Phytoestrogens

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Phytoestrogens

• Skip Wyss, Corey Roth, Leah Bonde,
• Tessa Gryglewski, Carrie Mashl
• Jaclyn Katers,

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Menopause

• Begins in your late 40s and early 50s
• Decrease in steroid production in the ovaries
• Decrease in Estrodial, (Esrtone)
• Increase in Androgens, (androstenedione)

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Symptoms of Menopause

• Hot Flashes
• Night Sweats
• Vaginal Dryness
• Loss of Libido
• Urinary symptoms

• Skin Changes
• Difficulty with intercourse
• Irritability
• Anxiety

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Treatment of Menopause

• Estrogen Replacement Therapy (ERT)
• thought to cause cancer
• Replaced by Phytoestrogens
• Taken in through diet.
• Better form of estrogen therapy

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What are Phytoestrogens?

• chemicals found in plants that act similar to the
  female hormone estrogen
• but are much weaker than estrogen

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What are Cont...

• 2 Main Types of Phytoestrogens
• Lignans
• believed to reduce the risk of certain cancers,
  like breast cancer
• Isoflavones
• known for their effects on estrogen metabolism
  and female health

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Sources of Phytoestrogens

• found in many common plants
• soybeans and soy products
• soymilk and tofu are the richest
• red clover (richest in Isoflavones)
• flaxseed
• lentils and many beans
• sunflower and sesame seeds
• green and yellow vegetables (to some extent)

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What Do They Do

• Phytoestrogens have estrogenic and
  anti-estrogenic activities in humans.
• They are structurally similar to mammalian
  estrogen, estradiol, and have estrogenic
  properties. However, their estrogenic activity
  is generally much less than that of human
  estrogens.
• Phytoestrogens are seen to show a positive
  correlation with Asian women who eat a lot of
  them, and a lowered incidence of menopausal
  symptoms within the Asian population.

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What Do They Do

• Phytoestrogens have about 1/500 to 1/1000 the
  activity of estradiol.
• Therefore, phytoestrogens can act as anti-
  estrogenic effects by blocking the estrogen
  receptors and exerting weaker estrogenic effects.
• It is very important to appreciate that
  estrogenic compounds such as phytoestrogens can
  be agonistic or antagonistic to estradiol.
• Most Studies done as of present are to review the
  effects of phytoestrogens in place of HRT.

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Phytoestrogen Effects

• Studies are not conclusive at this time but show
  that eating a lot of soy, which contains
  phytoestrogens can lead to
• Moderately less bone loss
• Lower total and LDL cholesterol
• Slightly relieve the symptoms of menopause, but
  far less effectively than estrogen.
• Lowered risks of cancers such as breast, ovarian,
  and prostate.

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Phytoestrogens and Cancers

• Optimistic Findings
• Incidence of hormone associated cancer is much
  higher in industrialized western societies when
  compared to Asian populations (believed to be
  linked with consumption of soy)
• Study found significant reduction in
  breast-cancer risk among women with high intakes
  of some forms of phytoestrogens
• Study found that women with breast cancer had
  generally lower levels of phytoestrogen in urine
  than healthy women
• Increased consumption of fruits and vegetables
  containing phytoestrogens have been linked to the
  reduction of breast cancer
• 4-5 servings lowers risk by 46 instead of only 2
  servings

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Phytoestrogens and Cancers Cont

• Negative Findings
• Factors beside soy intake may contribute to Asian
  populations having a low cancer rate, while
  Western populations have a significantly greater
  rate of cancer, such as low fat diets
• Study found that the some phytoestrogens
  stimulated growth of estrogen-dependent breast
  cancer cell lines
• Some studies show soy has a week protective
  affect in regards to cancers
• Animal studies show dietary soy may promote tumor
  growth

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Phytoestrogens and Cancers Cont

• Xenoestrogens (environmental oestrogens)
• related to an increased rate of cancer
• Related to an increase of breast tumors in women
• Sources
• Chlorinated hydrocarbons
• DDT
• PCBs
• Contraceptive pill

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Phytoestrogens and Cancers Cont

• Inconclusive Evidence
• What can be generalized from the findings of
  these studies are inconclusive
• Cannot determine which is the cause and which is
  the effect
• Increased vegetable products at expense of animal
  fat may lead to decreased susceptibility to
  cancer
• Do not know if taking soy and alfalfa concentrate
  supplements work

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Effects of Phytoestrogens on Cholesterol

• Two types of Cholesterol
• HDLGood
• take LDL out of the blood back to the liver
• LDLbad
• can oxidize causing a build up of plaques and
  eventually lead to Cardiovascular Disease

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Effects on Cholesterol Cont..

• Due the decrease in Estrogen, the stored
  cholesterol will be released into the blood
  stream, thus causing an increase of LDL.
• Testosterone has the same effect in men. This is
  why Cardiovascular Disease in most common in men
  until women hit menopause, then they will even
  out.

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Effects on Cholesterol Cont..

• Soya products reduce the LDL cholesterol
• this will help out the HDL in reuptake
• this must happen in order to ensure open/clear
  arteries and a healthy heart

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Effects on Osteoporosis

• means porous bone
• this is a result of the thinning of the bones
• Decrease in Estrogen will cause an decrease in
  osteoblast production.
• Increase in osteoclasts
• Stimulate break down of bony matrix.
• Increase in Parathyroid Hormone (PTH)
• Phytoestrogens add a form of estrogen back into
  the blood stream.
• Stimulation of Blast,
• Inhibition of Clast PTH

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Toxicity of Phytoestrogens

• Have potential mutagenic, carcinogenic and
  teratogenic properties
• Phytoestrogen absorption and metabolism must be
  taken into affect to account for their safety and
  efficacy
• Recent study states that phytoestrogens can cause
  harm in animals and is being researched for
  potential damage to infants using Soya products
• They have been shown to induce infertility in
  certain animals
• Possible increase in colon and stomach cancer,
  depending on exposure and duration of product

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Soya Products

• Soya is found in foods such as soya sauces, miso,
  and tempeh
• These are considered safe to eat because of long
  fermentation process
• Soya is the second most common allergen in the US
• Can also be found in certain breakfast cereals,
  ice cream, convenience foods (hamburgers, fish),
  baked goods, tortillas, etc.
• Some claim the importance of only eating
  organically processed foods whenever possible

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Soya Products Cont.

• Contains high quantities of toxic chemicals that
  are not rendered down by the long cooking process
• Block the bodys uptake of minerals, hinder
  protein ingestion, inhibits oxygen take up and
  growth
• Women should be warned not to feed their babies
  soya products, there is a two fold increase of
  developing thyroid abnormalities, retarded
  physical maturation and early onset of puberty
  for girls

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Sources used

• http//www.findarticles.com/cf_dls/m0813/1_27/5921
  0038/p1/article.jhtml
• http//www.cancernet.co.uk/phytoestrogens.htm
• http//breastcancer.about.com/cs/soy/index.htm
• http//herbsforhealth.about.com/library/weekly/aa0
  22799.htm
• Bauer, Class Notes, Biology of Women, 2004