Estrogen is a hormone that promotes sexual and reproductive development.
While present in both men and women of all ages, it’s usually found at much higher levels in women of reproductive age.
Estrogen carries out a range of functions in the female body, including regulating the menstrual cycle and growth and development of breasts (
However, during menopause women’s estrogen levels decline, which can lead to symptoms like hot flashes and night sweats.
Phytoestrogens, also known as dietary estrogen, are naturally occurring plant compounds that may act in a way similar to that of estrogen produced by the human body.
Here are 11 significant sources of dietary estrogens.
Phytoestrogens have a similar chemical structure to that of estrogen and may mimic its hormonal actions.
Phytoestrogens attach to estrogen receptors in your cells, potentially affecting the function of estrogen throughout your body (
However, not all phytoestrogens function in the same way.
Phytoestrogens have been shown to have both estrogenic and antiestrogenic effects. This means that, while some phytoestrogens have estrogen-like effects and increase estrogen levels in your body, others block its effects and decrease estrogen levels (
Because of their complex actions, phytoestrogens are one of the most controversial topics in nutrition and health.
While some researchers have raised concerns that a high intake of phytoestrogens may cause hormonal imbalance, most evidence has linked them to positive health effects.
In fact, multiple studies have associated phytoestrogen intake with decreased cholesterol levels, improved menopausal symptoms, and a lower risk of osteoporosis and certain types of cancer, including breast cancer (
Summary Phytoestrogens may have either estrogenic or antiestrogenic effects. The majority of research links phytoestrogens to a variety of health benefits.
Flax seeds are small, golden or brown-colored seeds that have recently gained traction due to their potential health benefits.
Summary Flax seeds are a rich source of lignans, chemical compounds that function as phytoestrogens. Eating flax seeds has been associated with a decreased risk of breast cancer.
Soybeans are processed into many plant-based products, such as tofu and tempeh. They can also be enjoyed whole as edamame.
Edamame beans are green, immature soybeans often sold frozen and unshelled in their inedible pods.
They are also rich in phytoestrogens known as isoflavones (
Soy isoflavones can produce estrogen-like activity in the body by mimicking the effects of natural estrogen. They may increase or decrease blood estrogen levels (
One study found that women who took a soy protein supplement for 12 weeks experienced moderate decreases in blood estrogen levels compared with a control group.
The researchers proposed that these effects might help protect against certain types of breast cancer (
The effect of soy isoflavones on human estrogen levels is complex. Ultimately, more research is needed before conclusions can be made.
Summary Soybeans and edamame are rich in isoflavones, a type of phytoestrogen. Soy isoflavones may affect blood estrogen levels in your body, although more research is needed.
Dried fruits are nutrient-rich, delicious, and easy to enjoy as a no-fuss snack.
They are also a potent source of various phytoestrogens (
Dates, prunes, and dried apricots are a few of the dried food sources highest in phytoestrogens (
What’s more, dried fruits are chock full of fiber and other important nutrients, making them a healthy snack.
Summary Dried fruits are a potent source of phytoestrogens. Dried apricots, dates, and prunes are some of the dried fruits with the highest phytoestrogen content.
Sesame seeds are small, fiber-packed seeds that are commonly incorporated into Asian dishes to add a delicate crunch and nutty flavor.
They are also quite rich in phytoestrogens, among other important nutrients.
Interestingly, one study found that the consumption of sesame seed powder may affect estrogen levels in postmenopausal women (
The women in this study consumed 50 grams of sesame seed powder daily for 5 weeks. This not only increased estrogen activity but also improved blood cholesterol (
Summary Sesame seeds are a potent source of phytoestrogens. Regularly eating sesame seeds has been shown to increase estrogen activity in postmenopausal women.
Garlic is a popular ingredient that adds a pungent flavor and aroma to dishes.
It’s not only touted for its culinary attributes but also renowned for its health properties.
Additionally, a month-long study involving postmenopausal women demonstrated that garlic oil supplements may offer protective effects against bone loss related to estrogen deficiency, though more research is needed (
Summary Along with its distinctive taste and health benefits, garlic is rich in phytoestrogens and may help reduce bone loss related to estrogen deficiency. However, more research in humans is needed.
