A quick Google search of “turmeric and cancer” reveals a wide variety of headlines touting the natural spice as “cancer-fighting” and a “universal cancer treatment.”
An Indian spice derived from the plant Curcuma longa, turmeric, and its active ingredient curcumin, have been studied in a wide variety of diseases, including cancer. Yet much of the data available on the efficacy of turmeric and curcumin in cancer are taken from laboratory or animal studies, or very early-phase trials in humans.
Evidence in Favor
A 2011 study found that the administration of oral curcumin prior to surgery improved cachexia and general health of patients with colorectal cancer.1 In patients with prostate cancer, a small study showed that a supplement of blended pomegranate, green tea, broccoli, and turmeric had a short-term effect on the percentage rise in prostate-specific antigen (PSA) in men under active surveillance or watchful waiting after a PSA relapse post-radical treatment.2
More recently, a study found that a small dose of curcumin significantly decreased the proliferation of glioblastoma multiforme.3 The curcumin targeted glioblastoma stem cells through induction of ROS and potentially through the down-regulation of STAT3 activity. The researchers concluded that curcumin “may be a safe future chemotherapeutic agent for the treatment of glioblastoma.”
Another small study showed that oral curcumin reduced the severity of radiation dermatitis in patients with breast cancer.4
A recent review found that there have been more than 120 clinical trials of curcuminoids against several diseases both in vitro and in vivo, but that no clinical trial of curcumin has been successful.5 In their review, the researchers wrote that “no form of curcumin, or its closely related analogues, appears to possess the properties required for a good drug candidate (chemical stability, high water solubility, potent and selective target activity, high bioavailability, broad tissue distribution, stable metabolism, and low toxicity).”
The authors added that they believe that much of the research into curcumin is “much ado about nothing” and that “low systemic exposure levels reported in clinical trials do not support its further investigation as a therapeutic.”
Finally, supplementation with turmeric and curcumin may not be without harm. Laboratory findings show that dietary turmeric may actually inhibit the anti-tumor activity of chemotherapeutic agents such as cyclophosphamide and doxorubicin.6
These studies show that more research is needed to determine the effects of turmeric and curcumin in cancer. There is also no consensus of how much of the supplement would need to be consumed to have an effect, and it is likely that its effects would vary from person to person.
Based on the available data, Timothy J. Moynihan, MD, a medical oncologist at the Mayo Clinic in Rochester, Minnesota, says that “at this time, there isn’t enough evidence to recommend curcumin for preventing or treating cancer.”7
- He ZY, Shi CB, Wen H, Li FL, Wang BL, Wang J. Upregulation of p53 expression in patients with colorectal cancer by administration of curcumin. Cancer Invest. 2011;29(3):208-13.
- Thomas R, Williams M, Sharma H, Chaudry A, Bellamy P. A double-blind, placebo-controlled randomized trial evaluating the effect of a polyphenol-rich whole food supplement on PSA progression in men with prostate cancer—the U.K. NCRN Pomi-T study. Prostate Cancer Prostatic Dis. 2014;17(2):180-6.
- Gersey ZC, Rodriguez GA, Barbarite E, et al. Curcumin decreases malignant characteristics of glioblastoma stem cells via induction of reactive oxygen species. BMC Cancer. doi: 10.1186/s12885-017-3058-2 [Epub ahead of print]
- Ryan JL, Heckler CE, Ling M, et al. Curcumin for radiation dermatitis: a randomized, double-blind placebo-controlled clinical trial of thirty breast cancer patients. Radiat Res. 2013;180(1):34-43.
- Nelson KM, Dahlin JL, Bisson J, Graham J, Pauli GF, Walters MA. The essential medicinal chemistry of curcumin. J Med Chem. 2017 Jan 11. doi: 10.1021/acs.jmedchem.6b00975 [Epub ahead of print]
- Somasundaram S, Edmund NA, Moore DT, Small GW, Shi YY, Orlowski RZ. Dietary curcumin inhibits chemotherapy-induced apoptosis in models of human breast cancer. Cancer Res. 2002;62(13):3868-75.
- Moynihan TJ. Can curcumin slow cancer growth? Mayo Clinic website. http://www.mayoclinic.org/diseases-conditions/cancer/expert-answers/curcumin/faq-20057858. Published February 8, 2017. Accessed February 8, 2017.