|
Lycopene, Pomegranate, and Cancer
Prevention
“Superfoods” That Support Your Health by Aaron Katz M.D. - Healthy
Living Article
 The
pomegranate has a long tradition of use as a medicinal food, but not
many modern Americans have gone to the considerable effort involved in
eating this strikingly beautiful fruit. Now the pomegranate is hitting
the mainstream due to a sizeable body of research indicating that this
food protects against both cancer and cardiovascular disease.
Another fruit—one widely considered to be a
vegetable—has been the subject of intensive research for several
years, and has particularly interested the urological community,
myself included: the tomato. Studies of populations in various
countries have demonstrated that diets rich in tomatoes appreciably
reduce the risk of cancer of the prostate. Lycopene, a nutrient that
belongs to the same class as beta-carotene, appears to be the most
potently anti-carcinogenic, heart-protective compound in tomatoes.
Pomegranate: Powerful Antioxidants
Oxidation—where free radicals damage DNA, proteins
and fats in the body—is an important underlying factor in the
initiation of both cancer (particularly cancer of the prostate) and
heart disease. Chronic inflammation, where normal immune activity
against injury or infection becomes a sort of irritant in the body
instead of resolving, has also been strongly implicated as a causative
factor in both cancer and heart disease. Inflammation and oxidation
participate in a vicious cycle, each one amplifying the effects of the
other. Antioxidant protection is an essential part of reducing the ill
effects of chronic inflammation, and controlling inflammation will
reduce oxidative stress in the body.
My lab’s research into the anti-inflammatory
supplement Zyflamend
(New Chapter) has demonstrated that inflammation is a particularly
important factor in the development and progression of prostatic
intraepithelial neoplasia (PIN), a pre-cancerous prostate condition.
Research has firmly established the antioxidant and
anti-inflammatory effects of pomegranate. Additionally, pomegranate
juice has been found to have apoptotic effects in lab studies, which
means that it encourages the death of cancerous cells.
In the year 2000, Israeli researchers published a
series of studies that demonstrated anti-atherosclerotic (heart
disease-fighting) effects of pomegranate. They found that pomegranate
juice reduced “bad” LDL cholesterol and increased “good” HDL by 20
percent, with the oxidation of LDL reduced by up to 90 percent. The
research was coordinated by Michael Aviram, the same scientist who
first demonstrated that red wine reduced the oxidation of cholesterol.
(Cholesterol oxidation, where free radicals attack and alter
cholesterol in the bloodstream, is believed to be an important factor
in the development of clogged arteries that cause heart attack and
occlusive stroke.)
In both humans and mice, the equivalent of 8.3
ounces per day of pomegranate juice decreased the thickness of artery
walls and reduced the size of plaques. Further studies by Dr. Aviram’s
group found that pomegranate juice lowered systolic blood pressure
measurements in hypertensive patients in only a two-week period. Most
importantly, human subjects with cardiovascular diseases had many
subjective improvements and reduced symptoms, leading to improved
quality of life.
Many more studies have been performed at research
centers all over the world to back up Dr. Aviram’s results. Currently,
it is believed that the tannins and polyphenols (especially two called
punicalagin and ellagic acid) in pomegranate are responsible for its
anti-atherosclerotic effects.
In October of 2005, a study of pomegranate juice for
prevention and treatment of prostate cancer was published in the
Proceedings of the National Academy of Sciences. Investigators from
the University of Wisconsin Medical School performed the experiment on
a strain of mice that had been “infected” with human prostate cancer
cells. They found that giving the mice pomegranate juice caused their
tumors to shrink and their PSA (prostate specific antigen, measured in
the blood to detect prostate growth and prostate cancer) levels to
fall significantly.
Some recent studies show special promise for the
application of pomegranate juice in prostate cancer prevention—both
primary prevention and prevention of recurrence after a first bout
with the disease—and in slowing the progression of PIN to full-blown
prostate cancer. In a previous study by Allan J. Pantuck, M.D., an
assistant professor of urology at UCLA, 48 men who had been treated
for prostate cancer with either surgery or radiation were given
pomegranate juice in the months following. Their PSAs were checked
every three months. The juice intervention significantly increased the
length of time it took for PSAs to double.
At Columbia, we are currently participating in a
nationwide trial of POM Wonderful pomegranate juice for men who have
had prostate cancer recurrences, defined by increases in PSA
measurements. The study will be looking to duplicate Dr. Pantuck’s
results in a much larger group of patients, with a placebo group for
comparison.
Many of the natural chemopreventive compounds that
protect prostate health also show promise in protecting female
health—specifically, for prevention of breast cancer and
postmenopausal osteoporosis. Pomegranate contains abundant
phytoestrogens, compounds that mimic estrogens in the body, but that
do not have the growth-promoting (cancer-accelerating) effects of the
body’s natural estrogens or estrogen-replacing drugs. Phytoestrogens
in the diet are well-established as helpful prostate cancer
chemoprevention agents, and for the protection they offer against
breast cancer and weakening bones.
 Although
our arm of the multicenter pomegranate study isn’t yet completed, I
recommend pomegranate with confidence. It’s a no-risk,
multiple-benefit equation. If you choose a supplement over juice, keep
in mind that the research shows conclusively that the whole food is
more effective in every aspect than any of its isolated components. So
far, POM Wonderful appears to be an excellent choice if you prefer
juice.
