Soy Food Helps Women with Breast Cancer Decrease
Death Risk, Avoid Recurrence
Study including senior citizens suggests moderate soy food intake is safe and
potentially beneficial for women with breast cancer
Soybeans have
found their way into an eye-opening array of foods, according to
the Agricultural Research Service. Starting with the basics,
there's soy milk, Oriental staple tofu, soybean curd, soy
yogurt, soyburgers, soy loaf, and soy sausage. Soy oil is the
most widely used edible oil in the United States. Soy components
such as protein and oil are ingredients in dozens of everyday
foods-from granola bars to potato chips. You'll be hard put to
find a chocolate treat that lacks soy lecithin.
Thanks to ARS
research, soybeans have been incorporated into a host of nonfood
products - from newspapers printed with so oil-based ink to
lipstick, plastics. flooring, paints, and stain-removing
cleaners. Photo by Scott Bauer, ARS More below news
report.
Dec. 9, 2009 - Although there is a concern
regarding the safety of soy food consumption among breast cancer
survivors, researchers have found that women in China who had breast
cancer and a higher intake of soy food had an associated lower risk of
death and breast cancer recurrence, according to a study in the December
9 issue of the Journal of the American Medical Association (JAMA).
(Note: Read more about Soy
from MedlinePlus below this news report.)
"Soy foods are rich in isoflavones, a major group
of phytoestrogens that have been hypothesized to reduce the risk of
breast cancer. However, the estrogen-like effect of isoflavones and the
potential interaction between isoflavones and tamoxifen have led to
concern about soy food consumption among breast cancer patients," the
authors write in explaining why they pursued this study.
Xiao Ou Shu, M.D., Ph.D., of Vanderbilt University
Medical Center, Nashville, Tenn., and colleagues examined the
association between soy isoflavone intake with breast cancer recurrence
and survival.
The researchers analyzed data from the Shanghai
Breast Cancer Survival Study, a large, population-based study of 5,042
female breast cancer survivors in China. Women ages 20 to 75 years with
diagnoses of breast cancer between March 2002 and April 2006 were
recruited and followed up through June 2009.
Information on cancer diagnosis and treatment,
lifestyle exposures after cancer diagnosis, and disease progression was
collected at approximately 6 months after cancer diagnosis and was
reassessed at three follow-up interviews conducted at 18, 36, and 60
months after diagnosis. A Shanghai Vital Statistics Registry database
was used to obtain survival information for participants who were lost
to follow-up.
> After a median (midpoint) follow-up of 3.9 years,
444 total deaths and 534 recurrences or breast cancer-related deaths
were documented among the group of 5,033 surgically-treated breast
cancer patients.
> Soy food intake, as measured by either soy
protein or soy isoflavone intake, was inversely associated with
mortality and recurrence.
> Patients in the group with the highest intake of
soy protein had a 29 percent lower risk of death during the study
period, and a 32 percent lower risk of breast cancer recurrence compared
to patients with the lowest intake of soy protein.
> The adjusted 4-year mortality rates were 10.3
percent and 7.4 percent and the 4-year recurrence rates were 11.2
percent and 8.0 percent, respectively, for women with the lowest and
highest groups of soy protein intake.
"The inverse association was evident among women
with either estrogen receptor-positive or -negative breast cancer and
was present in both users and nonusers of tamoxifen," the researchers
write.
"In summary, in this population-based prospective
study, we found that soy food intake is safe and was associated with
lower mortality and recurrence among breast cancer patients.
”The association of soy food intake with mortality
and recurrence appears to follow a linear dose-response pattern until
soy food intake reached 11 grams/day of soy protein; no additional
benefits on mortality and recurrence were observed with higher intakes
of soy food. This study suggests that moderate soy food intake is safe
and potentially beneficial for women with breast cancer."
