Table 1 Characteristics and dietary intakes across tertiles of dietary protein among the study participants

Demographic variables

  Age(year)

37.6 ± 8.5

38.4 ± 8.7

38.5 ± 9.4

0.258

  Male, n (%)

120 (51.7)

131 (58.2)

107 (49.1)

0.137

  BMI(Kg/m²)

26.9 ± 4.5

26.5 ± 4.0

27.2 ± 4.5

0.444

  Smoking, n (%)

7 (3)

11 (4.9)

10 (4.6)

0.544

  Physical activity (MET/min/week)

1424 ± 916

1496 ± 909

1377 ± 809

0.553

  SES, n (%)

0.530

    Low

80 (34.5)

64 (28.4)

79 (36.2)

    Middle

103 (44.4)

108 (48)

99 (45.4)

    High

49 (21.1)

53 (23.6)

40 (18.3)

Nutrient intake

  Energy intake (Kcal/d)

2333 ± 655

2281 ± 642

2206 ± 619

0.035

  Carbohydrate (% of energy)

57.8 ± 8.4

58.4 ± 6.4

55.8 ± 6.3

0.003

  fat (% of energy)

33.3 ± 8.3

30.6 ± 6.3

30.8 ± 5.6

 < 0.001

  Saturated fats(% of energy)

10.1 ± 3.3

10.4 ± 2.8

10.6 ± 2.8

0.068

  Polyunsaturated fatty acids(% of energy)

7.6 ± 2.8

6.0 ± 1.7

5.7 ± 1.6

 < 0.001

  Fibre (g/1000 kcal)

16.4 ± 8.5

16.8 ± 7.3

15.3 ± 5.2

0.014

  BCAAs (% of energy)

1.99 ± 0.31

2.41 ± 0.32

2.83 ± 0.47

 < 0.001

  AAAs (% of energy)

1.03 ± 0.15

1.24 ± 0.15

1.45 ± 0.23

 < 0.001

  SAAs (% of energy)

0.41 ± 0.06

0.48 ± 0.06

0.57 ± 0.10

 < 0.001