Table 1

Dietary total fiber and mean levels of biological risk markers and adjusted relative risk of type 2 diabetes by quartiles of total, cereal, and vegetable/fruit fiber intake

Quartiles of total fiber (g/day)
P for trend
1 (≤20)2 (20.1–24.9)3 (25.0–30.9)4 (31.0+)
n864854841869
Systolic blood pressure (mmHg)148.4148.0148.9148.30.96
Triglycerides (mmol/l)*1.631.581.571.570.04
HDL cholesterol (mmol/l)1.341.321.341.340.79
Glucose (mmol/l)*5.535.535.535.530.94
HOMA0.680.720.690.630.05
GGT (IU/dl)*30.628.226.025.8<0.0001
ALT (IU/dl)15.315.315.615.60.40
CRP (mg/l)*2.141.701.601.35<0.0001
IL-6 (pg/ml)*2.802.362.342.16<0.0001
t-PA (ng/ml)11.711.110.410.1<0.0001
Total fiber (quarters)Low (≤20 g/day) vs. rest
    Diabetes rate/1,000 person-years (n)9.5 (54)7.7 (41)5.4 (30)6.5 (37)
    Relative risk (95% CI)
        Age adjusted1.000.72 (0.48–1.17)0.53 (0.34–0.83)0.63 (0.42–0.96)1.60 (1.15–2.21)
        A1.000.68 (0.44–1.04)0.59 (0.37–0.95)0.82 (0.51–1.32)1.47 (1.03–2.11)
        B1.000.70 (0.45–1.07)0.61 (0.38–0.98)0.83 (0.52–1.13)1.43 (1.00–2.02)
        C1.000.70 (0.46–1.03)0.64 (0.40–0.97)0.86 (0.50–1.20)1.39 (0.97–1.99)
        D1.000.76 (0.49–1.18)0.69 (0.43–1.13)0.95 (0.59–1.53)1.28 (0.88–1.86)
Cereal fiber (quarters)Low (<6.9 g/day) vs. rest
    Diabetes rate/1,000 person-years (n)10.0 (55)6.9 (38)6.1 (35)6.1 (34)
    Relative risk (95% CI)
        Age adjusted1.000.69 (0.46–1.05)0.61 (0.40–0.94)0.56 (0.37–0.86)1.61 (1.16–2.23)
        A1.000.75 (0.48–1.17)0.64 (0.41–1.02)0.70 (0.44–1.12)1.43 (1.00–2.06)
        B1.000.76 (0.50–1.19)0.65 (0.41–1.03)0.71 (0.44–1.14)1.42 (0.98–2.04)
        C1.000.77 (0.49–1.20)0.66 (0.42–1.05)0.72 (0.45–1.16)1.39 (0.97–2.04)
        D1.000.79 (0.51–1.24)0.71 (0.45–1.13)0.76 (0.47–1.22)1.32 (0.91–1.91)
Vegetable fiber (quarters)Low (<11.3 g/day) vs. rest
    Diabetes rate/1,000 person-years (n)10.3 (61)7.2 (42)5.7 (32)5.9 (34)
    Relative risk (95% CI)
        Age adjusted1.000.71 (0.47–1.06)0.55 (0.36–0.85)0.57 (0.37–0.88)1.64 (1.18–2.29)
        A1.000.83 (0.55–1.27)0.59 (0.37–0.93)0.74 (0.46–1.19)1.40 (0.98–1.98)
        B1.000.84 (0.55–1.29)0.60 (0.38–0.94)0.76 (0.49–1.22)1.38 (0.97–1.95)
        C1.000.87 (0.57–1.32)0.60 (0.38–0.95)0.75 (0.51–1.21)1.36 (0.96–1.94)
        D1.000.93 (0.61–1.42)0.63 (0.39–0.99)0.83 (0.50–1.31)1.28 (0.89–1.82)
  • Data are means or *geometric means, as shown, unless otherwise indicated. A, adjusted for age, waist circumference, cigarette smoking, physical activity, social class, alcohol intake, preexisting myocardial infarction, stroke, use of statins, and total calorie intake; B, adjusted for A and IL-6; C, adjusted for A and IL-6 and t-PA; D, adjusted for A and IL-6, t-PA antigen, and GGT. Low = bottom quartile of the fiber distribution, rest = 2nd–4th quartile.