Editorial: Clinicians can advise patients with
breast cancer that soy foods are safe to eat and that these foods may
offer some protective benefit for long-term health
An editorial in JAMA says that while this study
provides important information, there are several concerns, including
differences in the quality, type and quantity of soy food intake between
China and the U.S. (47 mg/d vs. 1 to 6 mg/d, respectively, average
isoflavone intake).
Rachel Ballard-Barbash, M.D., M.P.H., of the
National Cancer Institute, Bethesda, Md., and Marian L. Neuhouser,
Ph.D., of the Fred Hutchinson Cancer Research Center, Seattle, also,
point out the relatively short median follow-up time of the study (4
years); that there likely are differences in screening rates in China
compared with the U.S.; and a number of factors may make it difficult to
compare stage- and treatment-specific results in China with outcomes in
the U.S.
"Even though the findings by Shu et al suggest that
consumption of soy foods among breast cancer patients is probably safe,
studies in larger cohorts are required to understand the effects of
these foods among diverse clinical subgroups of breast cancer patients
and survivors.
“In the meantime, clinicians can advise their
patients with breast cancer that soy foods are safe to eat and that
these foods may offer some protective benefit for long-term health.
“Moreover, the potential benefits are confined to
soy foods, and inferences should not be made about the risks or benefits
of soy-containing dietary supplements. Patients with breast cancer can
be assured that enjoying a soy latte or indulging in pad thai with tofu
causes no harm and, when consumed in plentiful amounts, may reduce risk
of disease recurrence."
All
About Soy From MedlinePlus
This information was obtained from MedlinePlus,
which brings together authoritative information from National Library of
Medicine, the National Institutes of Health, and other government
agencies and health-related organizations. (12/09/2009)
Soy is a subtropical plant, native to southeastern
Asia. This member of the pea family (Fabaceae) grows from one to
five-feet tall and forms clusters of three to five pods, each containing
two to four beans per pod. Soy has been a dietary staple in Asian
countries for at least 5,000 years, and during the Chou dynasty in China
(1134-246 B.C.), fermentation techniques were discovered that allowed
soy to be prepared in more easily digestible forms such as tempeh, miso,
and tamari soy sauce. Tofu was invented in 2nd-Century China.
Soy was introduced to Europe in the 1700s and to
the United States in the 1800s. Large-scale soybean cultivation began in
the United States during World War II. Currently, Midwestern U.S. states
produce approximately half of the world's supply of soybeans.
Soy contains protein, isoflavones, and fiber, all
thought to provide health benefits. Soy is an excellent source of
dietary protein, including all essential amino acids. Soy is also a
source of lecithin or phospholipid. Soy isoflavones and lecithin have
been studied scientifically for numerous health conditions. Isoflavones
such as genistein are believed to have estrogen-like effects in the
body, and as a result are sometimes called "phytoestrogens."
Common sources of soy isoflavones include roasted
soybean, green soybean, soy flour, tempeh, tofu, tofu yogurt, soy hot
dogs, miso, soy butter, soy nut butter, soy ice cream, soy milk, soy
yogurt, tofu pups®, soy cheese, bean curd, seitan, and soy noodles.
Soybean flour is found in Spanish sausage products (chorizo, salchichon,
mortadella, and boiled ham), doughnuts, and soup stock cubes. Although
processed soy foods (e.g., veggie burgers, tofu pups®, meatless dinner
entrees, chicken-free nuggets, soy "ice creams" and energy bars) are
usually high in protein, they typically contain lower levels of
isoflavones.
Soy protein has also been investigated for benefit
in terms of other cardiovascular disease risk factors, reducing
menopausal symptoms, weight loss, arthritis, brain function, and
exercise performance enhancement.
Dietary soy may decrease the risk of breast
cancer in women and prostate cancer in men, as well as other types of
cancers.
