Table 1.
Main characteristics of cohort/case–control studies in the meta-analysis.
| First Author, Year |
Country (Study Name) |
Study Design (Study Period) |
Age (Years) |
Cases/ Sample |
Exposure Category (Lowest vs. Highest) |
Cancer Type |
|---|---|---|---|---|---|---|
| Chyou, 1995 [76] | USA | Cohort (1965–1993) |
45–68 | 92/7994 | Miso soup, tofu <1 times/week (ref) ≥5 times/week |
Upper aerodigestive tract |
| Galanis, 1998 [34] | USA | Cohort (1975–1994) |
46.4 ± 16.6 | 108/11,907 | Miso soup None (ref), 1 or more times/week |
Gastric |
| Nomura, 2004 [77] | USA | Cohort (1971–1995) |
NA | 304/5826 | Tofu 0 g/week (ref), >240 g/week |
Prostate |
| Oba, 2007 [40] | Japan (Takayama Study) |
Cohort (1993–2000) |
>35 | 210/30,221 | Soy product 49.2 g/day (ref), 141.1 g/day (M) 46.3 g/day (ref), 128.0 g/day (F) |
Colon |
| Akhter, 2008 [35] | Japan (Japan Public Health Center-Based Prospective Study) |
Cohort (1995–2004) |
45–74 | 886/83,063 | Soy food 35.4 g/day (ref), 169.9 g/day (M) 35.6 g/day (ref), 170.3 g/day (F) Miso soup 147.5 mL/day (ref) 313.7 mL/day (M) 125.6 mL/day (ref) 261.3 mL/day (F) |
Colorectal |
| Seow, 2009 [78] | Singapore (Singapore Chinese Health Study) |
Cohort (1993–2005) |
45–74 | 298/34,028 | Soybean drink 30.7 g/day (ref), 197.7 g/day |
Lung |
| Wang, 2009 [79] | USA (The Women’s Health Study) |
Cohort (1992–2007) |
≥45 | 3196/37,938 | Tofu <1 serving/month (ref) ≥2 servings/week |
Total |
| Yang, 2009 [80] | China (Shanghai Women’s Health Study) |
Cohort (1997–2005) |
51.6 ± 9 | 321/68,412 | Soy foods ≤12.8 g/day (ref), >21 g/day |
Colorectal |
| Hara, 2012 [36] | Japan (Japan Public Health Center-Based Prospective Study) |
Cohort (1995–2006) |
45–74 | 1249/84,881 | Miso soup 63 mL/day (ref), 449 mL/day (M) 47 mL/day (ref), 384 mL/day (F) Soy food 33.4 g/day (ref), 140.6 g/day (M) 33.6 g/day (ref), 141 g/day (F) |
Gastric |
| Ollberding, 2012 [81] | USA (Multiethnic Postmenopausal Women’s Cohort Study) |
Cohort (1993–2007) |
61.6 ± 7.7 | 489/46,027 | Tofu 0–0.21 g/1000 kcal/day (ref) ≥7.56 g/1000 kcal/day |
Endometrial |
| Ko, 2013 [47] | Korea (Korean Hereditary Breast Cancer Study) |
Cohort (2007–2011) |
≥20 | 2002/2271 | Soybean products 0–1 times/week (ref) 4–5 times/week |
Breast |
| Wada, 2015 [19] | Japan (Takayama Study) |
Cohort (1992–2008) |
>35 | 678/30,792 | Soy foods 38.4 g/day (ref), 176.3 g/day (M) 43.5 g/day (ref), 168.7 g/day (F) Fermented soy foods 6.6 g/day (ref), 37.3 g/day (M) 7.5 g/day (ref), 34.0 g/day (F) Non-fermented 27.7 g/day (ref), 147.8 g/day (M) 32.0 g/day (ref), 140.8 g/day (F) |
Stomach |
| Paul, 2019 [82] | Singapore (Singapore Chinese Health Study) |
Cohort (1993–2013) |
45–74 | 312/30,744 | Soy food 31.29 g/1000 kcal/day 115.86 g/1000 kcal/day |
Cervical |
