Garlic and Cancer - are there benefits?

Garlic Dietary Impacts on Colon Cancer and Colorectal Cancer

I did a review of the medical journals on the impact of fresh garlic and colon cancer and colorectal cancer.

Summary of studies suggesting garlic reduces the risk of colon cancer and colorectal cancer.

Studies that suggest garlic consumption reduces the risk of colon cancer and colorectal cancer.[i] [ii] [iii] [iv] [v]

Studies that suggest garlic consumption reduces the risk of colorectal cancer.[vi]

Garlic consumption does not reduce the risk of colon cancer summary.
Research evaluation in process – through 2013

Garlic consumption does not reduce the risk of colon cancer.[vii] [viii]

Garlic consumption does not reduce the risk of colorectal cancer.[ix] [x]

Garlic consumption increases the risk of colon cancer.

Being overweight and consuming garlic increases the risk of colon cancer.[xi]

Increased risk in colon cancer in women.[xii]

Garlic Supplements and All Cancers.

Garlic supplements don’t seem to reduce the risk of cancers.[xiii] Garlic supplements don’t impact the risk breast cancer.[xiv] Garlic supplements don’t impact the risk of colon cancer and rectal cancer.[xv]

Taking garlic supplements for H-pylori stomach infection decreased risk of gastric cancer.[xvi] Not drinking alcohol was associated with a stronger beneficial effect of garlic supplementation on gastric cancer prevention.[xvii] Aged Garlic Extract was effective in reducing the number and magnitude of colorectal adenomas in one randomized control trial.[xviii]

Garlic supplements increase the risk of colorectal cancer.[xix] Garlic supplements were not found to be significantly associated with an increased risk of cancer.[xx] A non-significant protective effect of garlic supplement intake against colorectal cancer was observed in females but increased the risk in males.[xxi] People that smoke and take garlic supplements have a higher risk of lung cancer.[xxii] Garlic supplements were associated with a statistically significant 35% elevated colorectal cancer risk.[xxiii]

Reference Sources

[i] Wang Y, Huang P, Wu Y, et al. Association and mechanism of garlic consumption with gastrointestinal cancer risk: A systematic review and meta-analysis. Oncol Lett. 2022;23(4):125. doi:10.3892/ol.2022.13245

[ii] Fleischauer AT, Arab L. Garlic and cancer: a critical review of the epidemiologic literature. J Nutr. 2001;131(3s):1032S-40S. doi:10.1093/jn/131.3.1032S

[iii] Wang Y, Huang P, Wu Y, et al. Association and mechanism of garlic consumption with gastrointestinal cancer risk: A systematic review and meta-analysis. Oncol Lett. 2022;23(4):125. doi:10.3892/ol.2022.13245

[iv] Aiello P, Sharghi M, Mansourkhani SM, et al. Medicinal Plants in the Prevention and Treatment of Colon Cancer. Oxid Med Cell Longev. 2019;2019:2075614. Published 2019 Dec 4. doi:10.1155/2019/2075614

[v]

[vi] Wu X, Shi J, Fang WX, et al. Allium vegetables are associated with reduced risk of colorectal cancer: A hospital-based matched case-control study in China. Asia Pac J Clin Oncol. 2019;15(5):e132-e141. doi:10.1111/ajco.13133

[vii] Wu X, Shi J, Fang WX, et al. Allium vegetables are associated with reduced risk of colorectal cancer: A hospital-based matched case-control study in China. Asia Pac J Clin Oncol. 2019;15(5):e132-e141. doi:10.1111/ajco.13133

[viii] Baena R, Salinas P. Diet and colorectal cancer. Maturitas. 2015;80(3):258-264. doi:10.1016/j.maturitas.2014.12.017

[ix] Zhu B, Zou L, Qi L, Zhong R, Miao X. Allium vegetables and garlic supplements do not reduce risk of colorectal cancer, based on meta-analysis of prospective studies. Clin Gastroenterol Hepatol. 2014;12(12):1991-e121. doi:10.1016/j.cgh.2014.03.019

[x] Hjartåker A, Aagnes B, Robsahm TE, Langseth H, Bray F, Larsen IK. Subsite-specific dietary risk factors for colorectal cancer: a review of cohort studies. J Oncol. 2013;2013:703854. doi:10.1155/2013/703854

[xi] Wang W, Dong Z, Zhang X, Li W, Li P, Chen X. Dietary and the Risk of Sporadic Colorectal Cancer in China: A Case-control Study. Iran J Public Health. 2018;47(9):1327-1335.