In general, the supportive evidence for use of
phytoestrogens as treatments for menopause, cardiovascular disease,
osteoporosis (weak bone mass), and cancer is limited. The use of soy
formula has been investigated in the treatment of diarrhea in infants
and is an effective and safe alternative to cow's milk formula in most
infants. Due to limited human study, there is currently not enough
evidence to recommend for or against the use of soy for weight
reduction.
These uses have been tested in humans or
animals. Safety and effectiveness have not always been proven. Some of
these conditions are potentially serious, and should be evaluated by a
qualified healthcare provider.
Soy products, such as tofu, are high in protein and are an
acceptable source of dietary protein.
A
High cholesterol
Numerous human studies report that adding soy protein to the
diet can moderately decrease blood levels of total
cholesterol and low-density lipoprotein ("bad" cholesterol).
Small reductions in triglycerides may also occur, while
high-density lipoprotein ("good" cholesterol) is altered in
some, but not all, studies. Some scientists have proposed
that specific components of soybean, such as the isoflavones
genistein and daidzein, may be responsible for the
cholesterol-lowering properties of soy. However, this has
not been clearly demonstrated in research and remains
controversial. It is not known if products containing
isolated soy isoflavones have the same effects as regular
dietary intake of soy protein. Dietary soy protein has not
been proven to affect long-term cardiovascular outcomes,
such as heart attack or stroke.
A
Diarrhea (acute) in infants
and young children
Numerous studies report that infants and young children
(2-36 months old) with diarrhea who are fed soy formulas
experience fewer daily bowel movements and fewer days of
diarrhea. This research suggests that soy has benefits over
other types of formula, including cow milk-based solutions.
The addition of soy fiber to soy formula may increase the
effectiveness. Better quality research is needed before a
strong recommendation can be made.Parents are advised to
speak with qualified healthcare providers if their infants
experience prolonged diarrhea, become dehydrated, develop
signs of infections (such as fever), or have blood in the
stool. A healthcare provider should be consulted for current
breastfeeding recommendations and to suggest long-term
formulas that provide enough nutrition.
B
Allergies (prevention of food
allergies)
Soy formulas are commonly used by infants with sensitivities
to milk-based formulas. There is currently little evidence
to support the use of soy formulas for preventing food
allergies. Further research is needed in this field.
C
Antioxidant
There is some evidence in support of soy increasing
antioxidant status in humans. In general, diets high in
plant foods may offer antioxidant benefits. Further research
is required in this field before recommendations can be
made.
C
Bowel/intestinal disorders
The effect of soy on erosive-ulcer lesions of the alimentary
tract has been examined in limited study. Overall, the
effects of soy products appear beneficial. Further study is
required before recommendations can be made.
C
Cancer (prevention and
treatment)
Several large population studies have asked people about
their eating habits and reported that higher soy intake
(such as dietary tofu) is associated with a decreased risk
of developing various types of cancers, including breast,
prostate, and colon cancer. However, other research suggests
that soy does not have this effect. Until better research is
available, it remains unclear if dietary soy or soy
isoflavone supplements increase or decrease the risk of
these cancers.
C
Cardiovascular disease
Dietary soy protein has not been shown to affect long-term
cardiovascular outcomes, such as heart attack or stroke.
Research does suggest cholesterol-lowering effects of
dietary soy, which in theory, may reduce the risk of heart
problems. Soy has also been studied for blood
pressure-lowering and blood sugar-reducing properties in
people with type 2 diabetes, although the evidence is not
definitive in these areas. In women with suspected cardiac
ischemia, high levels of the soy isoflavone genistein have
been associated with blood vessel problems. Further
investigation is needed before a strong recommendation can
be made.
C
Cognitive function
It is unclear if soy isoflavone supplementation in
postmenopausal women can improve cognitive function. Results
from studies are mixed.
C
Crohn's disease
Due to limited human research, there is not enough evidence
to recommend for or against the use of soy as a way to
prevent Crohn's disease. Further research is needed before a
recommendation can be made.