| Abe, 2020 [20] | Japan (Japan Public Health Center-Based Prospective Study) |
Cohort (1995–2013) |
40–69 | 534/75,089 | Miso, natto, tofu, fermented Non-fermented, total soy food Quartile 1 (ref), quartile 4 Soymilk Non-consumer (ref), consumer |
Liver |
| Shirabe, 2021 [83] | Japan (Japan Public Health Center-Based Prospective Study) |
Cohort (1995–2013) |
45–74 | 825/47,614 | Total soy foods 31.8 g/day (ref), 137 g/day Fermented soy foods 7.3 g/day (ref), 53.2 g/day Miso 2.9 g/day (ref), 29.1 g/day Natto 0.01 g/day (ref), 32.7 g/day Non-fermented soy foods 13.5 g/day (ref), 98.5 g/day Tofu 10.3 g/day (ref), 74.1 g/day Soy milk No (ref), Yes |
Breast |
| Nozue, 2021 [37] | Japan (Japan Public Health Center-based Prospective Study) |
Cohort (1995–2012) |
40–69 | 9972/79,648 | Total soy product 33.6 g/day (ref), 140.9 g/day (W) 33.7 g/day (ref), 130.9 g/day (M) Fermented soy products 8.6 g/day (ref), 55.1 g/day (W) 9.5 g/day (ref), 60 g/day (M) Non-fermented soy products 13.5 g/day (ref), 99.5 g/day (W) 12.1 g/day (ref), 97 g/day (M) Miso 3.8 g/day (ref), 30.5 g/day (W) 5.1 g/day (ref), 35.8 g/day (M) Natto 0 g/day (ref), 32.4 g/day (W) 0 g/day (ref), 32.1 g/day (M) |
Total |
| Shin, 2023 [17] | Korea (the Health Examinees study) |
Cohort (2004–2013) |
40–69 | 767/109,161 | Soybean paste, tofu Almost never (ref) ≥2 times/week |
Gastric |
| Lee, 1995 [12] | Korea | Case–control (1990–1991) |
>25 | 213/425 | Tofu None or 4–5 times/year (ref) ≥2–3 times/week |
Stomach |
| Horn-Ross, 2001 [56] | USA (Multiethnic Bay Area Breast Cancer Study) |
Case–control (1995–1998) |
35–79 | 1314/2917 | Tofu, miso soup Non-consumers (ref) ≥1 times/month Soy milk Non-consumers (ref), consumers |
Breast |
| Seow, 2002 [45] | Singapore (Singapore Chinese Women’s health study) |
Case–control (1996–1998) |
20–89 | 303/1064 | Soy foods <2.2 servings/week (ref) ≥5.4 servings/week |
Lung |
| Wu, 2002 [57] | USA | Case–control (1995–1998) |
25–74 | 494/1086 | Tofu Less than monthly (ref) >4 times/week |
Breast |
| Hirose, 2003 [44] | Japan (Aichi Cancer Center-Based Women’s Health Study) |
Case–control (1988–2000) |
>30 | 2382/21,377 | Soybean curd <1–3 times/month ≥5 times/week Miso soup Almost never (ref), 2 times/day |
Breast |
| Lee, 2003 [13] | Korea | Case–control (1999) |
>18 | 69/268 | Soybean curd <1 times/week (ref) ≥1 times/month |
Gastric |
| Jian, 2004 [58] | China | Case–control (2001–2002) |
>45 | 130/404 | Fermented soy products 0 g/day (ref), >4 g/day |
Prostate |
| Hung, 2004 [42] | China | Case–control (1996–2002) |
Case (41–93) Control (41–89) |
522/1428 | Fermented bean product <1 (ref), ≥1 times/week |
Esophageal |
| Machida-montani, 2004 [59] | Japan | Case–control (1998–2002) |
20–74 | 122/357 | Miso soup <3 (ref), ≥4 cups/day |
Gastric |
