have received conflicting advice regarding the use of supplemental antioxidants
like vitamin C during my chemotherapy and radiation therapy.
(1) Should I avoid them or take them?
Does this concern extend to the ingestion of foods containing high
levels of antioxidants, like any food (such as an orange or orange
juice) that has a high amount of vitamin C?
The use of various
dietary supplements (vitamins, antioxidants, herbs, etc) by people with
a cancer diagnosis is very common. Some reasons given for their use
unpleasant symptoms from the disease itself or side effects from the
2. Protect normal healthy cells from side effects produced by treatments
3. Enhance healing after surgery
4. Augment the effects from conventional cancer treatments
5. Prevent recurrence of the original cancer and/or a new primary
6. Detoxify the body both during therapy and recovery
7. Enhance the immune system
of the above reasons have some intuitive merit. However, data from<
well-designed research studies are not plentiful to help guide choices
of dietary supplements for a particular type and stage of cancer,
dosing, timing, interactions with other therapy/drugs, etc. The number
of products available in a health food store and for sale on the
Internet is mind-boggling. Where to start? Where to stop?
consider the concern regarding the use of antioxidants during cancer
therapy the most controversial question in nutritional oncology at this
time. Does the ingestion of dietary supplements that are antioxidants
(such as vitamin C, vitamin E, selenium, and many others) increase,
decrease, or have no effect on the potential benefits of chemotherapy,
radiation therapy, and other biological or hormonal therapies?
supplements are often recommended by popular books and some
individual health care practitioners to use during cancer therapy in
order to help protect the body's normal cells from the harmful side
effects of chemotherapy and radiation. While this outcome is certainly
desirable, the real question is how this practice might affect the
potentially beneficial result intended from the use of chemotherapy
radiation therapy (i.e., help extend life with an acceptable level of
quality of life). One mechanism of killing cancer cells is the
generation of a massive amount of free radicals within the cancer cell
by various chemotherapy drugs and radiation in order to disrupt
replication and growth of the cancer cells. Thus there is concern by
many oncologists that consuming additional supplemental antioxidants,
which eliminate free radicals, may potentially reduce the effectiveness
and defeat the very purpose of choosing to undergo conventional cancer
therapies like radiation and chemotherapy.
research still needs to be done to evaluate this question in
clinical trials (human data). Although preliminary research has been
done in both in test tubes and animals, human testing is the only way
really know how the addition of various dietary supplements to a
conventional cancer therapy will affect survival and quality of life.
the meantime, the question of what to do still looms. There are no
best advice I can give you is to READ, READ, READ (cross check
everything - do not believe everything you read!), and be the patient
with 10,000 questions. Determine your goals and then use the questions
have outlined in my "Decision Tree" (on page 15 of my book)
springboard for being an informed and savvy cancer patient. NEVER use
one source of information as your only source of information,
particularly if that source has a financial interest in the product
being sold! Invest much more research time deciding what to put into
your body than you have in the past when buying a home or car. You are
trying to choose a course of action that offers reasonable hope, instead
of hype, or even possible harm.
the choice of what to do is a personal one. However, I
strongly recommend discussing possible choices regarding the use of
dietary supplements with members of your oncology team, particularly
your physicians, dietitian and pharmacist. Ask them to share their
thought process and references that have led to their recommendations.
Also ask them to help you understand and interpret the scientific
strength of advice, articles or information you may have found in
various books, from the Internet, or from other practitioners.
books, articles, and web sites to read as starting points for
information regarding the use of herbs, vitamins, and other dietary
supplements in cancer:
against Cancer, Ralph Moss, PhD, Equinox Press, 2000.
2.Choices in Healing - Integrating the Best of Conventional and Complementary
Approaches to Cancer, Michael Lerner, PhD, MIT Press, 1994.
3. Dietary Options for Cancer Survivors: A guide to research on foods, food substances, herbals and dietary regimens that may influence cancer, American Institute for Cancer Research, Washington, DC, 2002.
4.Herbal Medicine, Healing & Cancer, Donald Yance, Keats Publishing,
5.Herbs against Cancer, Ralph Moss, PhD, Equinox Press, 1998.
6.Fight Cancer with Vitamins and Supplements: A Guide to Prevention
and Treatment, K.N. Prasad, PhD, and K.C.Prasad, MD, Healing Arts
Press, Rochester, VT, 2001.
7.Natural Compounds in Cancer Therapy, John Boik, Oregon Medical Press,
Princeton, MN, 2001.
8.Tylers Herbs of Choice - The Therapeutic Use of Phytomedicinals,
James Robbers, PhD, and Varro Tyler, PhD, ScD, Haworth Press, 1999.
9.Tylers Honest Herbal: a Sensible Guide to the Use of Herbs
and Related Remedies, Tyler and Steven Foster, Pharmaceutical Products
Press, New York, 1998.
for Alternative Medicine Research in Cancer
for Complementary and Alternative Medicine (CCAM)
of Dietary Supplements (NIH)
(Dr. Stephen Barrett)
interactions between dietary antioxidants and chemotherapy",
Labriola D, and R Livingston, Oncology (Huntingt) 1999
July;13(7):1003-8, discussion 1008, 1011-12. Comments in Oncology
(Huntingt) 1999 Dec;13(12):1624, 1627-28, 1631.
in cancer therapy; their actions and interactions with oncologic therapies",
Lamson, D and M Brignall, Alternative Medicine Review 4(5):304-329,
1999. Full article available on line.
and Cancer Therapy II: Quick Reference Guide
Davis W. Lamson, MS, ND, Matthew S. Brignall, ND
Alternative Medicine Review 2000 Apr;5(2):152-63.
