Lignans
and breast
cancer
Fruits,
meats,
and colon
cancer
Flavonoids
lower heart
deaths
Second
hand smoke
risks
Alcohol,
aneurysm,
and breast
cancer
Meat
protein
and endometrial
cancer
Ask
Dr. J: Ipriflavone
and hormones
Lignans
are estrogen-like
compounds
found in
plant foods
such as seeds,
nuts, fruits,
vegetables,
whole grains,
and beans.
Lignans (plant-based
estrogens)
from non-soy
sources are
far more
common in
the Western
diet than
those from
soy foods.
Flax and
sesame seeds
contain the
far more
lignans than
most other
good sources.
Flax seeds
contain 85
mg per ounce,
and sesame
seeds contain
11 mg per
ounce, while
other food
sources contain
less than
1 mg per
serving.
A study
from France,
published
in the Journal
of the National
Cancer Institute,
shows that
post-menopausal
women who
consume large
amounts of
lignans have
a lower risk
of breast
cancer. Risk
reduction
was 17 percent
for women
with the
highest lignan
intake (greater
than 1.4
mg per day)
compared
to those
with the
lowest intake.
(Touillaud
MS, et al.,
Dietary lignan
intake and
postmenopausal
breast cancer
risk by estrogen
and progesterone
receptor
status. J
Natl Cancer
Inst. 2007
Mar 21;99(6):475-86.)
This study
involved
58,049 post-menopausal
women followed
for an average
of 7.7 years.
Over that
time there
were a total
of 1469 cases
of diagnosed
breast cancer.
Earlier studies
were unclear
on the relationship
of lignans
to breast
cancer, but
in this study,
they are
clearly helpful
in this age
group.
After flax
and sesame
seeds, the
best sources
of lignans
are brassica
family foods
(kale, broccoli,
and cabbage),
apricots,
strawberries,
and whole
grains. These
lignan-rich
foods are
also high
in fiber,
vitamins,
minerals,
antioxidants,
and other
phyto-chemicals
that protect
against heart
disease and
other cancers.
Polyps in
the colon
are benign
growths that
have a tendency
to lead to
malignancies.
Larger polyps
are more
likely to
harbor malignant
cells. A
new study
shows that
a diet high
in fruit
and low in
meat appears
to protect
against the
development
of colorectal
polyps and
cancers.
In this study,
vegetables
or moderate
reduction
of meat in
the diet
did not appear
to offer
the same
protection
as the high-fruit,
very-low-meat
combination.
Other studies
have also
shown an
association
of meat eating
with colon
cancer.
Researchers
at the University
of North
Carolina
evaluated
725 patients
who had just
had colonoscopies.
Those who
ate large
or moderate
amounts of
meat had
a 70 percent
greater risk
of having
polyps found
during the
examination,
compared
to those
who ate a
lot of fruit
and very
little meat.
(Austin GL,
et al., A
diet high
in fruits
and low in
meats reduces
the risk
of colorectal
adenomas.
J Nutr. 2007
Apr;137(4):999-1004.
Flavonoids
are plant
pigments
that have
antioxidant
activity
and other
healthful
properties,
including
reducing
both LDL
cholesterol
levels and
inflammation.
A wide variety
of these
phytochemicals
(also called
bioflavonoids)
is found
in many plant
foods. The
Iowa Women’s
Health Study
reports that
women who
had the highest
intake of
flavonoids
had a lower
risk of death
from heart
disease and
a lower incidence
of heart
and blood
vessel diseases.
The study
evaluated
34,489 women
over 16 years
and specifically
looked at
intake of
three kinds
of flavonoids – anthocyanins,
flavones,
and flavanones.
Specific
foods that
were helpful
included
bran from
whole grains,
apples, red
wine, pears,
strawberries,
and grapefruit.
(Mink PJ,
et al., Flavonoid
intake and
cardiovascular
disease mortality:
a prospective
study in
postmenopausal
women. Am
J Clin Nutr.
2007 Mar;85(3):895-909.)
Risk reduction
ranged from
10 to 22
percent.
Although
this may
seem small,
reducing
heart deaths
by this amount
could prevent
50 to 100,000
deaths per
year in the
United States.
Also, adding
many small
benefits
through health
habit changes
gives you
much greater
control of
your health
future.
While I
am skeptical
of the value
of many meta-analysis
studies (a
review of
other studies)
they are
useful on
the occasions
when they
provide confirmation
of the weight
of other
evidence
or new insights.