C
Cyclical breast pain
It has been theorized that the "phytoestrogens" (plant-based
compounds with weak estrogen-like properties) in soy may be
beneficial to premenopausal women with cyclical breast pain.
However, due to limited human research, there is not enough
evidence to recommend for or against the use of dietary soy
protein as a therapy for this condition.
C
Diabetes
Several small studies have examined the effects of soy
products on blood sugar levels in people with type 2
("adult-onset") diabetes. Results are mixed, with some
research reporting decreased blood glucose levels and other
trials noting no effects. Overall, research in this area is
not well designed or reported and better information is
needed.
C
Exercise performance
enhancement
Soy protein has been investigated as a source of protein
with potential for benefit in exercise performance. In
general, research findings suggest soy protein is better
than no protein but is unlikely to be superior to other
sources of protein. Further research is required in this
field.
C
Gallstones (cholelithiasis)
Due to limited human research, there is not enough evidence
to recommend for or against the use of soy as a therapy in
cholelithiasis. Further research is needed before a strong
recommendation can be made.
C
Gastrointestinal motility
In limited available studies, the addition of soy
polysaccharide to non-regular diets increased the moisture
content of stool and decreased the number of liquid stools.
It is not clear if soy polysaccharide would be superior to
other fiber sources in this regard.
C
High blood pressure
There is limited human research on the effects of dietary
soy on blood pressure. Some research suggests that
substituting soy nuts for non-soy protein may help improve
blood pressure. Further research is needed before a firm
recommendation can be made.
C
Infantile colic
There is currently a lack of scientific evidence to
recommend for or against the use of soy formula for
fussiness and gas in infants with cow's milk allergy over a
partially hydrolyzed cow's milk protein formula.
C
Inflammation
There is currently a lack of scientific evidence to
recommend for or against the use of soy protein on
inflammation associated with hemodialysis (removal of waste
products from the blood).
C
Iron deficiency anemia
There is currently a lack of sufficient evidence to
recommend for or against the use of soy-based formula in the
treatment of iron deficiency anemia in children.
Due to limited human study, there is not enough evidence to
recommend for or against the use of soy in the treatment of
kidney diseases, such as nephrotic syndrome. People with
kidney disease should speak with their healthcare providers
about the recommended amounts of dietary protein because soy
is a high-protein food.
C
Menopausal symptoms
Overall, evidence suggests that soy products containing
isoflavones may help reduce menopausal symptoms, such as hot
flashes. More study is needed to confirm this use.
C
Menstrual migraine
A phytoestrogen combination may help prevent menstrual
migraine attacks. Further research is needed before a strong
recommendation can be made.
C
Metabolic syndrome
Treatment with soy protein and soy nuts was evaluated in
patients with metabolic syndrome and benefits were found in
terms of plasma lipids in patients consuming soy nuts as
part of the DASH (Dietary Approaches to Stop Hypertension)
diet. Further research is required in this field in terms of
soy protein supplementation.
C
Obesity/weight reduction
Some research suggests that soy might be as effective as
skim milk and more effective than a low-calorie diet alone
in reducing weight. Other research has reported conflicting
results. Further research is needed before a strong
recommendation can be made.
C
Osteoarthritis
Osteoarthritis is a form of arthritis caused by the
breakdown of cartilage. Early research suggests that intake
of soy protein may be associated with reduced symptoms of
osteoarthritis.
C
Osteoporosis
It has been theorized that "phytoestrogens in soy" (such as
isoflavones) may increase bone mineral density in
post-menopausal women and reduce the risk of fractures.
However, more research is needed before a conclusion can be
made.
C
Quality of life
The effect of soy on quality of life has been investigated
in limited study. Further study is required before
recommendations can be made.
C
Rheumatoid arthritis
There is currently insufficient evidence to recommend for or
against the use of soy as a treatment for rheumatoid
arthritis.
C
Skin aging
It is unclear if aglycones, a form of soy isoflavone, can
improve aged skin in middle-aged women when it is taken by
mouth. More research is needed.