A summary with charts of the more lengthy review cited above (Altern
Med Rev. 1999 Oct;4(5):304-29) - this summary available
Supplementation for Patients With Metastatic Cancer - Nutrition and
Cancer 38(2):296-298, 2000.
Antioxidants During Cancer Chemotherapy: Impact on Chemotherapeutic
Effectiveness and Development of Side Effects - Nutrition and Cancer
J Pediatr Hematol Oncol. 2007 Jan;29(1):32-47.
A strategy for controlling potential interactions between natural health products and chemotherapy: a review in pediatric oncology.
Seely D, Stempak D, Baruchel S. Article available on-line.
are additional books and websites on the Links
page of my website. Inclusion here is simply meant as a source of
information to evaluate further, not an endorsement.
answering your second question regarding concern about the
consumption of foods high in antioxidants, I know of no large body of
research that would lead me to conclude at this time that any food
should be specifically avoided during cancer therapy because of its
content of antioxidants. It is the ingestion of individual antioxidants
in the isolated form of a pill, often in doses significantly higher
obtained from usual amounts of food sources, that is of greater concern.
The consumption has now changed, in essence, from a nutrient level to
pharmaceutical (drug) level.
from the sale of my books are donated to the Diana Dyer Cancer
Survivors' Nutrition and Cancer Research Endowment that I have
established at the American Institute for Cancer Research (AICR) in
Washington, DC. I direct this endowment to exclusively fund research
projects that will focus on defining nutritional strategies after a
cancer diagnosis, either during treatment or recovery, which will
optimize the chances for long-term survival.
first research project that my endowment has helped to fund through
AICR will be evaluating the outcome (i.e. the effectiveness of
chemotherapy on extending life) of adding an antioxidant to a specific
chemotherapy regime in humans. Much more research of this type should
funded by our government's National Cancer Institute to help cancer
patients and physicians optimize cancer therapy.
regarding additional donations to this endowment or grant applications
may be obtained from the Director of Development at AICR by calling
12/01, updated 10/02, 1/04, 3/07
to Main QandA
Concerns during Cancer Treatment (related
to side effects)
you provide a list of all chemotherapy drugs called alkylating agents that
may potentially have interactions with antioxidant supplements during chemotherapy?
Diana, I am undergoing treatments for cancer and am not eating well. What
should I do? posted
I drink your soy shake recipes if my oncologist or dietitian has recommended
that I follow a neutropenic diet due to my low white blood cell counts?
5/00, updated 7/01, updated 11/02, updated 8/03
I consume antioxidants during my cancer therapy? posted
12/01, updated 10/02
herbs interact with any of the chemotherapy drugs? posted
4/01, updated 9/02
there any diet changes to help relieve bloating during abdominal radiation?
you have diet suggestions for someone who has diarrhea after
radiation therapy for rectal cancer? posted
1/04, updated 4/04, 11/04, 1/05
it safe to drink green tea if I have a port for administration of my chemotherapy?
you tell me foods to eat to reduce the acid in my urine and pain in my bladder
and ureters? posted
2/04, updated 5/05
can I eat a diet as healthy as you suggest if I need to be
hospitalized for more than a day or two? posted
husband is having chemotherapy treatments and has lost his sense
of taste after one treatment. Are there any foods I can prepare that will
give him some relief?
there a good web site describing the nutrition related side effects from
chemo drugs? posted
I stop drinking green tea during chemotherapy to avoid consuming too many
antioxidants? posted 7/05
can I use the diet recommendations on your web site and in your book
to both increase my intake of cancer fighting foods for optimizing
my cancer recovery and lose weight at the same time? posted
tips do you have to stay on a healthy diet during the holiday season? posted
to Main QandA Page
have recently seen a lot of news articles about the relationship between
vitamin D and cancer prevention. Should we all run out and get more
Vitamin D supplements? posted
am being treated for bladder cancer. I have heard that vitamins that
might help me reduce my risk of recurrence. Do you know anything
about this? posted 8/02
, updated 11/05
you have recommendations for herbs and vitamins that children should
use to recover from a bone marrow transplant? posted
you provide a list of all chemotherapy drugs called alkylating agents
that may potentially have interactions with antioxidant supplements
during chemotherapy? posted
I consume antioxidants during my cancer therapy? posted
12/01, updated 10/02
I stop drinking green tea during chemotherapy to avoid consuming too
many antioxidants? posted 7/05
have recently heard that Vitamin A may be linked to osteoporosis. I
see Vitamin A in nearly everything on food labels, even my soymilk.
What is the connection and how much should I be consuming? posted
5/02, updated 2/03
These questions and answers
are intended to be of a general informative nature. Please consult with
the Registered Dietitian in your cancer center or your health care provider
for nutritional advice that can be individualized to your specific medical