Table 2 Comparison^a of reported soy isoflavones and nutrient intake on the web-based food frequency questionnaire with the reference method (food records with digital photographs) without energy adjustment and with energy adjustment (n = 55)

Energy, MJ

8.77

6.29

7.63

2.56

0.02

Total isoflavones, mg

9.31

30.50

3.16

18.03

<0.001

9.40

29.24

2.64

13.47

<0.001

 Daidzein, mg

3.50

12.70

1.35

7.05

<0.001

3.57

11.94

1.03

5.39

<0.001

 Genistein, mg

4.98

15.37

1.68

9.37

<0.001

4.92

14.82

1.36

7.09

<0.001

 Glycitein, mg

0.82

2.96

0.27

1.50

<0.001

1.07

2.70

0.27

1.24

<0.001

Fat, g

81.33

48.36

65.19

27.63

<0.001

78.89

10.92

62.39

14.37

<0.001

 SFA, g

26.41

16.66

21.25

9.15

<0.001

26.20

8.58

19.59

7.45

<0.001

 MUFA, g

27.75

18.29

21.85

10.00

0.001

26.21

4.83

20.88

3.97

<0.001

 PUFA, g

21.50

12.93

17.05

7.06

0.001

20.01

7.28

15.79

4.65

<0.001

 Trans fats, g

2.35

1.52

2.11

1.29

0.12

2.38

0.92

2.27

1.10

0.13

Carbohydrate, g

266.33

137.70

242.66

90.64

0.46

251.84

34.06

253.35

34.48

0.16

Protein, g

80.66

57.78

62.40

28.15

<0.001

76.46

11.29

62.99

16.59

<0.001

 Animal protein, g

29.88

29.70

25.36

23.53

0.004

30.19

23.99

26.34

23.25

<0.001

 Vegetable protein, g

44.88

27.37

35.92

21.10

<0.001

44.80

19.45

35.63

12.66

<0.001

Dietary fiber, g

26.75

15.01

20.20

12.23

<0.001

25.74

9.06

20.32

7.92

<0.001

Beta carotene, mcg

4038.70

3816.72

2547.64

2502.86

0.002

3629.93

2578.13

2432.11

2355.71

0.002

Retinol, mcg

512.33

354.03

386.66

251.29

<0.001

494.90

210.82

396.22

215.04

<0.001

Vitamin E, mg

10.07

6.57

9.42

4.57

0.56

9.03

3.09

9.69

3.33

0.06

Vitamin C, mg

133.10

96.47

76.72

71.61

<0.001

130.15

87.41

75.53

69.30

<0.001

Folate, mcg

606.31

374.12

422.31

208.30

<0.001

578.85

195.57

439.31

165.14

<0.001

Vitamin B12, mcg

6.62

4.14

4.07

2.54

<0.001

6.09

2.59

3.70

2.27

<0.001

Calcium, mg

1149.29

547.37

855.00

514.07

<0.001

1125.58

400.07

839.31

382.86

<0.001

Iron, mg

17.82

8.30

14.21

6.32

<0.001

17.23

3.80

14.07

3.38

<0.001

Zinc, mg

11.72

6.41

7.81

4.97

<0.001

11.60

2.36

8.37

3.36

<0.001

Caffeine, mg

9.06

24.06

4.64

15.67

0.07

8.39

19.36

4.62

15.53

0.05