Can Supplements Help Prevent Cancer?

Are there supplements that help prevent cancer? So far, there is no evidence that supplements can prevent or treat cancer.

However, scientists are studying several supplements for their possible risk reducing help.

The Canadian Cancer Society estimates that nearly half of all Canadians will be diagnosed with cancer at some point.<1> While that’s certainly an alarming statistic, there are many things we can do to decrease our risk.<2> Eating well, exercising regularly, getting regular medical care, living smoke free, and being sun smart are all top cancer prevention strategies. But what about supplements?

The topic of natural health products for cancer prevention is a fascinating one for researchers. Although no products on the market are proven to prevent cancer, there are some exciting ingredients that scientists are studying. As always, check with your health care practitioner to make sure a supplement is right for you. Keep in mind that those undergoing cancer treatment must be carefully supervised by a qualified health care practitioner when taking supplements.

  1. Omega-3 fatty acids

What doesn’t fish oil do? Dietary and supplemental omega-3 fatty acids have been impressing researchers for years. <3> Interestingly, science seems to point to omega-3s from fish as superior to those from flax.<4>

  1. Indole-3-Carbinol

This supplement has quite the scientific-sounding name, but just think of it as a compound derived from cruciferous veggies (such as cabbage, broccoli, kale, collard greens, cauliflower, and Brussels sprouts). When we chew, chop, or cook these delicious veggies, indole-3-carbinol (I3C) is released.<5> Although more research needs to be done, scientists suspect that I3C may help reduce certain risks posed by high estrogen levels in women. <6> In addition to eating our veggies, we can also take I3C in supplement form.

  1. Mushrooms

Who doesn’t love mushrooms? Many mushrooms, such as Agaricus blazei, Chaga, Cordyceps, Maitake, Reishi, and Shiitake are available in supplement form and are used for a variety of health purposes. Not surprisingly, given the importance of a strong immune system in fighting disesase, mushrooms are being investigated for their proven positive effect on immunity.<7>

  1. Vitamin C

Decades ago, Linus Pauling brought vitamin C into the spotlight, advocating for this hardworking vitamin and claiming that high doses could help cure certain diseases.<8> While this was refuted, today vitamin C is in the spotlight once again due to its antioxidant power. Although no conclusions have been reached, studies have examined vitamin C’s potential.<9>

  1. Curcumin

Curcumin, the active ingredient in the famous curry spice turmeric, is impressing researchers with its potential antioxidant abilities.<10>

  1. Vitamin D

Vitamin D is affectionately known as “the sunshine vitamin” because we can get it from the sun’s rays. However, it’s tricky for us to obtain sufficient vitamin D from the foods we eat, and since we in Canada don’t often get much sunshine, it’s very possible to be deficient. According to the Canadian Cancer Society, there is evidence that vitamin D may reduce the risk of some types of cancer, particularly colorectal and breast cancers and points to supplements as a good option for those of us who aren’t getting enough particularly during the winter season.<11>

Do you use any of these supplements? If you have cancer, talk to your doctor before taking any natural health products!


<1> Canadian Cancer Society. (2017). Nearly 1 in 2 Canadians expected to get cancer: report. Retrieved March 22, 2018, from

<2> Canadian Cancer Society. (2018). Can Cancer Be Prevented? Retrieved March 22, 2018, from

<3> Fabian, C. J., Kimler, B. F., & Hursting, S. D. (2015). Omega-3 fatty acids for breast cancer prevention and survivorship. Breast Cancer Research : BCR, 17(1), 62. Retrieved March 22, 2018, from

<4> Science Daily. (2018). Choose Omega-3s from fish over flax for cancer prevention, study finds. Retrieved March 22, 2018, from

<5> Linus Pauling Institute | Oregon State University. (2018). Cruciferous Vegetables. Retrieved March 22, 2018, from

<6> Linus Pauling Institute | Oregon State University. (2018). Indole-3-Carbinol. Retrieved March 22, 2018, from

<7> Guggenheim, A. G., Wright, K. M., & Zwickey, H. L. (2014). Immune Modulation From Five Major Mushrooms: Application to Integrative Oncology. Integrative Medicine: A Clinician’s Journal, 13(1), 32–44. Retrieved March 20, 2018, from

<8> Wikipedia. (2018). Linus Pauling. Retrieved April 4, 2018, from

<9> Linus Pauling Institute | Oregon State University. (2018). Vitamin C. Retrieved April 4, 2018, from

<10> Ravindran, J., Prasad, S., & Aggarwal, B. B. (2009). Curcumin and Cancer Cells: How Many Ways Can Curry Kill Tumor Cells Selectively? The AAPS Journal, 11(3), 495–510. Retrieved April 5, 2018, from

<11> Canadian Cancer Society. Should I take a vitamin D supplement? Retrieved April 5, 2018, from

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