Vitamins, Minerals, Herbs and Supplements: A Blinking Red Light for People with Cancer

3D rendering of periodic elements inside pill capsules
Pictured: The best way to get vitamins and minerals is through a healthy diet rich in whole grains, vegetables and fruits. Be sure to consult with your physician before taking any over-the-counter vitamins or supplements.

Many people affected by cancer are intent on strengthening their immune systems in order to fight the disease, tolerate treatment or prevent infections. These are worthy goals that should be approached with the same thought and caution you use to make other important medical decisions.

Many of us grew up thinking that ingesting a variety of vitamins and minerals would help us stay healthy. And we figured that almost anything herbal was safe simply because it grows in the wild and is natural. These myths are not only false, but they can be unsafe. Research and clinical studies routinely show that the way our bodies and cancer cells respond to these substances is unpredictable, complex and sometimes dangerous.

We’ve all read about the “virtues” of such notorious miracle cancer cures as shark cartilage, Kanglaite, or cannabis oil on the Internet. It’s easy to recognize that the claims are dubious and the stories are fantasy. But when our friends report their own health success with a favorite tea or the latest chewable vitamin, it’s harder to resist trying them ourselves. If you’re being treated for cancer, however, this may be the time to “just say no.”

Consider this:  if vitamins, minerals, herbs or supplements are being recommended to improve your health, it means they’re not perceived as benign. This very possibility is why you MUST discuss with your physicians anything you’re considering taking before you do so. The best way to get vitamins and minerals is through a healthy diet rich in whole grains, vegetables and fruits. Getting your vitamins from whole foods ensures that you get other plant chemicals that can be beneficial for health at levels your body needs.

Every day, new and surprising research is teaching us more about the ways cancer cells act and evolve, the ways they interact with our organs and respond to therapies. In fact, a few years ago, Roswell Park researchers identified genetic variations associated with higher vitamin D levels in African-American women that were linked to fewer aggressive breast cancers. So, if individual differences can be helpful, it is also possible that they can magnify harmful effects. Using this kind of knowledge, our medical care teams devise treatment plans that reflect the latest proven findings. You can, and should, participate in your treatment by informing your team when you comply, ignore or edit the plan. With open and honest communication between everyone on the care team, you can be confident you have the information needed to make the best treatment decisions for you. 

To learn about the use of vitamins, minerals, herbs and supplements in complementary cancer therapies, the following resources are recommended:

National Cancer Institute

                 Topics in Complementary and Alternative Therapies

                  Botanicals & Herbal Products

                  Nutritional Therapies

                  Questions to Ask Your Health Care Provider About CAM

National Center for Complementary and Alternative Medicine

                  Herbs at a glance

Office of Dietary Supplements, National Institutes of Health (ODS)

American Cancer Society's Herbs, Vitamins, and Minerals