Peaches are a sweet fruit with yellowish-white flesh and fuzzy skin.
They’re not only packed with vitamins and minerals but also rich in phytoestrogens known as lignans (
Interestingly, an analysis of studies suggests that lignan-rich diets may decrease the risk of breast cancer by 15% in postmenopausal women. This is possibly related to lignans’ effects on estrogen production and blood levels, as well as their expression the body (
Summary Peaches are sweet, delicious, and packed with a variety of nutrients. They are rich in lignans, a type of phytoestrogen.
Berries have long been touted for their numerous impressive health benefits.
They are loaded with vitamins, minerals, fiber, and beneficial plant compounds, including phytoestrogens.
Summary Some berries are rich in phytoestrogens, especially strawberries, cranberries, and raspberries.
However, these results were likely due to the high-fiber content of wheat bran and not necessarily its lignan content (
Ultimately, more research is needed to fully understand wheat bran’s effect on circulating estrogen levels in humans.
Summary Wheat bran is rich in phytoestrogens and fiber, which may decrease estrogen levels. However, more research is needed.
Tofu is made from coagulated soy milk pressed into firm white blocks. It’s a popular source of plant-based protein, especially in vegan and vegetarian diets.
It’s also a concentrated source of phytoestrogens, largely isoflavones.
Tofu has the highest isoflavone content of all soy products, including soy-based formulas and soy drinks (
Summary Tofu is made from soy milk condensed into solid white blocks. It’s a rich source of isoflavones, a type of phytoestrogen.
Cruciferous vegetables are a large group of plants with diverse flavors, textures, and nutrients.
Cauliflower and broccoli are rich in secoisolariciresinol, a type of lignan phytoestrogen (
Summary Cruciferous vegetables are rich in phytoestrogens, including lignans and coumestrol.
Tempeh is a fermented soy product and popular vegetarian meat replacement.
It’s made from soybeans that have been fermented and compacted into a firm, dense cake.
Tempeh is not only an excellent source of protein, prebiotics, vitamins, and minerals but also a rich source of phytoestrogens, especially isoflavones (33).
Summary Tempeh is a common vegetarian meat replacement made of fermented soybeans. Like other soy products, tempeh is rich in isoflavones.
The health benefits of consuming phytoestrogen-rich foods likely outweigh the potential risks, so these foods can be consumed safely in moderation.
However, limited research has suggested that there may be some risks and complications associated with a high intake of phytoestrogens. These findings are mixed and inconclusive, so more research is needed in humans.
Thus, strong conclusions about the dangers of phytoestrogens should be approached with skepticism.
Potential concerns people have raised about phytoestrogens include the following:
- Infertility. While some research states phytoestrogens may harm reproductive health, the bulk of this research has been conducted on animal models, and strong human studies are lacking (
34, 35, 36).
- Breast cancer. Limited research links phytoestrogens to an increased risk of breast cancer. Yet, some studies have observed the opposite — that high phytoestrogen intake may be linked to a decreased risk (
- Effects on male reproductive hormones. Contrary to popular belief, studies have shown that phytoestrogen intake has no effect on male sex hormones in humans (
- Decreased thyroid function. Some research associates intake of soy isoflavones with decreased thyroid hormone production. However, most studies in healthy adults have found no significant effects (
39, 40, 41).
While there is weak evidence from animal studies to suggest phytoestrogens may be linked to these complications, many human studies have not found evidence of this.
Additionally, many studies have associated phytoestrogen intake with potential health benefits, including lower cholesterol levels, improved menopause symptoms, and a decreased risk of osteoporosis and breast cancer (
Summary Some animal studies have identified potential health risks associated with phytoestrogen intake, but strong human research is lacking. Conversely, many studies have linked phytoestrogen intake to multiple health benefits and protective effects.
Phytoestrogens are found in a wide variety of plant foods.
To boost your phytoestrogen intake, try incorporating some of the nutritious and delicious foods listed in this article into your diet.
In most instances, the benefits of including these phytoestrogen-rich foods in your diet outweigh any potential health risks.