Table 1.

Characteristics of the population in the cohort studies

Exposure
Author (ref), country, studyCohort/cases (cancer type)Sex/ageFollow-upAssessmentVariableValue ♀Value ♂
Cross and colleagues (35),a USA, NIH-AARP Diet and Health Study300,948/2,719 (colorectal)♀♂/50–71 y7.2124 item FFQbHeme iron (μg/1,000 kcal)150.3c
Dietary iron (mg/1,000 kcal)8.2c
Total iron (mg/d)21.5c
Zhang and colleagues (36), USA, NHS and HPFUS115,061/2,114 (colorectal)♀♂/NHS 30–55 y2261–130 item FFQHeme iron (mg/d)1.1c1.2c
and HPFUS 40–75 y
Balder and colleagues (37), Netherlands, Netherlands Cohort Study120,852/1,535 (colorectal)♀♂/55–69 y9.3150-item FFQHeme iron (mg/d)0.92c1.08c
Dietary iron (mg/d)11c13c
Hara and colleagues (38), Japan, Japan PH Center-based Prospective Study85,097/1,284 (colorectal)♀♂/45–74 y5138-item FFQbHeme iron (mg/d)0.44d0.61d
Lee DH and colleagues (39), USA, Iowa Women's Health Study34,708♀/55–69 y15127-item FFQHeme iron (mg/d) proximal and distal1.16–1.64e
438 proximal + 303 distal (colon)
Kabat GC and colleagues (40), Canada49,654/617 (colorectal)♀/40–59 y16.486-item FFQHeme iron (mg/d)1.99–2.40e
Dietary iron (mg/d)12.90–13.82e
Larsson and colleagues (41), Sweden, Swedish Mammography Cohort61,433/547 (colon)♀/40–75 y14.8FFQHeme iron (mg/d)1.04–1.52e
Ekblom and colleagues (42), Sweden, Northern Sweden Health and Disease StudyNA/226 (colorectal)♀♂/50.3–60.25NADietary NAPlasma ferritin (μg/L)60.8–180.3f
Blood samplePlasma transferrin saturation (%)28.7–46.8f
Plasma TIBC (μmol/L)48.1–57.3f
Plasma iron (μmol/L)15.1–23.2f
Cross and colleagues (43), Finland, Alfa-tocopherol, Beta-carotene cáncer prevention study29,133♂/50–69 y14.2276-item FFQDietary iron (mg/d)19c
130 cases: 73 (colon) + 57 (rectal) (colorectal)Blood sampleSerum iron (μg/dL)124c
Serum ferritin (ng/mL)141c
Transferrin saturation (%)38c
TIBC (μg/dL)326c
Kato and colleagues (25), USA, New York University Women's Health Study cohort15,785/105 (colorectal)♀/34–65 y4.7FFQTotal iron (mg/d)13.7d
Blood sampleSerum iron (μg/dL)83d
TIBC (μg/dL)325.2d
Transferrin saturation (%)25.8d
Serum ferritin (ng/mL)88.4d
Wurzelmann and colleagues (44), USA, National Health and Nutrition Examination Survey I and National Health Evaluation Follow-up study11,317/156 (colorectal)♀♂/31–74 y15FFQ + 24h-RDietary iron (mg/d)9.6d13.5d
Serum iron (μg/dL)96.7d106.1d
Jakzsyn and colleagues (59), Europe, European Prospective Study into Cancer and Nutrition481,419/444 (gastric)♀♂/35–70 y8.788–266 item FFQHeme iron (mg/d)1.02g
Cook and colleagues (60), Finland, Alfa-tocopherol, Beta-carotene cáncer prevention study29,133/341 (gastric)♂/50–69 y22276-item FFQDietary iron (mg/d)18d
Total iron (mg/d)22d
Blood sampleSerum iron (μg/dL)117d
Serum ferritin (ng/mL)156d
Transferrin saturation (%)36d
TIBC (μg/dL)329d
Cross and colleagues (58)a, USA, National Institutes of Health - AARP Diet and Health study303,156/505 (esophageal)♀♂/50–71 y10124-item FFQbHeme iron (μg/1,000 kcal)154.2c
532 (gastric)
Steffen and colleagues (68), Europe, European Prospective Study into Cancer and Nutrition348,738/151 (esophageal)g♀♂/35–70 y11.8FFQbHeme iron (μg/1,000 kcal)245c
Kabat and colleagues (50)a, USA, NIH-AARP Diet and Health Study116,674/3,396 (breast)♀/50–71 y6.5124-item FFQb + FFQ with meat-cooking moduleDietary iron (mg/d)8.2c
Heme iron (mg/d)124.6c
Kabat GC and colleagues (51), Canada, Canadian National Breast Screening Study49,654/2,545 (breast)♀/40–59 y16.486-item FFQDietary iron (mg/d)12.90–13.82e
Heme iron (mg/d)1.99–2.40e
Ferrucci and colleagues (52)a, USA, PLCO Cancer Screening Trial52,158/1,205 (breast)♀/55–74 y5.5124-item FFQDietary iron (mg/1,000 kcal)8.3c
Heme iron from meat (mg/1,000 kcal)0.14c
Tasevska and colleagues (69)a, USA, NIH-AARP Diet and Health Study46,7976/6,361 (lung)♀♂/50–71 y8124-item FFQb + FFQ with meat-cooking moduleHeme iron (μg/1,000 kcal)125.2c171.1c
Tasevska and colleagues (70)a, USA, PLCO Cancer Screening Trial99,579/782 (lung)♀♂/55–74 y8124-item FFQb + DHQc + meat-cooking moduleHeme iron (μg/1,000 kcal)136c191c
Lee DH and colleagues (71), USA, Iowa Women's Health Study34,708/700 (lung)♀/55–69 y16127-item FFQHeme iron (mg/d)1.65c
Genkinger and colleagues (81), Sweden, Swedish Mammography Cohort60,895/720 (endometrial)♀/40–76 y2167-item FFQ + 96-item FFQbHeme iron (mg/d)1.13c
Dietary iron (mg/d)13.62c
Kabat and colleagues (82), Canada, Canadian National Breast Screening Study34,148/426 (endometrial)♀/40–59 y16.486-item FFQDietary iron (mg/d)12.90–13.82e
Heme iron (mg/d)1.99–2.40e
Jakzsyn and colleagues (83), Europe, European Prospective Study into Cancer and Nutrition481,419/1,001 (bladder)♀♂/35–70 y8.7FFQHeme iron (mg/d)1.02c
Molina-Montes and colleagues (84), Europe, European Prospective Study into Cancer and Nutrition477,202/865 (pancreatic)♀♂/25–70 y11.3FFQbDietary iron (mg/d)11.9c14.3c
Heme iron (mg/d)0.9c1.4c
Jakzsyn and colleagues (85), Europe, European Prospective Study into Cancer and Nutrition139,005/4,606 (prostate)♂/35–70 y11FFQHeme iron (mg/d)1.45c

Abbreviation: NA, not available.

  • aHeme iron estimation according to NCI database (only meat food sources).

  • bFFQ validated with 14-, 28-, or 1-week dietary records.

  • cMedian.

  • dMean.

  • ePercentile 40 and 60.

  • f25th–75th percentile.

  • gOnly squamous cell carcinoma.