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Q: hot flashes ( Answered,   0 Comments )
Subject: hot flashes
Category: Health > Women's Health
Asked by: mary55-ga
List Price: $5.00
Posted: 23 Sep 2006 22:14 PDT
Expires: 23 Oct 2006 22:14 PDT
Question ID: 767927
I've heard that contrary to the norm, some menopausal women experience
MORE hot flashes when they increase their intake of foods containing
phytoestrogens, such as soy.  Can you provide any statistics that
support that?
Subject: Re: hot flashes
Answered By: crabcakes-ga on 25 Sep 2006 20:30 PDT
Hello Mary55,

Yes, it seems the Mayo Clinic has done studies and found that
phytoestrogens either produce a slight amount of releif from hot
flases, or none, in breast cancer survivors.

   "Despite optimistic hopes that this soy phytoestrogen product would
alleviate hot flashes, the scientific data from this study
demonstrated that it did not help," said Charles Loprinzi, MD, a Mayo
Clinic medical oncologist and one of the authors of the study. "Thus,
we need to explore other means for alleviating hot flashes in women
who choose not to use estrogen or progesterone preparations."

   Susan Quella, principal investigator of the study and nurse
coordinator for the NCCTG, said the study originated after seeing
numerous advertisements that include claims about the benefits of soy,
without any science behind the assertions."

 "Although some women find that adding isoflavones to their daily diet
helps control hot flashes, clinical trials have yielded unimpressive
results. In general, researchers have observed only a modest decrease,
if any, in hot flashes for women who regularly consume soy products or
isoflavone supplements.

Because of the estrogen-like behavior of isoflavones, there's some
concern that isoflavone supplements increase cancer risk. If you've
had breast cancer, talk to your doctor before supplementing your diet
with isoflavone pills or red clover. Experts generally consider whole
foods containing soy or isoflavones to be safe when consumed in

    Tufts University also did a study, but says the jury is still out
on the final result. "Soy has been touted as a natural alternative
treatment to estrogen replacement therapy for women who suffer from
hot flashes during menopause. In a trial at Tufts University, this did
not prove true. Margo Woods, D.Sc., a Tufts researcher, studied the
action of isoflavones, estrogen-like compounds in soy, taken in a
supplement form by women suffering from daily hot flashes. She
reported that after three months, both the women taking a soy
supplement, and the women taking a placebo (dummy) pill, felt relief
from their hot flashes, thus negating a link to soy as the beneficial
ingredient. Since the jury is still out on soy?s ability to relieve
menopausal symptoms, experts suggest that women who choose soy
supplements for hot flashes should limit their intake to no more than
50 to 100 milligrams of isoflavones per day."

"Our incomplete understanding of hot flashes is reflected not only by
the lack of consensus over how common they are, but also by the
multitude of theories to explain what causes them. The most widely
accepted theory is that hot flashes are caused by a deficiency in
circulating estrogen as a result of declining ovarian function. We
know that fluctuating estrogen levels are at least part of the
picture, because many women experience relief from hot flashes while
taking estrogen.

This theory, however, does not fully explain the phenomenon of hot
flashes, as many menopausal and post-menopausal women with low
estrogen levels never experience hot flashes, while other women
simultaneously experience hot flashes and symptoms of a relative
estrogen excess. Signs of estrogen excess or estrogen dominance
include weight gain, breast tenderness, heavy menstrual flow, and
erratic mood swings. Furthermore, studies consistently show a 30%
improvement in hot flashes in women who are treated only with
placebos. We can infer from the response to placebo that hot flashes
are a complex neuroendrocrine phenomenon affected by a variety of
factors including our thoughts, expectations, and emotions. The wide
range of stimuli that trigger flushing further attests to the
multi-factorial nature of hot flashes. Common triggers include: spicy
food, hot drinks, alcohol, sugar, caffeine, stress, hot weather, hot
tubs and saunas, tobacco, and "heated" emotions. Be sure to read Power
Surge's Menopause Survival Tips."

"Italian researchers who studied 51 menopausal women found that those
who took daily supplements of 60 grams of soy protein had 45 percent
fewer hot flashes. But here's the rub: About half complained of
constipation or other gastroinestinal problems.

Researchers continue to study the relationship between a soy-rich diet
and female hormones. In the meantime, eating more soy can't hurt, and
might help with some of the discomforts endured by 60 percent of women
in the West."

   "This led the scientists to the theory that efficacy increased with
hot flash frequency, so that those women having around 10 hot flashes
each day saw this frequency halved, while those experiencing only
seven daily only saw a reduction of around three flashes, after taking

The researchers write that although conclusions based on the analysis
should be considered tentative, ?the available data justify the
recommendation that patients with frequent hot flushes consider trying
soyfoods or isoflavone supplements for the alleviation of their

They add that future trials involving soyfoods and isoflavone
supplements are warranted, "but should focus on women who have
frequent hot flashes". The correlation between initial hot flash
frequency and the extent of reduction of symptoms should also be
studied, they said.

"Finally it would be interesting to determine whether isoflavones are
more effective at preventing the onset of hot flashes when consumed
before menopause (rather than alleviating them once they have already
begun), " concluded the team."

I found no articles claiming that pytoestrogens caused an increase in
hot flashes; just that phytoestrogens did not help all women. Unless
studies take into account age, age of menopause, health of
participants, whether the woman took oral contraceptives, etc., it's
hard to compare how soy affects every woman.

If this is not the answer you were seeking, please request an Answer
Clarification, and allow  me to respond, before you rate this answer.

Regards, Crabcakes

Search Terms
increase in hot flashes + phytoestrogens
soy increases hot flashes
hot flashes + phytoestrogens or soy or isoflavones
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