High soy consumption significantly increases the risk of prostate cancer

This study was published in the British Journal of Cancer 2004 May 4;90(9):1792-5

Study title and authors:
Do preserved foods increase prostate cancer risk?

Jian L, Zhang DH, Lee AH, Binns CW.
School of Public Health, Curtin University of Technology, GPO Box U1987, Perth, WA 6845, Australia.

This study can be accessed at: http://www.ncbi.nlm.nih.gov/pubmed/15208621?dopt=Abstract

The study investigated the association between food and prostate cancer risk. The study included 130 patients with prostate cancer and 274 controls without cancer.

The study found:
(a) Those who consumed over four grams a day of fermented soy had a 102% increased risk of prostate cancer compared to those that did not consume any fermented soy.
(b) Those who had prostate cancer consumed 4% less fresh meat than than who did not have cancer.

The data from the study reveals that the consumption of fermented soy products was associated with a significant increase in prostate cancer risk.

Bread, cereals and soy increase the risk of ovarian cancer

This study was published in Cancer Epidemiology, Biomarkers and Prevention 2011 Feb;20(2):308-17

Study title and authors:
Dietary phytoestrogens and the risk of ovarian cancer in the women's lifestyle and health cohort study.

Hedelin M, Löf M, Andersson TM, Adlercreutz H, Weiderpass E.
Department of Genetic Research, Folkhälsan Research Center, Biomedicum Helsinki, Helsinki, Finland.

This study can be accessed at: http://www.ncbi.nlm.nih.gov/pubmed/21098648

This study investigated the relationship between diet and ovarian cancer. The study included 47,140 women who were followed for 16 years.

The study found:
(a) Women who consumed the most whole-grain bread had a 48% increased risk of ovarian cancer compared to the women who consumed the least whole-grain bread.
(b) Women who consumed the most isoflavones (soy products) had a 15% increased risk of ovarian cancer compared to the women who consumed the least isoflavones.
(c) Women who consumed the most cereal fibre had a 19% increased risk of ovarian cancer compared to the women who consumed the least cereal fibre.
(d) Women who had ovarian cancer consumed 8% less meat than women without ovarian cancer.

The data from the study shows that the risk of ovarian cancer increases with higher consumption of bread, cereals and soy.

Breast cancer rates increase with higher soy consumption

This study was published in Cancer Epidemiology, Biomarkers and Prevention 2005 Apr;14(4):805-8

 

Study title and authors:

Flavonoids and breast cancer risk in Italy.

Bosetti C, Spertini L, Parpinel M, Gnagnarella P, Lagiou P, Negri E, Franceschi S, Montella M, Peterson J, Dwyer J, Giacosa A, La Vecchia C.

Istituto di Ricerche Farmacologiche Mario Negri, Via Eritrea 62-20157 Milan, Italy. bosetti@marionegri.it

 

This study can be accessed at: http://www.ncbi.nlm.nih.gov/pubmed/15824147

This study investigated the relationship between flavonoids and breast cancer risk. The study included 2,569 women with breast cancer, and 2,588 controls.

Regarding isoflavone consumption, (from soy products), the study found that the women who ate the most isoflavones had a 5% increased risk of breast cancer compared to the women who ate the least isoflavones. 

Increased risk of breast cancer with high levels of soy consumption

This study was published in Cancer Epidemiology, Biomarkers and Prevention 2004 May;13(5):698-708

Study title and authors:
Phytoestrogen concentrations in serum and spot urine as biomarkers for dietary phytoestrogen intake and their relation to breast cancer risk in European prospective investigation of cancer and nutrition-norfolk.

Grace PB, Taylor JI, Low YL, Luben RN, Mulligan AA, Botting NP, Dowsett M, Welch AA, Khaw KT, Wareham NJ, Day NE, Bingham SA.
MRC Dunn Human Nutrition Unit, Wellcome Trust/MRC Building, Hills Road, Cambridge CB2 2XY, United Kingdom.

This study can be accessed at: http://www.ncbi.nlm.nih.gov/pubmed/15159299

The study investigated the association between soy phytoestrogens (such as daidzein and genistein) and breast cancer. The study included 333 women (aged 45-75 years) who were followed for up to eight years.

The study found:
(a) Women who consumed the highest levels of daidzein had a 17.6% increased risk of breast cancer compared to women who consumed the lowest levels of daidzein.
(b) Women who consumed the highest levels of genistein had a 16.5% increased risk of breast cancer compared to women who consumed the lowest levels of genistein.

The results from the study show that high dietary intake of soy (daidzein and genistein) are associated with an increased risk of breast cancer.

