A decline in the female hormone estrogen is natural with increasing age and during certain phases of a woman’s reproductive cycle.[1] This hormonal change can often cause a plethora of uncomfortable symptoms and may come with specific health risks (especially in post-menopausal women).[1] Hormone replacement therapy is a common solution to ease symptoms of menopause and to lower health risks, such as osteoporosis that is associated with a drastic drop in estrogen levels. The issue with hormone replacement therapy is topical and oral consumption of phytoestrogen-containing foods has gained interest as a natural alternative to traditional hormone replacement therapy.[ that it is not suitable for every individual and also comes with its own risks (ovarian, uterine, and breast cancer) especially if taken for long periods of time.[2] This is one reason why 2] An added benefit of harnessing the power of phytoestrogens is that it may significantly improve the overall health and beauty of skin by reducing signs of aging.
First Things First: What Is Estrogen?
Although estrogen is commonly known as a reproductive hormone that is more abundant in females (produced in the ovaries) and fluctuates with the menstrual cycle, estrogen is also normally produced by males in low amounts in other tissues.[3] Estrogen production in both males[3] and females reduces significantly with age, which can increase the risk of[4]
- Heart disease
- Osteoporosis (without estrogen, the breakdown of bone is not monitored and this can lead to low bone mineral density)
- Menopausal symptoms in women (i.e. hot flashes)
In relation to skin health, declining levels of estrogen (as seen in menopausal women) can cause increased dryness, wrinkling, and photoaging.[1] One of the proposed health benefits of phytoestrogens on skin health includes its protective and antioxidant activities, and its ability to modulate estrogen levels.[3,5]
The Breakdown of Phytoestrogens
Phytoestrogens are natural estrogen compounds in certain plant-based foods that are very similar in structure to the hormone estrogen. They are typically found in plant and have the ability to bind to estrogen receptors throughout the body and balance estrogen levels. A few of the more commonly known groups of phytoestrogens found in dietary sources include:[4]
- Polyphenols (i.e. resveratrol, lignans) found in grape skin, red wine, flaxseeds
- Catechins found in green tea, chocolate, berries
- Isoflavones (i.e. genistein, daidzein) found in soybeans and other legumes
- Flavonols (i.e. quercetin, kaempferol) found in apples, kale, broccoli
- Coumestans (i.e. coumestrol) found in clover, alfalfa, spinach
How Do Phytoestrogens Affect Skin Health?
There are two different types of estrogen receptors throughout the body:Â [4,6,7]
- alpha-estrogen receptors
- beta-estrogen receptors
The two receptors are found in various tissues in different concentrations throughout the body. It has been found that the dominant type of estrogen receptors found in skin tissue are beta-estrogen receptors, and phytoestrogens have an affinity for binding to beta-estrogen receptors.[4]
According to this article, beta-estrogen receptors are thought to be involved with skin photoaging, wound healing, and skin tumor growth.[7] Although more research is needed to understand exactly how different phytoestrogens may benefit skin health, the list below includes a few of the skin benefits found from various studies (including both animal and human studies). This is by no means a comprehensive list and includes either topical application or oral intake of various phytoestrogens.
Top Phytoestrogen-Containing Foods:[8]
- Soy
- Tempeh
- Flaxseeds
- Oats
- Lentils
- Yams
- Apples
- Red clover
- Hops (flowers from the hop plant Humulus lupulus)
- Sesame seeds
- Wheat germ
Three Ways Your Skin Could Benefit from Phytoestrogens
1)Â Â Â Improved Skin Elasticity
- Soy isoflavones may stimulate elastin production and give the skin a better ability to “bounce back”[6,7]
- Oral intake and topical application[7,9]
2)Â Â Â Increased Thickness of Skin
- Topical application of racemic equol can stimulate collagen synthesis thereby increasing the thickness of the skin[1,6,10]
3)Â Â Â Reduced Wrinkle Depth
- Oral intake of soy isoflavone may reduce fine wrinkles[7]
- UV protection in photoaging[1,6,7]
- Topical application of racemic equol and resveratrol[7]
Possible Health Risks of Phytoestrogen Intake
Although phytoestrogens may benefit individuals with either very high or very low estrogen levels, its dietary consumption and topical use are controversial. This controversy is due to its possibility to cause hormone-related health change. Some of the controversies have centered on the possible risk for infertility and cancer with a high soy-based intake but this has not been proven with research studies.[4] It is thought that these hormone-related health risks may be increased if phytoestrogen intake was higher earlier on in life (before reaching puberty), or before birth.[4]
We May Have Different Abilities to Metabolize Phytonutrients
It is also important to consider the overall diet, lifestyle, and other factors when weighing the pros and cons of consuming phytoestrogens such as soy. For instance, the benefits of isoflavones may vary among individuals depending on their gut microflora.[10] This article looked at different bacteria strains in the colon that are responsible for breaking down the soy isoflavone called daidzin.[10] Daidzin is metabolized into daidzein and further broken down into equol.[10] Equol is more readily absorbable across the intestines and binds more easily to the estrogen receptors.[2,3,10] The interesting point that comes across with this study is that it is estimated that approximately 30% of the Western population is able to metabolize daidzein into equol (whereas others can only breakdown daidzin into daidzein).[10] On the other hand, it is thought that about 60% of the Asian population has the ability to produce equol.[10]
Weighing the Risks and Benefits of Phytoestrogens
The overall effect of including phytoestrogens in your diet depends on your age, hormonal health, sex, health status, gut flora, and daily diet.[4] Other lifestyle factors can also improve health status such as exercise, water intake, fiber intake, etc. As always, it is best to seek the care of a professional medical provider when making the decision to incorporate phytoestrogens into your diet and/or utilize it topically.
