Phytoestrogens and Nutritional Support
Phytoestrogens are natural compounds found in some plants. They exert estrogen-like activity in the body and may be an effective alternative to bioidentical HRT for some women.
Some of the best evidence to support the use of phytoestrogens comes from Asia, where women do not typically experience many of the diseases and menopausal symptoms associated with the loss of estrogen. One explanation for this may be the phytoestrogens found in soy and other plant products consumed in Asian diets (Aso 2010; Cho 2010; Sarkar 2003).
Phytoestrogens bind to estrogen receptors and help modulate estrogen activity (Zittermann 2003). When estrogen levels are too low, their very mild estrogenic effect raises total estrogenic activity. Alternatively, when estrogen levels are too high, they compete with estrogen at cellular receptor sites, thus reducing endogenous estrogenic impact. By competing with endogenous estrogen for estrogen receptors, phytoestrogens may help prevent the growth and spread of several hormone-dependent cancers (Adlercreutz 1992). They have also been shown to decrease the risk of some degenerative diseases including cardiovascular disease, osteoporosis, breast and uterine cancer (Baber 2010; Bawa 2010; Cho 2010; Messina 2008; Miyake 2009).
Dietary and supplemental phytoestrogens present a way for women to obtain limited hormonal support without the use of hormone therapy.
Cardiovascular Benefits: Unlike conventional HRT, which has been shown to raise the risk of heart attack among postmenopausal women, phytoestrogens have a positive effect on the heart. In 1999 the United States Food and Drug Administration authorized the use of health claims on food labels that link increased soy consumption with a reduced risk of coronary artery disease (Vincent 2000). One study of more than 400 women demonstrated that phytoestrogens, through their effect on the arterial walls (particularly in older women), protect against arterial degeneration and atherosclerosis (van der Schouw 2002).
A scientific review of studies on phytoestrogens found they offer the following cardiovascular benefits:
- Improvements in lipid disturbances as a result of activating beneficial estrogen receptor sub-types (Okamura 2008)
- Decreased blood pressure, LDL cholesterol, total cholesterol, and triglycerides (De Kleijn 2002)
- Increased HDL cholesterol and improved cardiovascular profile (Bairey Merz 2006; De Kleijn 2002)
- Lowering the overall rate of cardiovascular disease among people with higher consumption of phytoestrogens (Ariyo 2002)
- Lowering of lipids in people with high cholesterol via genistein and daidzein, two of the most extensively studied phytoestrogens (Teede 2001; Zittermann 2003)
- Reduction in the risk of atherosclerosis due to increased levels of daidzein and genistein, which inhibit LDL oxidation (Exner 2001)
In addition, a six-month study of more than 180 women confirmed that a soy-rich diet is as effective as conventional HRT for lowering lipid levels (Park 2005).
Furthermore, phytoestrogens have almost 3 times the radical scavenging activity as vitamins C and E, as well as help protect arterial walls (Ruiz-Larrea 2000; van der Schouw 2002).
Brain protection: Estrogen and estrogen-like compounds protect brain cells from degenerative changes due to aging and oxidative stress (Bhavnani 2003; Linford 2002).
- The phytoestrogen genistein protects animal subjects from the effects of brain ischemia, the kind of injury seen in stroke (Schreihofer 2009; Donzelli 2010; Ma 2010).
- Genistein has anti-apoptotic activity, protecting cultured brain cells from self-destructing over time (Yu 2009).
Osteoporosis and bone health: Studies have shown that postmenopausal women with a habitually high intake of phytoestrogens have high bone mineral density of the spine and hip (Bawa 2010; Hanna 2004). A number of studies have been conducted on phytoestrogens and bone health, and their conclusions are as follows:
- Genistein and daidzein increase bone mineralization (Taku 2010; Clifton-Bligh 2001; Kanno 2004).
- Genistein and daidzein decrease bone resorption and inflammatory factors while increasing osteogenic (bone-forming) proteins (Ma 2008; Jia 2003; Rassi 2002; Yamaguchi 2000; Zhang 2004).
- An isoflavone mixture of daidzein and genistein demonstrated significant increases in bone mineral density after six months of treatment. Women who ingested 57mg daily of isoflavones had a 4% increase in bone mineral density (Clifton-Bligh 2001).
- A phytoestrogen preparation containing daidzein and genistein demonstrated protective effects on the lumbar spine (Atkinson 2004).
- Dietary supplementation with 54mg daily of genistein “may be as effective as hormone replacement therapy in attenuating menopause-related bone loss without causing the associated side effects” (Cotter 2003).