Women eating increasing amounts of soy have a higher risk of breast cancer

This study was published in the British Journal of Cancer 2003 Oct 6;89(7):1255-9

 

Study title and authors:

Flavonoid intake and breast cancer risk: a case--control study in Greece.

Peterson J, Lagiou P, Samoli E, Lagiou A, Katsouyanni K, La Vecchia C, Dwyer J, Trichopoulos D.

Schools of Nutrition and Medicine, Boston, MA 02111, USA.

 

This study can be accessed at: http://www.ncbi.nlm.nih.gov/pubmed/14520456

The study investigated the association between flavonoids and the risk of breast cancer. The study included 820 women with breast cancer and 1,548 control women without breast cancer.

Regarding isoflavones, (the overwhelming dietary source of isoflavones are from soy products, see table below), the study found that for every 0.8 mg per day increase in isoflavones there was a 7% increase in breast cancer.

Isoflavones contents of food

Below are isoflavones contents (total isoflavones, daidzein and genistein) of foods taken from the USDA database. Values of isoflavones are expressed in mg per 100g.

Food product	Total isoflavones	Daidzein	Genistein
Soy flour, full-fat	177,89	71,19	96,83
Soy flour, textured	148,61	59,62	78,90
Soy flour, defatted	131,19	57,47	71,21
Soybeans	128,34	46,46	73,76
Soy protein concentrate, aqueous washed	102,07	43,04	55,59
Soy protein isolate	97,43	33,59	59,62
Natto	58,93	21,85	29,04
Soybean chips	54,16	26,71	27,45
Tofu, fried	48,35	17,83	28,00
Tempeh	43,52	17,59	24,85
Miso	42,55	16,13	24,56
Soybean sprouts	40,71	19,12	21,60
Tofu, soft	29,24	8,59	20,65
Tofu, silken	27,91	11,13	15,58
Soy infant formula, powder	25,00	7,23	14,75
Tofu, firm	22,70	8,00	12,75
Soy hot dog	15,00	3,40	8,20
Okara	13,51	5,39	6,48
Soy protein concentrate, alcohol extracted	12,47	6,83	5,33
Bacon, meatless	12,10	2,80	6,90
Soy milk	9,65	4,45	6,06
Vegetarian burger	9,30	2,95	5,28
Soy cheese, Mozzarella	7,70	1,10	3,60
Soy cheese, Cheddar	7,15	1,80	2,25
Soy drink	7,01	2,41	4,60
Split peas	2,42	2,42	0,00
Shoyu	1,64	0,93	0,82
Pigeon peas	0,56	0,02	0,54
Clover sprouts	0,35	0,00	0,35
Peanuts	0,26	0,03	0,24
Navy beans	0,21	0,01	0,20
Mung beans	0,19	0,01	0,18
Granola bars	0,13	0,05	0,08
Chickpeas	0,10	0,04	0,06
Green tea	0,05	0,01	0,04
Broadbeans	0,03	0,02	0,00
Cowpeas	0,03	0,01	0,02
Lima beans	0,03	0,02	0,01
Lentils	0,01	0,00	0,00
Alfalaval seeds, sprouted	0,00	0,00	0,00
Black beans	0,00	0,00	0,00
Flax seed	0,00	0,00	0,00
Rye bread	0,00	0,00	0,00

Soy consumption increases the risk of breast cancer

This study was published in Cancer Epidemiology, Biomarkers and Prevention 2005 Jan;14(1):81-90

Study title and authors:

Food and botanical groupings and risk of breast cancer: a case-control study in Shanghai, China.

Shannon J, Ray R, Wu C, Nelson Z, Gao DL, Li W, Hu W, Lampe J, Horner N, Satia J, Patterson R, Fitzgibbons D, Porter P, Thomas D.

Oregon Health and Sciences University, Public Health and Preventive Medicine, 3181 Southwest Jackson Park Road, CSB669, Portland, OR 97239, USA. shannoja@ohsu.edu

This study can be accessed at: http://www.ncbi.nlm.nih.gov/pubmed/15668480

The study investigated the association of diet with the incidence of breast cancer. The study included 378 women with breast cancer and 1,070 controls.

The study found:
(a) Women that ate the most unfermented soyfoods had a 22% increased risk of breast cancer compared to women who ate the least unfermented soyfoods.
(b) Women that ate the most eggs had a 46% decreased risk of breast cancer compared to women who ate the least eggs.

The data from the study shows that unfermented soyfood consumption increases the risk of breast cancer whereas egg consumption lowers the risk of breast cancer.