2.10 (−3.78, −0.41)	0.016	−1.58 (−2.96, −0.21)	0.025
Whole grains (binary)
<48 g/day (ref.)
≥48 g/day	−1.65 (−2.96, −0.34)	0.014	··	··
Whole grain (half of total grain intake)
<50% (ref.)
≥50%	−1.84 (−3.12, −0.56)	0.006	··	··
Milk and/or alternatives (categorical)
<0.5 serves/day (ref.)
≥0.5 to <1.5 serves/day	−1.23 (−3.19, 0.73)	0.214	··	··
≥1.5 to <2.5 serves/day	−1.08 (−3.05, 0.89)	0.280	··	··
≥2.5 serves/day	−1.66 (−4.22, 0.89)	0.199	··	··
Milk and/or alternatives (binary)
<2.5 serves/day (ref.)
≥2.5 serves/day	−0.86 (−2.89, 1.17)	0.401	··	··
Meats and/or alternatives (categorical)
<0.5 serves/day (ref.)
≥0.5 to <1.5 serves/day	−1.86 (−3.54, −0.17)	0.032	··	··
≥1.5 to <2.5 serves/day	−0.38 (−1.93, 1.17)	0.624	··	··
≥2.5 serves/day	−0.58 (−2.32. 1.17)	0.510	··	··
Meats and/or alternatives (binary)
<2.5 serves/day (ref.)
≥2.5 serves/day	0.22 (−1.12, 1.55)	0.748	0.87 (−0.34, 2.08)	0.157
Fibre (g/day)	−0.07 (−0.11, −0.03)	0.001	··	··
CHO (%E)	0.01 (−0.04, 0.07)	0.639	··	··
Protein (%E)	0.11 (0.03, 0.20)	0.010	··	··
Total fat (%E)	−0.03 (−0.07, 0.02)	0.197	−0.06 (−0.14, 0.03)	0.179
Trans-fat (%E)	0.84 (−0.66, 2.34)	0.268	··	··
Saturated and trans-fat (%E)	−0.05 (−0.17, 0.07)	0.414	··	··
Monosaturated fat (%E)	−0.04 (−0.18, 0.10)	0.545	··	··
Polyunsaturated fat (%E)	−0.14 (−0.47, 0.18)	0.381	··	··
Alcohol (%E)	−0.03 (0.09, 0.03)	0.352	−0.08 (−0.14, −0.005)	0.035
DF (%E)	0.02 (−0.01, 0.05)	0.221	0.01 (−0.03,0.05)	0.475
SSBs (%E)	0.09 (−0.007,0.18)	0.069	0.04 (−0.06, 0.15)	0.378
Added sugar intake (%E)	0.05 (−0.03, 0.13)	0.211	··	··
Total energy (MJ)	−0.24 (−0.42, −0.05)	0.013	−0.16 (−0.37, 0.05)	0.135
Total PA (minutes/wk) cont 1	−0.003 (−0.004, −0.001)	0.005	−0.002 (−0.004, 0.0002)	0.080
Total PA (minutes/wk) 1
Did not meet recommended guideline (ref.)
Met recommended guidelines	−1.38 (−2.86, 0.09)	0.066	··	··

Data were analysed using linear regression with data presented from univariable and multivariable linear regression analyses. Collinear diet variables (VIF > 10) were excluded (protein correlated with meat and alternatives, carbohydrate with alcohol, monosaturated fat, polyunsaturated fat, trans-fat saturated fat + trans-fat correlated with total fat, added sugar correlated with SSBs). β, beta-coefficient; CHO, carbohydrate; DF, discretionary foods; MJ, megajoules; MVPA, moderate–vigorous physical activity; PA, physical activity; SEIFA, socio-economic index of disadvantage for areas; SSBs, sugar sweetened beverage, %E, percentage energy. ¹ Total minutes of physical activity undertaken in last week (includes walking for transport + walking for fitness + Moderate + Vigorous time but does not include sessions). Used as continuous and dichotomized as whether physical activity last week met 150 min recommended guidelines.