C
Skin damage caused by the sun
A soy moisturizing cream may help improve signs of sun
damage, including discoloration, blotchiness, dullness, fine
lines, and overall texture. Because the cream contained
other ingredients besides soy, more research with soy alone
is needed.
C
Spinal cord injury
Whey protein has traditionally been used as a protein source
to increase body strength. Limited available study
investigated whether soy protein could be used to increase
ambulation performance in patients with incomplete spinal
cord injury. There is currently not enough evidence to
recommend for or against the use of soy as a treatment for
increased endurance in individuals with spinal cord injury.
C
Thyroid disorders
Early research suggests that soy supplements do not affect
thyroid function. More research is needed.
C
Tuberculosis
It has been suggested that soy may be beneficial for
tuberculosis when taken with standard medications. According
to early research, soy may improve the process of
detoxification, have positive effects on the liver, reduce
cell damage, and decrease inflammation. Therefore, soy
supplements may allow patients to safely take higher doses
of antimicrobial drugs that are used to treat tuberculosis.
C
Weight gain (infants)
In limited study, weaning infants with cow's milk allergy to
soy based formula resulted in reduced weight for age as
compared with formulas containing hydrolyzed proteins
(broken down). Further research is required in this field.
C
*Key to grades
A: Strong scientific evidence for this use;
B: Good scientific evidence for this use;
C: Unclear scientific evidence for this use;
D: Fair scientific evidence against this use;
F: Strong scientific evidence against this use.
The below
uses are based on tradition or scientific theories. They often have not
been thoroughly tested in humans, and safety and effectiveness have not
always been proven. Some of these conditions are potentially serious,
and should be evaluated by a qualified healthcare provider.
The Food and Drug
Administration determined that diets with four daily soy
servings can reduce levels of low-density lipoproteins (LDLs),
the so-called "bad cholesterol" that builds up in blood vessels,
by as much as 10 percent.
Soy protein products can be
good substitutes for animal products because, unlike some other
beans, soy offers a "complete" protein profile. Soybeans contain
all the amino acids essential to human nutrition, which must be
supplied in the diet because they cannot be synthesized by the
human body. Soy protein products can replace animal-based
foods--which also have complete proteins but tend to contain
more fat, especially saturated fat--without requiring major
adjustments elsewhere in the diet.
From Soyfoods Assocation
According to the Soyfoods
Association, the Food and Drug Administration approved a health
claim for foods that contain at least 6.25 grams of soy. The
health claim states that, “25 grams of soy protein a day, as
part of a diet low in saturated fat and cholesterol, may reduce
the risk of heart disease.”
The
below doses are based on scientific research, publications, traditional
use, or expert opinion. Many herbs and supplements have not been
thoroughly tested, and safety and effectiveness may not be proven.
Brands may be made differently, with variable ingredients, even within
the same brand. The below doses may not apply to all products. You
should read product labels, and discuss doses with a qualified
healthcare provider before starting therapy.
Adults (over 18 years old)
Soy is typically consumed as a protein drink, soy flour, isolated soy
protein (e.g. Supro®), extract, fiber/cereal, or milk beverage. Studies
have examined the effects of 10-106 grams of soy with an isoflavone
content of about 40-120 milligrams taken daily for up to 12 months by
mouth.
A dose of 20-106 grams of soy protein taken daily by mouth has been
studied in people with high cholesterol. Isoflavone content has ranged
from 60 to over 100 milligrams daily. Cholesterol and low-density
lipoprotein levels have been reduced in people using these doses of soy
protein. There is limited study of soymilk (400 milliliters daily) in
pre-menopausal women, with reported benefits on cholesterol levels.
Additional doses have been studied but are not recommended due to a lack
of available scientific evidence.
Children (under 18 years old)
Due to potential safety concerns, a qualified healthcare provider should
be consulted regarding the choice of infant formula.