| Sonoda, 2004 [60] | Japan | Case–control (1996–2002) |
59–73 | 140/280 | Tofu ≤19.7 g/day (ref), ≥96.4 g/day All soy products ≤77 g/day (ref), ≥187.2 g/day Natto ≤5.7 g/day (ref), ≥40 g/d |
Prostate |
| Xu, 2004 [61] | China (Shanghai Women’s Population-Based Case–control Study) |
Case–control (1997–2001) |
30–69 | 832/1678 | Soy milk Never (ref), >1.9 g/day Tofu ≤0.8 (ref), >3.5 g/day Soya products (no tofu) ≤1.8 (ref), >8.8 g/day |
Endometrial |
| Nan, 2005 [5] | Korea | Case–control (1997–2003) |
Case 60 ± 11 Control 59 ± 10 |
421/1053 | Soybean paste Low (ref), high |
Gastric |
| Hirose, 2005 [14] | Japan (Aichi Cancer Center-Based Women’s Health Study) |
Case–control (2001–2002) |
>30 | 167/1021 | Soybean products, tofu, Miso, natto Tertile 1 (ref), Tertile 3 |
Breast |
| Sharp, 2005 [62] | Japan (A-bomb Survivors Cohort-Based, Case–control Study) |
Case–control (1965–1988) |
NA | 102/339 | Miso soup, tofu Never or ≤1/week (ref) ≥5 times/week |
Hepatocellular |
| Shannon, 2005 [63] | China (Shanghai Women’s Study) |
Case–control (1995–2000) |
>35 | 378/1448 | Total soy food ≤2.6 servings/week (ref) ≥1.1 servings/day Unfermented soy food ≤2.3 servings/week (ref) ≥1 servings/day |
Breast |
| Heald, 2007 [64] | Scottish (Prostate Cancer And Diet Study) |
Case–control (1998–2001) |
50–74 | 433/916 | Soy food consumption No (ref), Yes |
Prostate |
| Kim, 2008 [65] | Korea | Case–control (2004–2006) |
Case 46.1 ± 8.5 Control 46 ± 8.6 |
362/724 | Tofu <7.73 g/day (ref), ≥49.5 g/day |
Breast |
| Li, 2008 [66] | China (Changchun Mass Screening-Based Case–control study) |
Case–control (1998–2000) |
>50 | 28/308 | Soybean food (tofu and foymilk) ≤2 times/day (ref) ≥1 times/day |
Prostate |
| Matsuo, 2008 [16] | Japan (Aichi Cancer Center Hospital-Based Case–control Study) |
Case–control (2001–2005) |
18–79 | 353/2110 | Soybean products 19.8 (ref), 81.8 g/day Miso soup ≤3–4 times/week (ref) twice a day Tofu ≤1–3 times/month (ref) ≥3–4 times/week Natto ≤1–3 times/month (ref) ≥ once a day |
Lung |
| Bandera, 2009 [67] | USA (Estrogen, Diet, Genetics and Endometrial Cancer Study) |
Case–control (2001–2003) |
>21 | 408/797 | Tofu, soy milk, miso Never (ref), Ever |
Endometrial |
| Liu, 2009 [68] | China | Case–control (1997–2005) |
2–20 | 195/683 | Bean curd foods Rare or occasional (ref), frequent |
Leukemia |
| Hosono, 2010 [46] | Japan | Case–control (2001–2005) |
NA | 405/2430 | Tofu None (ref), >5 times/week |
Cervical |
| Budhathoki, 2011 [41] | Japan (The Fukuoka Colorectal Cancer Study) |
Case–control (2000–2003) |
Case 60.5 ± 9.1 Control 58.9 ± 10.7 |
816/1631 | Soy foods 5.4 g/day (ref), 26.8 g/day |
Colorectal |
| Chihara, 2012 [38] | Japan | Case–control (2001–2005) |
18–80 | 295/1765 | Miso soup, tofu, natto <1 times/day (ref), ≥1 times/day |