Lycopene and Related Compounds: Lessons in Cancer
Prevention
Mediterranean nations have lower risk of heart
disease and cancers of the prostate, colon and breast than most other
nations. One reason the Mediterranean diet is believed to be so
strongly health-promoting is its abundance of tomatoes (and the fact
that they are usually cooked in oil, which aids in the bioavailability
of the lycopene they contain). Lycopene is a powerful antioxidant that
reduces LDL oxidation. Several large-scale population studies have
found reduced heart disease risk in people who consume more lycopene.
Past research has demonstrated that the higher a
woman’s blood plasma levels of lycopene, the lower her risk of
cardiovascular disease. Several other studies back this heart health-lycopene
level connection, including the famous Kuopio Ischaemic Heart Disease
Risk Factor Study, performed in Finland. Lycopene is strongly
protective against LDL oxidation.
Lycopene research is at a fever pitch in the
urological research community because it has been found to
significantly slow the growth of prostate cancer cells. At the
University of Illinois at Chicago, researchers gave pasta with tomato
sauce to men with prostate cancer for three weeks before their
prostatectomy (surgery to remove the prostate). They tracked the
subjects’ lycopene levels, blood DNA oxidation, and markers of
prostate cancer progression throughout. Subjects’ blood lycopene
levels doubled, and concentration of lycopene tripled in their
prostates. DNA oxidation fell—most notably, in the prostate—as did PSA.
Apoptosis of prostate cancer cells rose significantly in the subjects.
All in all, lycopene proved itself to be a remarkable ally against
prostate cancer growth in this study. And a small European study found
that men with PIN who were supplemented with lycopene had a much lower
conversion rate to prostate cancer.
Studies show that this nutrient may also help to
promote women’s health by helping to prevent breast, ovarian and
cervical cancers.
Including Foods Rich in Lycopene in Your Diet
 Eat
plenty of tomatoes. Enjoy them raw if you like them that way, but keep
in mind that their lycopene is most bioavailable when cooked with oil.
Some research suggests that olive oil has a synergy with tomatoes that
other oils don’t have. Use a high-quality extra-virgin olive oil if
possible, to reap the benefits of the unique polyphenolic antioxidants
those oils contain.
Add pomegranate to your diet as whole fruit or
juice. Watermelon is another good source of lycopene.
LycoPom, a whole-food supplement created by New Chapter, gives
you the nutritional equivalent of seven ounces of tomato and 15 whole
pomegranates (!!) per capsule. They add a variety of lesser-known
sources of lycopene, including rose hips and saffron, and antioxidant
herbs like rosemary, turmeric and coffeeberry. New Chapter includes as
many of the food’s naturally occurring synergistic nutrients as
possible in their supplements—and the research shows clearly that this
is a much more safe and efficacious approach than using single,
isolated nutrients. They use organically grown whole fruit and ensure
consistent, broad-spectrum content of the compounds known to promote
better health.
LycoPom is safe and useful for anyone who wants to be
proactive about prostate or breast cancer prevention, or who is
concerned about heart disease. One to two capsules a day are
recommended by New Chapter.
Resources
For more information on LycoPom click here.
References
Albrecht M, et al, “Pomegranate extracts potently
suppress proliferation, xenograft growth, and invasion of human
prostate cancer cells,” J Med Food 2004 Fall;7(3):274-83.
Aviram M, et al, “Pomegranate juice consumption for 3 years by
patients with coronary artery stenosis reduces common carotid intima-media
thickness, blood pressure and LDL oxidation,” Clin Nutr 2004
Jun;23(3):423-33.
Kim ND, et al, “Chemopreventive and adjuvant therapeutic potential of
pomegranate (Punica granatum) for human breast cancer,” Breast Cancer
Res Treat 2002 Feb;71(3):203-17.
Levi F, et al, “Dietary intake of selected micronutrients and
breast-cancer risk,” International Journal of Cancer 2001;91:260-3.
Levy J, et al, “Lycopene is more potent inhibitor of human cancer cell
proliferation than either A-carotene or beta-carotene,” Nutr Cancer
1995;24:257-266.
Malik A, et al, “Pomegranate fruit juice for chemoprevention and
chemotherapy of prostate cancer,” PNAS USA 2005 Oct
11;102(41):14813-8.
Sanjiv A, Rao AV, “Tomato lycopene and its role in human health and
chronic diseases,” Canadian Medical Association Journal
2000;163:739-744.
Seeram NP, et al, “In vitro antiproliferative, apoptotic and
antioxidant activities of punicalagin, ellagic acid and a total
pomegranate tannin extract are enhanced in combination with other
polyphenols as found in pomegranate juice,” J Nutr Biochem2005
Jun;16(6):360-7.
Sesso HD, et al, “Plasma lycopene, other carotenoids, and retinol and
the risk of cardiovascular disease in women,” Am J Clin Nutr 2004
Jan;79(1):47-53.
Stacewicz-Sapuntzakis M, Bowen PE, “Role of lycopene and tomato
products in prostate health,” Biochim Biophys Acta 2005 May
30;1740(2):202-5.
Sumner MD, et al, “Effects of pomegranate juice consumption on
myocardial perfusion in patients with coronary heart disease,” Am J
Cardiology 2005 Sep 15;96(6):810-4.
The statements contained on these pages have not
been evaluated by the Food and Drug Administration. The information
contained here is not intended to diagnose, treat, cure, or prevent
any disease. Suggestions and ideas presented in this document are for
information only and should not be interpreted as medical advice,
meant for diagnosing illness, or for prescriptive purposes. Readers
are encouraged to consult their health care provider before beginning
any cleanse, diet, detoxification program, or any supplement regimen.
The information in this article is not to be used to replace the
services or instructions of a physician or qualified health care
practitioner.
|
