How are your vitamins, minerals and supplements interacting with your cancer meds?

Published: 22 Jan 2020

Most of us do our best to stay healthy and may take vitamin, mineral or herbal supplements on a daily basis, or when we feel our bodies need a boost.  When we’re ill or fighting a serious disease such as cancer, we are even more likely to try and find ‘herbal remedies’ and supplements to help us... and why not?  

Cancer, the side-effects of the illness as well as the treatment itself, can deplete our bodies of the nutrients we so badly need.  It’s estimated that between 65% to 80% of cancer patients already use supplements.

But before you load up on any vitamins, minerals and supplements or other remedies, do your research!  Many ingredients can clash with chemo, radiation therapy and other medications prescribed by your medical team.

The popularity of herbal remedies and supplements

Herbal remedies have been staples in the sickroom and the kitchen for centuries before big-pharma meds. Supplemental vitamins in pill form have been available for more than 50 years.

Today, there is a vast array of tablets and potions containing vitamins, minerals, herbs, spices, nuts, seeds and other compounds that come from natural sources all widely available. There are holistic specialists, homeopaths, Chinese herbalists all using natural ingredients to treat an array of ailments. According to a US government survey, approximately 38 percent of adults in the US reported using complementary and alternative medicine in the past 12 months.  

Although most natural remedies are safe when not taken whilst on any other medications, what many people fail to realize is that they can interact with more traditional drug regimens prescribed by a doctor.

Be safe, not sorry 

Our bodies are complex machines and everyone's genetic make-up is different.  Even when we are well, what benefits one person may not benefit another and can even have a negative effect..  

Similarly, cancer patients are individually prescribed a unique range of drugs depending on their specific illness and other pre-existing conditions, allergies, genetic make-up and their body’s individual needs.

Chemotherapeutic drugs are strong medications designed to target rapidly dividing cancer cells. Most patients will be prescribed a concoction of different drugs. These drugs work together in a symbiotic relationship, interacting with each other in a way that’s designed to deliver a positive end-result.   The introduction of another ingredient to the mix, even a natural one that you may have taken for years, can create an imbalance.  This can result in the treatment becoming less effective, having a negative reaction or side effect, or worse still, it may cause harm. 

Herbal and natural remedies are a vast subject that is still not fully researched or understood, especially when it comes to mixing natural remedies with pharmaceutical medications.  This is why it's so very important to seek advice from your medical team. Even then, this a largely untapped area, so don't be surprised if they simply don't know. They may advise you to abstain from taking anything whilst on cancer meds. Better safe than sorry.

If you have cancer you will no doubt have found that friends, family, support groups and even strangers are keen to offer well-intentioned advice. They may recommend supplements and remedies with reassuring words such as ‘it worked for me’' and ‘my doctor says it’s fine.’  But you are unique and so is your drug regimen – so always check with your medical team.

“Drugs or supplements that a person normally takes without any concern can be problematic for a person with cancer,” said Ila M. Saunders, PharmD, an assistant clinical professor at the Skaggs School of Pharmacy and Pharmaceutical Sciences at the University of California San Diego and an oncology clinical pharmacist at UC San Diego Health.

“Be sure to discuss everything you are taking with your health care team so they can give you the best treatment possible. Many OTC and herbal supplements can harmfully interfere with chemotherapy treatments.” 

Vitamins and supplements to avoid

As we've mentioned, the subject is vast, and we're not experts in the field.  But we've listed some of the better-known vitamins and ingredients that many of the reputable cancer advice websites are advising chemo patients to avoid.  

These are just a few and there are many others.  You may need to avoid these supplements and vitamins for a period of time during your treatment but often after treatment, you will be able to take again.   Our advice as always is to check with your medical team.

Top Tips

  1. Your cancer treatment center or hospital may have an integrative medicine division. That's a good place to start if you want to know what herbs, teas, or nutritional supplements can help you stay strong and cope with treatment side effects.
  2. Research and ask your treatment team about supplements for your specific situation. Most supplements have not been studied extensively in large clinical trials. It’s important to choose wisely and be informed.
  3. Ask your oncology and medical team
    • Does my chemotherapy interact with any of my other medications?
    • Does my chemotherapy or other meds interact with any foods or beverages?
    • What herbal supplements, vitamins, or over-the-counter medications can I take safely with this medicine?
  4. Eat a healthy, well-balanced diet including lots of plant-based foods such as whole grains, fruits and vegetables-is most strongly and consistently associated with cancer reduction and lower recurrence rates. (Rogel Cancer Centre). But always check with your medical team about whether or not there are any foods you should avoid.

To access support and advice from a friendly community of over 6,000 people dealing with cancer and chemo right now, join the Facebook Chemotherapy Support Group.

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