Cancer Protection: Studies demonstrate a significantly lower incidence of sex hormone-related cancer in Asian countries (Sarkar 2003; Vij 2004). These studies, which attribute this result to the traditionally high intake of soy isoflavones in the Asian diet, have concluded the following:
- Daily soy isoflavone consumption is associated with decreased breast cancer risk (Lu 2001). A diet containing 113–202 mg daily (depending on body size) of genistein and daidzein can increase the production of the protective 2-hydroxylated estrogen, decrease estradiol and its harmful metabolites, and lower the long-term risk of breast cancer (Lu 2000).
- Genistein and daidzein have an inhibitory effect on uterine cancer (Lian 2001).
- Genistein intake is linked with lower rates of stomach cancer (Ko 2010).
Menopause symptoms: Several studies have demonstrated that natural estrogen significantly decreases hot flashes and vaginal atrophy (Albert 2002; Chiechi 2003). Treatment with 54mg daily of genistein safely decreased hot flashes up to 30% and should be considered as an alternative treatment for postmenopausal conditions (Crisafulli 2004). Subsequent studies showed a decrease in hot flushes of more than 56% (D'Anna 2009). Another study concluded that “genistein can be used for the management of hot flushes in postmenopausal women not treated with hormone replacement therapy due to their superior efficacy to placebo and very good safety profile” (Ferrari 2009).
Additional Natural Ingredients to Target the Symptoms of Menopause
Black cohosh. Black cohosh has been used in the treatment of climacteric symptoms such as hot flashes, mood disturbances, diaphoresis, palpitations, and vaginal dryness (Donnelly 2007; Oktem 2007; Shams 2010). Additionally, black cohosh conveys antiproliferative effects on breast cancer cells (Fang 2010; Al-Akoum 2007; Hostanska 2004). Data suggests it is comparable to some pharmaceutical prescription medications for preventing bone loss (Nisslein 2003).
Dong quai. Dong quai, based on its use in Chinese medicine for gynecological disorders (i.e., painful menstruation or pelvic pain, recovery from childbirth or illness, and fatigue/low vitality), is referred to as “female ginseng” (Goh 2001; Hardy 2000). It is an effective remedy for alleviating menopausal symptoms without proliferative changes in the uterus or vagina (Hirata 1997). A study demonstrated that a preparation of soy isoflavones, black cohosh, and dong quai reduced menstruation-related migraine headaches (Burke 2002).
Licorice root. Licorice root exerts estrogen-like effects and has been shown to reduce body fat, positively impact testosterone metabolism (Hu 2009; Armanini 2002; Josephs 2001), and decrease serotonin reuptake by up to 60% which may help alleviate menopausal depression (Ofir 2003). Licorice root also assists with repair of blood vessel walls and supports arterial health, thus reducing the risk of cardiovascular disease (Somjen 2004).
Vitex agnus-castus. Extracts from the fruit and leaves of vitex agnus-castus (vitex), also known as chasteberry, contain chemicals with diverse beneficial effects for the treatment of premenstrual symptoms (Dante 2010). In one study, menopausal women reported excellent symptomatic relief after using two essential oils from vitex (Chopin 2003).
Nutrients to Complement Bioidentical HRT
Vitamin D. Vitamin D confers significant protective effects against breast cancer. In a study, women with higher vitamin D levels had a nearly 70% reduction in their risk of breast cancer compared to women with the lowest levels (Abbas 2008). Laboratory studies have shown that vitamin D suppresses growth of breast cancer by:
- blocking signals that stimulate cancer cell growth
- enhancing signals that inhibit cancer cell growth
- favorably altering genetic regulators of the cell cycle (Ben-Shoshan 2007; Lee 2007; Jamshidi 2008; Crew 2009)
Vitamin D helps prevent mutated cells from becoming malignant and even induces cancer cell death (apoptosis). Human studies show that doses of 1100 IU vitamin D daily plus calcium result in a 60% risk reduction for developing any cancer, compared with placebo (Lappe 2007).
Cruciferous Vegetables. Cruciferous vegetables such as broccoli, cauliflower, cabbage, kale, and Brussels sprouts can help detoxify dangerous estrogen breakdown products that promote cancer growth (Lampe 2009; Ambrosone 2004). When estrogens are metabolized via certain biochemical pathways, they become more likely to trigger cancer (Fowke 2000; Muti 2002). Aging adults suffer from a high prevalence of cancers associated with an imbalance in estrogen metabolism (Fowke 2000; Muti 2002). Cruciferous vegetables contain compounds that promote a healthier pathway for the breakdown of estrogens in the body, thus protecting against cancer (Muti 2000; Michnovicz 1997; Michnovicz 1998; Kall 1997; Bradlow 1996; Dalessandri 2004).