[xii] Zhu B, Zou L, Qi L, Zhong R, Miao X. Allium vegetables and garlic supplements do not reduce risk of colorectal cancer, based on meta-analysis of prospective studies. Clin Gastroenterol Hepatol. 2014;12(12):1991-e121. doi:10.1016/j.cgh.2014.03.019

[xiii] Fleischauer AT, Arab L. Garlic and cancer: a critical review of the epidemiologic literature. J Nutr. 2001;131(3s):1032S-40S. doi:10.1093/jn/131.3.1032S

[xiv] Dorant E, van den Brandt PA, Goldbohm RA. Allium vegetable consumption, garlic supplement intake, and female breast carcinoma incidence. Breast Cancer Res Treat. 1995;33(2):163-170. doi:10.1007/BF00682723

[xv] Dorant E, van den Brandt PA, Goldbohm RA. A prospective cohort study on the relationship between onion and leek consumption, garlic supplement use and the risk of colorectal carcinoma in The Netherlands. Carcinogenesis. 1996;17(3):477-484. doi:10.1093/carcin/17.3.477

[xvi] Li WQ, Zhang JY, Ma JL, et al. Effects of Helicobacter pylori treatment and vitamin and garlic supplementation on gastric cancer incidence and mortality: follow-up of a randomized intervention trial. BMJ. 2019;366:l5016. Published 2019 Sep 11. doi:10.1136/bmj.l5016

[xvii] Guo Y, Li ZX, Zhang JY, et al. Association Between Lifestyle Factors, Vitamin and Garlic Supplementation, and Gastric Cancer Outcomes: A Secondary Analysis of a Randomized Clinical Trial. JAMA Netw Open. 2020;3(6):e206628. Published 2020 Jun 1. doi:10.1001/jamanetworkopen.2020.6628

[xviii] Lee J, Zhao N, Fu Z, Choi J, Lee HJ, Chung M. Effects of garlic intake on cancer: a systematic review of randomized clinical trials and cohort studies. Nutr Res Pract. 2021;15(6):773-788. doi:10.4162/nrp.2021.15.6.773

[xix] Zhu B, Zou L, Qi L, Zhong R, Miao X. Allium vegetables and garlic supplements do not reduce risk of colorectal cancer, based on meta-analysis of prospective studies. Clin Gastroenterol Hepatol. 2014;12(12):1991-e121. doi:10.1016/j.cgh.2014.03.019

[xx] Zhang Q, Zhao Q, Shen Y, Zhao F, Zhu Y. Allium Vegetables, Garlic Supplements, and Risk of Cancer: A Systematic Review and Meta-Analysis. Front Nutr. 2022;8:746944. Published 2022 Mar 23. doi:10.3389/fnut.2021.746944

[xxi] Hu JY, Hu YW, Zhou JJ, Zhang MW, Li D, Zheng S. Consumption of garlic and risk of colorectal cancer: an updated meta-analysis of prospective studies. World J Gastroenterol. 2014;20(41):15413-15422. doi:10.3748/wjg.v20.i41.15413

[xxii] Dorant E, van den Brandt PA, Goldbohm RA. A prospective cohort study on Allium vegetable consumption, garlic supplement use, and the risk of lung carcinoma in The Netherlands. Cancer Res. 1994;54(23):6148-6153.

[xxiii] Satia JA, Littman A, Slatore CG, Galanko JA, White E. Associations of herbal and specialty supplements with lung and colorectal cancer risk in the VITamins and Lifestyle study. Cancer Epidemiol Biomarkers Prev. 2009;18(5):1419-1428. doi:10.1158/1055-9965.EPI-09-0038