Safety
The
U.S. Food and Drug Administration does not strictly regulate herbs and
supplements. There is no guarantee of strength, purity or safety of
products, and effects may vary. You should always read product labels.
If you have a medical condition, or are taking other drugs, herbs, or
supplements, you should speak with a qualified healthcare provider
before starting a new therapy. Consult a healthcare provider immediately
if you experience side effects.
Allergies
Soy may act as a food allergen similar to milk, eggs, peanuts, fish, and
wheat. Symptoms of an allergic reaction range from a runny nose to a
sudden drop in blood pressure.
Side Effects and Warnings
Soy has been a dietary staple in many countries for more than 5,000
years and it does not appear to cause long-term toxicity. Aside from
allergic reactions, limited side effects have been reported in infants,
children, and adults.
Soy protein taken by mouth has been associated with stomach and
intestinal difficulties, such as bloating, nausea, and constipation.
Changes in stool quality have been reported. More serious intestinal
side effects have been uncommonly reported in infants fed soy protein
formula, including vomiting, diarrhea, growth failure, and
damage/bleeding of the intestine walls. People who experience intestinal
irritation (colitis) from cow's milk may also react to soy formula.
Based on human case reports and animal research, soy may affect thyroid
hormone levels in infants. There have been rare reports of goiters
(enlarged neck due to increased thyroid size). Hormone levels became
normal again after stopping soy. Infants fed soy or cow's milk formula
may also have higher rates of atopic eczema than infants who are
breastfed.
Acute migraine headache has been reported with the use of a soy
isoflavone product. Based on animal research, damage to the pancreas may
theoretically occur from regularly eating raw soybeans or soy
flour/protein powder made from raw, unroasted, or unfermented beans.
The use of soy is often discouraged in patients with hormone-sensitive
cancers, such as breast, ovarian, or uterine cancer, due to concerns
about possible estrogen-like effects (which theoretically may stimulate
tumor growth). Other hormone-sensitive conditions, such as
endometriosis, may also theoretically be worsened. In laboratory
studies, it is not clear if isoflavones stimulate or block the effects
of estrogen or both (acting as a "receptor agonist/antagonist"). Until
additional research is available, patients with these conditions should
be cautious and speak with a qualified healthcare practitioner before
starting use.
It is not known if soy or soy isoflavones share the same side effects as
estrogens, such as increased risk of blood clots. Early studies suggest
that soy isoflavones, unlike estrogens, do not cause the lining of the
uterus (endometrium) to build up.
There has been a case report of vitamin D deficiency rickets in an
infant nursed with soybean milk (not specifically designed for infants).
Patients should consult their qualified healthcare practitioners for
current breastfeeding recommendations and use formulas with adequate
nutritional value.
Pregnancy and Breastfeeding
Soy as a part of the regular diet is traditionally considered to be safe
during pregnancy and breastfeeding, although scientific research is
limited in these areas. The effects of high doses of soy or soy
isoflavones in humans are not clear, and therefore are not recommended.
Recent study demonstrates that isoflavones, which may have estrogen-like
properties, are transferred through breast milk from mothers to infants.
High doses of isoflavones given to pregnant animals have resulted in
tumors and reproductive changes in offspring, although this has not been
tested in humans.
In one human study, male infants born to women who ingested soymilk or
soy products during pregnancy experienced more frequent hypospadias (a
birth defect in which the urethral meatus, the opening from which urine
passes, is abnormally positioned on the underside of the penis).
However, other human and animal studies have examined males or females
fed soy formula as infants, and have not found abnormalities in infant
growth, head circumference, height, weight, occurrence of puberty,
menstruation, or reproductive ability.
Research in children during the first year of life has found that the
substitution of soy formula for cow's milk may be associated with
significantly lower bone mineral density. Parents considering the use of
soy formula should speak with qualified healthcare practitioners to make
sure the appropriate vitamins and minerals are provided in the formula.
