Cancer and Natural Remedies: What to Tell Your Care Team

You are not being judged for wanting to help yourself. NCI notes that people with cancer use complementary approaches to cope with side effects, comfort themselves and ease worry, feel that they are doing something for their own care, or to try to treat or cure their cancer. [1] The safest step is to tell your oncology team about everything you use, including vitamins, teas and herbs, because things that seem safe could be harmful or even interfere with cancer treatment. [1] If you are in emotional crisis or thinking about harming yourself, call 988 (US Suicide & Crisis Lifeline). In a medical emergency, call 911.

What the main sources say

• NCCIH: no complementary health approach has been shown to prevent or cure cancer. [2]
• NCCIH: do not use unproven products or practices to replace or delay medical treatment for cancer. [2]
• NCCIH: some herbs may make chemotherapy drugs less effective. [2]
• NCI: some of these products can change how your cancer treatment works. [1]

None of this says a remedy is useless for every purpose, and none of it says to give up comfort measures you value. It says the care team needs to know.

Supportive approaches versus supplements

Supportive approaches are not the same as products you swallow. NCCIH says some approaches, such as acupuncture, mindfulness-based stress reduction and yoga, may help manage cancer symptoms and side effects of treatment. [2] Those are practices, covered in Therapies & Traditions. This page is about natural products.

Medicines: documented interactions

NCCIH says St. John's wort can weaken some cancer medicines, naming irinotecan, imatinib and docetaxel. [3] It can also weaken medicines for HIV, transplant rejection and more, which is why it appears on many lists. [3] See St. John's wort interactions and the fuller supplements and cancer treatment guide. Proper evidence not found here for a complete list of herb and chemotherapy pairs; NCI and NCCIH both point readers to the care team rather than a list.

Delay of care is a documented harm

A 2018 US study (JAMA Oncology) used National Cancer Database data on people with non-metastatic breast, prostate, lung or colorectal cancer. [4] It looked at people who also received "Other-Unproven" treatments given by non-medical personnel, not at supplements specifically. [4] It found those people had poorer five-year survival, and that the extra risk was linked to refusing conventional treatment, because the link with survival disappeared once treatment delay or refusal was included in the model. [4] This is a retrospective observational study, so it cannot prove cause, and only 258 people were in the group of interest, but it fits NCCIH's warning that delaying treatment reduces the likelihood of remission or cure. [2]

Cancer "cure" claims and red flags

FDA says illegal cancer products come as pills, capsules, powders, creams, teas, oils and treatment kits, and are often advertised as "natural" or falsely labeled as dietary supplements. [5] They may delay or interfere with proven treatments and may contain dangerous ingredients. [5] FDA's list of red-flag phrases includes "more effective than chemotherapy." [5] FDA's page on illegally sold cancer treatments lists warning letters to companies selling more than 80 products with such claims. [6] FDA also says there are legal ways to get investigational treatments, such as clinical trials; talk to your doctor about them. [5] Use how to check claims on social media and evaluating safety claims.

Questions to bring to your team

• Is this product likely to change how my treatment works?
• Should I tell the surgical or radiation team too? (See supplements before surgery.)
• Can the pharmacist check each product against my chemotherapy or hormone therapy?
• Does the product have any quality check? See quality testing and certifications.

Always tell your doctor which complementary approaches you use, including over-the-counter and prescription medicines. [1] Return to Existing Health Conditions.