A meta-analysis
of the dangers
of second-hand
smoke (environmental
smoke) shows
that non-smokers
exposed to
such smoke
have a 24
percent increase
in lung cancer
risk.
Long-term
exposure
(30 years)
led to a
50 percent
increase,
and those
considered
to be heavily
exposed to
the smoke
of others
(restaurant
and bar workers)
have a 100
percent greater
risk of developing
lung cancer
than non-smokers.
Researchers
evaluated
studies from
many countries
(Stayner
L, et al.,
Lung cancer
risk and
workplace
exposure
to environmental
tobacco smoke.
Am J Public
Health. 2007
Mar;97(3):545-51.)
Passive exposure
to tobacco
smoke is
also associated
with asthma
and other
respiratory
ailments.
The wall
of the aorta
where it
passes through
the abdomen
is sometimes
weakened
and bulges
out to form
an aneurysm.
This is usually
the result
of atherosclerosis,
and leads
to a life-threatening
risk of rupture.
A new study
shows that
moderate
alcohol consumption
(two drinks
a day) is
associated
with an increased
risk of developing
such aneurysms.
(Wong DR,
et al., Smoking,
hypertension,
alcohol consumption,
and risk
of abdominal
aortic aneurysm
in men. Am
J Epidemiol.
2007 Apr
1;165(7):838-45.)
This Harvard
study of
39,352 men
for 16 years
showed that
the aortic
aneurysm
risk was
21 percent
higher when
considering
alcohol use
at the start
of the study.
When evaluation
of alcohol
consumption
was updated
every four
years, the
risk was
61 percent
higher than
for non-drinkers.
Another
Harvard study
shows that
as little
as one drink
per day increases
a woman’s
risk of invasive
breast cancer
by 9 percent,
while two
drinks per
day (other
than red
wine) increases
the risk
by 43 percent.
(Zhang SM,
Alcohol consumption
and breast
cancer risk
in the Women's
Health Study.
Am J Epidemiol.
2007 Mar
15;165(6):667-76.)
This is data
from the
Women’s
Health Study
of 38,454
subjects
followed
for an average
of 10 years.
The evidence
for the value
of reducing
or eliminating
meat from
the diet
is pretty
clear by
now, and
it keeps
accumulating.
A study from
Shanghai,
China showed
that the
women who
consumed
the most
protein from
animal sources
had double
the risk
of endometrial
cancer as
women who
consumed
the least
animal protein.
High levels
of animal
fat in the
diet boosted
the risk
by 50 percent.
High total
calorie intake
was also
associated
with greater
risk. (Xu
WH, et al.,
Nutritional
factors in
relation
to endometrial
cancer: a
report from
a population-based
case-control
study in
Shanghai,
China. Int
J Cancer.
2007 Apr
15;120(8):1776-81.)
On the other
hand, women
who consumed
most of their
protein from
vegetable
sources cut
their risk
by 30 percent.
The study
compared
1204 women
with newly
diagnosed
endometrial
cancer with
1212 healthy
women. Saturated
fat was related
to increased
risk, but
no association
was found
with polyunsaturated
fats. The
researchers
also found
that vitamins
A, C, and
E, as well
as fiber
and beta-carotene
all reduced
the risk,
whether they
were derived
from food
or supplements.
Q: I have
been told
to take ipriflavone
to improve
my bone density,
but I am
concerned
about risks.
Will I need
to take progesterone
to protect
against uterine
cancer?
L.B. California,
via email
A: Ipriflavone
is similar
to soy isoflavones
but has been
modified
to increase
its beneficial
effect on
bone. Depending
on the studies
you look
at it appears
to help rebuild
bone or at
least to
halt the
progression
of bone loss.
However,
even though
it has some
similarities
to plant-derived
estrogens,
it does not
have estrogenic
effects in
the body.
I have seen
only one
side effect
reported,
which is
a lowered
white blood
cell count
in a few
patients.
Whether this
is clinically
significant
is not clear.
Natural
bio-identical
progesterone
(not the
synthetic
derivatives
that until
recently
have been
heavily prescribed)
is a very
safe hormonal
treatment.
Even if you
don’t
need it because
of the ipriflavone,
it may still
be worth
taking. In
itself it
helps to
maintain
bone density.
Therefore
it can work
quite well
with ipriflavone
to support
the bones.