Interactions
Most
herbs and supplements have not been thoroughly tested for interactions
with other herbs, supplements, drugs, or foods. The interactions listed
below are based on reports in scientific publications, laboratory
experiments, or traditional use. You should always read product labels.
If you have a medical condition, or are taking other drugs, herbs, or
supplements, you should speak with a qualified healthcare provider
before starting a new therapy.
Interactions with Drugs
Soy contains "phytoestrogens" (plant-based compounds with weak
estrogen-like properties), such as isoflavones. It is not clear if
isoflavones stimulate or block the effects of estrogen or both (acting
as a "receptor agonist/antagonist"). It is not known if taking soy or
soy isoflavone supplements increases or decreases the effects of
estrogen on the body, such as the risk of blood clots. It is unclear if
taking soy alters the effectiveness of birth control pills containing
estrogen.
It is not known what the effects of soy phytoestrogens are on the
anti-tumor effects of selective estrogen receptor modulators (SERMs)
such as tamoxifen. The effects of aromatase inhibitors such as
anastrozole (Arimidex®), exemestane (Aromasin®), or letrozole (Femara®)
may be reduced. Because of the potential estrogen-like properties of
soy, people receiving these drugs should speak with their oncologists
before taking soy in amounts greater than normally found in the diet.
Soy protein may interact with warfarin (Coumadin®), although this
potential interaction is not well characterized. Patients taking
warfarin should check with a doctor and pharmacist before taking soy
supplementation.
Genistein, a major component of soy, may alter the way some drugs are
broken down in the liver.
Soy may also potentially interact with agents taken for diabetes,
diarrhea, high blood pressure, high cholesterol, obesity, or
cardiovascular disorders. In theory, various types of soy may interact
with antibiotics, diuretics (water pills), iron salts,
immunosuppressants or thyroid hormones. Conclusive human data is lacking
for these interactions. Patients are advised to check with a qualified
healthcare professional, including a pharmacist.
Interactions with Herbs and
Dietary Supplements
The effects of soy protein or flour on iron absorption are not clear.
Studies in the 1980s reported decreases in iron absorption, although
more recent research has noted no effects or increased iron absorption
in people taking soy. People using iron supplements as well as soy
products should consult their qualified healthcare practitioners to
follow blood iron levels. Calcium and phosphate levels may be altered.
Some experts believe that there may be a potential interaction between
soy extract and Panax ginseng , although this possible
interaction is not well understood.
Prebiotics (complex sugars) do not appear to affect how the body absorbs
soy. It is unclear if probiotics (commonly found in cultured milk
products like yogurt) affect the absorption of soy.
Soy may also potentially interact with herbs or supplements taken for
cancer, diabetes, diarrhea, high blood pressure, high cholesterol,
obesity, or cardiovascular disorders. In theory, various types of soy
may interact with antibacterials, antioxidants, blood thinners,
diuretics (water pills), immunomodulators, phytoestrogens, or thyroid
hormones. Conclusive human data is lacking for these interactions.
Patients are advised to check with a qualified healthcare professional,
including a pharmacist.
Soy has been studied along with various foods, herbs and supplements,
such as avocado, beta-sitosterol, black cohosh, branched chain amino
acids, green tea, lecithin, lycopene, magnesium, magnolia bark extract,
oats, seaweed, spirulina, and tomatoes. There is not enough scientific
evidence to make a firm conclusion about the effects when taken
together.
Theoretically, soy protein may inhibit phosphate and calcium absorption
and increase the absorption of manganese. Soy may also lower zinc and
selenium levels in the blood. Soy nuts may be able to reduce sugar
levels in the blood, but the magnitude of this effect is unclear.
Genistein, a major component of soy, may alter the way some herbs and
supplements are broken down in the liver.
Keep up with the latest news for senior citizens, baby
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All
About Soy From MedlinePlus