Non-Hodgkin lymphoma |
| Wang, 2012 [69] | China (Northwest China’s Hospital-Based Case–control Study) |
Case–control (2009–2011) |
NA | 220/440 | Soy food Never (ref), ≥3 times/week |
Multiple myeloma |
| Wang, 2012 [70] | China (XiAn’s Population- Based Case–control Study) |
Case–control (2008–2010) |
30–79 | 257/771 | Soya products Tertile 1 (ref), Tertile 3 |
Gastric |
| Zaineddin, 2012 [71] | Germany (German Case–control Study) |
Case–control (2005–2006) |
50–74 | 3157/9211 | Soy milk, tofu, paste No consumption (ref) High consumption |
Breast |
| Lee, 2014 [72] | China (Guangdong Hospital-Based 1:1 Case–control Study) |
Case–control (2006–2008) |
Average 75 |
500/1000 | Total soy foods ≤61.4 g/day (ref), >119 g/day Soy milk ≤12.9 mL/day (ref), >38.6 mL/day Tofu ≤8.6 g/day (ref), >20 g/day |
Ovarian |
| Tang, 2015 [73] | China (Xinjiang Hospital-Based Case–control Study) |
Case–control (2008–2009) |
Average 61 |
359/539 | Total soya foods <26 g/day (ref), >97 g/day Soya milk <2 mL/day (ref), >60 mL/day |
Esophageal |
| Shin, 2015 [15] | Korea | Case–control (2010–2013) |
NA | 962/3727 | Soy products <40.34 g/day (ref) ≥105.03 g/day (M) <42.77 g/day (ref) ≥113.66 g/day (F) Tofu <17.19 g/day (ref) ≥52.86 g/day (M) <18.73 g/day (ref) ≥54.91 g/day (F) Soymilk 0 g/day (ref), ≥21.35 g/day (M) 0 g/day (ref), ≥19.1 g/day (F) Fermented soy paste <1.95 g/day (ref) ≥8.32 g/day (M) <2.08 g/day (ref) ≥8.7 g/day (F) |
Colorectal |
| Yang, 2017 [18] | Korea (National Cancer Center Gastric Cancer Research) |
Case–control (2011–2014) |
Case 53.9 ± 9.19 Control 53.8 ± 9.05 |
377/1131 | Total soy products ≤48.39 g/day (ref), >86.2 g/day Fermented soy foods ≤2.29 g/day (ref), >5.78 g/day Non-fermented soy foods ≤42.95 g/day (ref), >85.54 g/day Tofu ≤20.47 g/day (ref), >40.05 g/day Soymilk ≤4.24 × 10−9 g/day (ref), ≥3.55 g/day |
Gastric |
| Barrett, 2019 [43] | China (NPC Genes, Environment, and EBV Study) |
Case–control (2010–2013) |
20–74 | 4806/9614 | Fermented bean curds (adult) 0 g/day (ref), ≥0.66 g/day (M) 0 g/day (ref), >0.33 g/day (W) Bean paste (adult) 0 g/day (ref), ≥1.66 g/day Fermented bean curds (adolescent) 0 g/day (ref), ≥0.66 g/day (M) 0 g/day (ref), >0.54 g/day (W) Bean paste (adolescent) 0 g/day (ref), >2.5 g/day |
Nasopharyngeal carcinoma |
| Cao, 2022 [74] | China (Chinese Wuxi Exposure and Breast Cancer Study) |
Case–control (2013–2014) |
>18 | 818/1753 | Soy foods 0–3.3 g/day (ref), ≥57.1 g/day |
Breast |
| Teng, 2023 [39] | China | Case–control (2018–2019) |
25–80 | 113/405 | Soybean products 0–10 g/day (ref) 41.8–181.7 g/day |
Bladder |
| Kwak, 2023 [75] | Korea | Case–control (2002–2006) |
20–70 | 82/164 | Soy products Tertile 1 (ref), Tertile 3 |
Gastric |
M: male; F: female; NA: not available; ref: reference.