Are Phytoestrogens the Same as Oestrogen?

An acknowledged international expert  in female hormones is naturopath Lara Briden. She has written extensively about hormone health and you will find very helpful articles on hormone health on her website.

I value her work and would like to share her thoughts on a common misconception: the difference between oestrogen and phytoestrogens.

What are they?

Phytoestrogens are a group of natural nutrients found in almost all plant foods. The two main types are isoflavones, which are found in soy, and lignans, which are present in seeds, whole grains, legumes, fruits, and vegetables.

They are called phytoestrogens because they interact with oestrogen receptors, but they are not the same as oestrogen. In fact, they attach to these receptors very weakly, which means they can block estradiol, making them better described as anti-oestrogen.

What effect can they have?

It’s been known for a long time that crops with isoflavones, like red clover, reduce the oestrogen and fertility of farm animals, and it’s even been suggested that plants developed phytoestrogens to lower the fertility of female plant-eating animals and stop them from eating too much.

In a chapter titled “Agriculture and Selection for High Levels of Estrogen,” evolutionary biologist Grazyna Jasienska argues that early humans adjusted to farming and eating plant foods high in phytoestrogens by increasing their own natural oestrogen levels.

So, people with ancestors who farmed are likely “hormonally adjusted” to eating a lot of plant-based phytoestrogens from food to protect us from our own high oestrogen.

How might they affect you?

So, what does this mean for hormonal health? Well, for one thing, it’s fine to eat plant-based oestrogens like beans and seeds. They have been a part of our regular diet for a long time, and our body’s hormones can handle them.

How they affect women’s hormones

During the reproductive years, when oestrogen is high, phytoestrogens have a beneficial effect and can help to promote the healthy metabolism or detoxification of oestrogen.

Hormone-sensitive cancer. Prevention may even be helped by food-based phytoestrogens.

Heavy periods. By reducing oestrogen, phytoestrogens generally make periods lighter. However, if the dose is high enough to suppress ovulation and progesterone (the hormone that lightens periods), the result can be a heavier period.

Endometriosis. In general, phytoestrogens should be neutral for endometriosis, or even slightly beneficial. Some women with endometriosis report a worsening of symptoms with soy which is probably due to an immune reaction.

PCOS. Phytoestrogens can improve insulin resistance and have been found to have a beneficial effect on the hormonal condition polycystic ovary syndrome.

Hypothalamic amenorrhea. Phytoestrogens cannot correct the oestrogen deficiency of hypothalamic amenorrhea. The treatment for hypothalamic amenorrhea is to promote ovulation by eating more. Read my blog post about oestrogen deficiency.

Menopause. During menopause, when oestrogen is low, phytoestrogens can have a mild pro-oestrogen effect. That has led to a great deal of research into the use of phytoestrogen supplements such as soy as an alternative to menopausal hormone therapy.

From hundreds of studies and a few meta-analyses, it appears that isoflavones may help hot flushes, but don’t do much, if anything, for other hormonal symptoms of menopause.

Thyroid disease. Concentrated extracts of soy isoflavones may suppress thyroid function. Food-based soy is probably okay as long as you also have enough iodine.

In conclusion

Phytoestrogens generally have a beneficial anti-oestrogen effect in women.

They have a mild pro-oestrogen effect in menopausal women, which may be beneficial, and a pro-oestrogen effect in men and children, which may be detrimental at a high dose.

Helpful information: 

Oestrogen has had a bad press, but it is an essential hormone for women. The problem arises when it is in excess and when not balanced by progesterone, the hormone designed to balance it.

This can lead to a condition known as oestrogen dominance, which was first identified by the late Dr John Lee who was the pioneer in the use of bioidentical progesterone for women.

Women who have a history of breast cancer risk for example generally can’t have oestrogen, but phytoestrogens are generally accepted.

Wellsprings Serenity cream and Menopause Capsules provide help with hormonal symptoms such as hot flushes and sweats, sleep and tiredness for women who cannot have oestrogen itself.

Women with more severe symptoms who can have a little oestrogen can use Twenty to One which has the majority ingredient of progesterone and two natural oestrogens derived from soy.

Women have often been concerned about oestrogen and whether it is suitable for them to use. It can certainly depend on whether you have been strictly forbidden to use it by your Doctor but there are a number of occasions when women with a hormonal history or risk for cancer may be able to do so.

Dr Tony Coope is an experienced expert in women’s hormonal health and has written the following article which you may find helpful if you have further questions.

Bioidentical Hormones & Cancer