It’s a top question on the minds of many cancer survivors: What will help keep the cancer from coming back? Unfortunately, conventional medicine often doesn’t have much of an answer beyond, “Take care of yourself, and try not to worry.” Naturopathic medicine, however, does have some specific recommendations for cancer survivors—and dietary supplements play a key role. The reason: “Dietary supplements are able to fit into the “nooks and crannies” of our biochemical pathways, creating specific changes that influence our bodies on a cellular level,” said Lise Alschuler, ND, a breast cancer survivor and coauthor of The Definitive Guide to Thriving After Cancer. The five supplements listed below comprise what Dr. Alschuler calls a “foundational supplement plan” for just about every cancer survivor—and for just about every person who wants to reduce the odds of ever getting cancer in the first place. Each of the five supplements helps reduce cancer risk through five key pathways…

  • Boosting immune system function.
  • Reducing inflammation.
  • Improving insulin sensitivity.
  • Supporting digestion and detoxification.
  • Reducing stress-induced hormone imbalances.

Although dietary supplements are available over-the-counter, before you start taking them, it is essential to check with a naturopathic doctor (ideally one with additional board certification in naturopathic oncology) or an integrative medical doctor with specific expertise in integrative cancer care. These providers have training in nutritional biochemistry as it relates to cancer. They can confirm that the following supplements are appropriate for you and determine the dosages and the specific brands that will best suit your needs.

For her own post-cancer patients, Dr. Alschuler typically prescribes all five of the following supplements, to be taken daily starting as soon as conventional treatment is completed. “Some patients may be advised to start taking some of these supplements during their conventional treatment, but that should be done only under the guidance of an integrative health-care physician,” she said.

The top five cancer fighters include…

Omega-3 fatty acids. These essential fatty acids—found in supplements of fish oil, flaxseed oil and algae-based oil—positively influence all five of the key pathways mentioned above. However, they are especially important for reducing chronic inflammation, which is one of the precursors of cancer. “Think of inflammation as a burning ember in your body that can change your tissues in ways that favor the growth of abnormal cells. Omega-3s quench that fire,” Dr. Alschuler said. Though omega-3s are helpful for survivors of all types of cancer, studies show particular benefits for patients who have battled colon, prostate, breast or lung cancer. A typical daily dosage is 1,000 mg to 3,000 mg of omega-3 oil.

Caveat: Omega-3s can increase bleeding, so it’s vital to get your doctor’s OK before taking omega-3s if you are on blood-thinning medication or are anticipating any surgery.

Probiotics. Beneficial bacteria in the intestinal tract help metabolize nutrients, bind waste products for removal in stool and regulate immunity. When beneficial bacteria are depleted, the digestive tract is overrun with harmful bacteria and a condition called dysbiosis develops. This negatively impacts all five of the body’s key pathways, contributing to an increased risk for cancer recurrence. Studies have shown that supplementing with beneficial intestinal bacteria called probiotics can reduce the risk for infection after surgery and improve the immune system’s response. You can get some probiotics from eating yogurt and fermented foods such as fresh sauerkraut, miso, tempeh and kefir. However, to fully support her patients’ beneficial digestive bacteria, Dr. Alschuler typically prescribes a supplement that combines several types of probiotics at a dosage of at least one billion colony-forming units (CFU) daily.

Caution: Probiotics are not appropriate for people whose white blood cell count is below normal—some evidence suggests that probiotics can increase the risk for blood infection in those individuals.

Polyphenols. Healthful, colorful fruits and vegetables get their rainbow hues from the naturally occurring plant compounds called polyphenols (also referred to as flavonoids). According to Dr. Alschuler, three polyphenols are particularly important in the fight against cancer…

  • Green tea catechins, which may lower the risk for cancers of the digestive tract, breast, bladder, lung, blood and prostate.
  • Curcumin, the bright yellow flavonoid found in turmeric root, which appears to inhibit cancer formation in a variety of ways, helping protect against the majority of cancer types.
  • Resveratrol, which gives color to red grapes and some berries, has shown promise against breast, colorectal and liver cancers by activating tumor suppressor genes and increasing the rate of apoptosis (normal programmed cell death).

Your doctor may prescribe a combination supplement that contains all three of these polyphenols, or you may take each one separately. “Many high-quality brands also include other polyphenols. But watch out for what I call ‘window-dressing’ supplements that list 20 to 30 different polyphenols—because the amount of each one will be so small that you might as well just eat a salad,” Dr. Alschuler said.

Antioxidants. “Look at metal that’s been exposed to rain and sunlight—it starts to rust because it’s being oxidized. That’s essentially what happens to our bodies from exposure to ‘free radicals,’ or oxidative toxins,” Dr. Alschuler said. Antioxidants guard against this by binding to oxidative toxins so they can be eliminated…and they also stimulate cell repair and normal apoptosis. Cancer treatment can deplete your antioxidant capacity because cancer drugs themselves exert their cancer-killing effects via oxidation. A plant-based diet provides antioxidants, but cancer survivors should get additional support by taking…

  • Glutathione, the body’s “master antioxidant,” which is critical for the elimination of environmental toxins. A typical dosage is 250 mg to 500 mg daily.
  • Coenzyme Q10 (CoQ10), which is associated with decreased risk for breast and thyroid cancer, as well as melanoma, studies show. A typical daily dosage is 30 mg to 100 mg.

Vitamin D. Numerous studies have shown the cancer-preventing potential of this vitamin, which promotes proper cell maturation and regulates inflammation, among other activities. “Without adequate levels of vitamin D, it’s hard for our bodies to maintain good blood sugar control or reduce inflammation,” said Dr. Alschuler. Although it’s often called the sunshine vitamin, many people in the northern hemisphere cannot get enough vitamin D just from being outdoors, especially during cooler seasons. Ask your doctor to measure your blood level of vitamin D—that information will help determine the right dosage for you.

Caution: If you take the heart medication digoxin, be especially sure to talk with your doctor before taking vitamin D because the combination could lead to abnormal heart rhythms.

Important: “Dietary supplements are called ‘supplements’ for a reason—they are meant to supplement the diet, not to replace healthy eating,” Dr. Alschuler said. “Over time, they provide targeted molecular support that gently but radically alters the terrain in your body, creating an environment that impedes cancer recurrence…so you can get back to the business of living your life.”