A chief component of cruciferous vegetables, indole-3-carbinol (I3C), prevents the conversion of estrogen to its breast cancer promoting 16-alpha-hydroxyestrone form, while increasing conversion to its cancer-fighting 2-hydroxyestrone form (Acharya 2010; Weng 2008; Muti 2000).
Lignans. Lignans can slow the growth of breast cancer in women. Thirty-two women awaiting surgery for breast cancer were randomized to receive a muffin either with or without (control group) 25 grams of flaxseeds. Analysis of the cancerous tissue after surgery revealed that markers of tumor growth were reduced by 30%-71% in the flaxseed group, with no change noted in the control group (Thompson 2005).
A recently published study found that a combination of lignans, I3C, and calcium-d-glucarate along with other supportive herbs favorably altered the 2/16-hydroxyestrone ratio in pre- and post-menopausal women. The researchers remarked, “Supplementation with a mixture of indole-3-carbinol and… lignan in women significantly increased estrogen C-2 hydroxylation. This may constitute a mechanism for the reduction of breast cancer risk as well as risk for other estrogen-related cancers” (Laidlaw 2010).
A comprehensive review of 21 studies found that postmenopausal women with higher lignan intake were significantly less likely to get breast cancer. The investigators concluded that “high lignan exposure may be associated with a reduced breast cancer risk in postmenopausal women” (Buck 2010).
Fish oil. Fish oil, with its high omega-3 fatty acid content, reduces cancer risk by a number of mechanisms. Fish oil reduces oxidative stress and suppresses production of many inflammatory mediators that contribute to cancer development (Kansal 2010). It can sensitize tumor cells to chemotherapy effects (even when metastases are present), potentially reducing the doses of chemotherapy required for treatment (Bougnoux 2009).
A study revealed that fish oil, through its effect on oxidative stress and induction of apoptosis, can prevent the progression of colon cancer (Sarotra 2010). In an animal model of breast cancer, fish oil supplementation was shown to reduce bone metastasis by blunting the expression of a protein called CD44, which drives cancer cell migration (Mandal 2010).
Green tea. Green tea polyphenols, particularly one called epigallocatechin gallate (EGCG), suppress the growth and reproduction of human breast cancer cells. They have reduced the number of breast cancer tumors in animal models of the disease (Thangapazham 2007a; Thangapazham 2007b; Leong 2008). Green tea also reduces the production of vascular endothelial growth factor (VEGF), helping to starve tumors of their blood supply while down-regulating cancer-promoting estrogen receptors and increasing apoptosis (Leong 2008; Masuda 2002; Farabegoli 2007; Hsuuw 2007).
Pomegranate. Pomegranate has been extensively studied for its antioxidant properties as well as its cancer-fighting capacity. With respect to breast cancer, pomegranate is an especially promising phyto agent due to its ability to both inhibit the cancer-promoting enzyme aromatase and suppress angiogenesis, which is the process by which tumors gain new blood vessels (Toi 2003; Sturgeon 2010).
Equine estrogens and synthetic progestins remained the staple of menopausal care until 2002, when the Women’s Health Initiative (WHI) revealed the dangers associated with these unnatural hormone replacement methods. As women learned that conventional hormone replacement therapy was closely tied to an increased risk of certain cancers, many abandoned their trust in mainstream medicine and turned to natural bioidentical hormones as well as scientifically-validated phytoestrogens for menopausal symptom relief.
Emerging science continues to undermine conventional hormone replacement therapy in favor of bioidentical hormone replacement. Studies confirming the estrogen receptor modulating abilities of the natural estrogen estriol provide reassurance for women who seek relief from the ravages of age-related hormone loss without the fear of increased cancer risk.
By coupling healthy diet and lifestyle habits with regular blood testing and bioidentical hormone replacement therapy, women today have a means to look and feel their best at any age.
Given the preponderance of evidence, women should feel confident that bioidentical hormone replacement, when appropriately prescribed, offers a safer and potentially more effective alternative to conventional HRT to help relieve menopausal symptoms and optimize long-term health. The addition of several proven nutrients to a bioidentical hormone regimen may help optimize estrogen metabolism and reduce cancer risk even further, offering an optimal, balanced approach to health maintenance.