Table 2

Consumption of selected phytoestrogen-rich foods and thyroid cancer risk among women participating in the Bay Area Thyroid Cancer Study

Food (g/day)CasesControlsORa95% CIORb95% CI
Traditional soy-based foods
 Nonfermented
  Tofu
   Nonconsumers2632131.01.0
   Consumers
    0.1–4.91671450.880.65–1.20.880.64–1.2
    5.0–14.971640.800.53–1.20.840.55–1.3
    15.0–49.953670.560.36–0.870.580.36–0.91
    ≥50.036550.440.26–0.720.500.30–0.84
  Soy milk
   Nonconsumers4974491.01.0
   Consumers
    0.1–14.955391.20.77–1.91.30.79–2.1
    15.0–49.915300.420.22–0.810.450.23–0.89
    ≥50.023260.770.43–1.40.810.44–1.5
 Fermented
  Miso soup
   Nonconsumers3693321.01.0
   Consumers
    0.1–4.9111971.00.75–1.41.10.75–1.5
    5.0–9.943490.750.48–1.20.760.48–1.2
    ≥10.067660.870.59–1.30.920.62–1.4
Nontraditional soy-based foods
 Soy-burgers & meat substitutes
  Nonconsumers5004211.01.0
  Consumers
   0.1–0.940460.740.47–1.20.810.50–1.3
   1.0–3.925390.530.31–0.890.510.29–0.89
   ≥4.025380.540.32–0.920.630.37–1.1
Sprouts
 Soybean sproutsc
  Nonconsumers101741.01.0
  Consumers
   0.1–2.932280.850.47–1.50.830.45–1.6
   3.0–4.928310.660.36–1.20.800.43–1.5
   5.0–14.925220.830.43–1.60.920.47–1.8
   ≥15.024330.510.28–0.940.590.31–1.1
 Alfalfa sprouts
  Nonconsumers2932451.01.0
  Consumers
   0.01–0.251071150.800.58–1.10.760.55–1.1
   0.26–0.991331111.00.74–1.41.10.77–1.5
   ≥1.057730.640.43–0.940.620.41–0.93
Foods with added soy flour
 Doughnuts
  Nonconsumers1081081.01.0
  Consumers
   0.1–0.91331301.00.72–1.50.990.68–1.5
   1.0–1.91221141.10.72–1.51.00.71–1.6
   2.0–4.982651.20.80–1.91.30.81–2.0
   5.0–9.974830.850.56–1.30.890.57–1.4
   ≥10.071441.50.91–2.41.50.90–2.5
 White bread
  Nonconsumers1231161.01.0
  Consumers
   2.0–9.91641461.00.75–1.51.10.74–1.5
   10.0–19.992761.10.74–1.71.10.71–1.7
   20.0–29.91101100.890.61–1.30.970.65–1.4
   ≥30.0101960.930.63–1.40.920.61–1.4
 Pancakes, waffles
  Nonconsumers102961.01.0
  Consumers
   0.1–1.91411410.980.68–1.40.990.67–1.5
   2.0–3.91291141.10.73–1.61.00.70–1.6
   4.0–9.999980.940.63–1.40.980.64–1.5
   ≥10.0119951.10.75–1.71.00.68–1.6
Foods with added soy protein
 Canned tuna
  Nonconsumers1141301.01.0
  Consumers
   0.1–3.91491321.30.94–1.91.30.88–1.8
   4.0–9.92031651.41.0–2.01.51.0–2.1
   10.0–29.968591.30.86–2.11.30.82–2.1
   ≥30.056581.10.69–1.71.10.70–1.8
  • a Adjusted for age, race/ethnicity, and daily caloric intake.

  • b Adjusted for age, race/ethnicity, daily caloric intake, goiter or thyroid nodules, radiation to the head or neck, and family history of proliferative thyroid disease.

  • c Among Asian women only.