Phytoestrogens - the good, bad and ugly

Phytoestrogens are plant-based estrogens that naturally occur in many common foods like soy, almonds, sesame seeds, apples and carrots. They have many health benefits - however, recent scientific studies show that at high levels, they can mess with our body’s estrogen levels, thereby affecting the menstrual cycle and fertility.

Here’s everything you need to know.

What is phytoestrogen?

Phytoestrogen is exactly what its name suggests - estrogen found in plants. They are similar to estrogen found in our bodies, but not exactly identical. As a result, they may not bind to our body’s estrogen sensors (or “receptors”) as firmly.

How do phytoestrogens work inside my body?

Phytoestrogens imitate estrogen because their chemical structure is very similar to that of estrogen from the body.

When phytoestrogens enter the body, the body’s estrogen receptors treat them as if they were estrogen. Phytoestrogens are called “endocrine disruptors” because they are chemicals that disrupt normal hormonal function.

However, phytoestrogens do not bind to estrogen receptors as firmly as estrogen produced by the body, so their effects may be weaker.

Can phytoestrogens impact my fertility?

Animal and human studies indicate that phytoestrogens can suppress the production of ovulation hormones such as FSH (Follicle Stimulating Hormone) and LH (Leutenizing Hormone), lowering fertility, especially in women of Asian descent. The possible negative effects of phytoestrogens seem to be restricted to women of the reproductive age group, who have active hormonal cycles.

All of these studies involved high levels of soy isoflavones (these are different compounds present in soy, not related to soy proteins) or soy supplements in the diet, so including soy as part of a regular balanced diet should still be okay.

Can consuming phytoestrogens earlier in life impact my cycle today?

One study of women who were fed soy formula as infants found that this group had somewhat longer and more painful periods than people who were fed cow's milk formula. Another study of infants who were fed soy formula found slight differences in the sizes of their uteruses at 6 months of age, compared to those fed cow’s milk formula, suggesting estrogen exposure.

Though these studies indicate some effects due to soy based products, they still do not conclude that soy is harmful, as long as it is consumed in moderation.

Are they all bad?

No, not at all! Once a woman is past her active reproductive age and entering menopause, her natural estrogen levels gradually fall. At this stage of life, eating foods rich in phytoestrogen can be beneficial in controlling symptoms of menopause. They may help reduce hot flashes, reduce risk of breast cancer, maintain bone health and promote heart health.

Consumption of phytoestrogen has also been linked to reduced endometriosis related inflammation, in this one study here, although this is still far from conclusive proof. They are also likely to reduce acne, according to this study from 2017, although the study is still inconclusive.

So what should I do?

While there have been several studies connecting soy and other phytoestrogen rich foods with fertility issues in women, these foods offer multiple other benefits when eaten in moderation as part of a balanced diet. So, soy isoflavone supplements and foods made with textured vegetable protein (such as soy chunks, tempeh etc.) as well as soy based protein powders and nutrition bars. Still, it's okay to eat whole soy foods — like soy milk, edamame, and tofu — in moderation, up to several times per week.

If all of this is confusing, that’s completely natural. New studies come up everyday connecting diet, lifestyle and menstrual health. It can be hard to keep track of it all and give your body the best.

An easy way to manage your menstrual wellness is to simply download the Femcy app. Our experts take advantage of the latest science to offer personalized recommendations for your diet, fitness and mental wellness, for a better menstrual cycle.

So what are you waiting for? Download the Femcy app now!

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Nandhini heads marketing for FemCy. She is a health science enthusiast and believes that knowledge is key to making better selfcare decisions.

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