Oestrogens — not just for women!

Jun 13, 2024

Date:13 June 2024

Content Sections

  • Oestrogens and immune function
  • The prime directive
  • Oestradiol – essential to life
  • More from Dr Felice Gersh

By Meleni Aldridge, executive coordinator

I had the immense honour of co-chairing the first Advanced Practitioner Forum, with Dr Indra Barathan, at this year’s Integrative & Personalised Medicine Congress (IPM) in London, on Saturday 8th June, which we at ANH-Intl had had a hand in birthing. We were thrilled to welcome an international star line-up of clinicians and scientists representing some of the best minds in the business and delegates representing many countries.

Clockwise from top left: Dr Kristi Hughes and Rob Verkerk PhD, Dr Wafaa Abdel-Hadi, Deanna Minich PhD, Emily Rydbom, Dr Leslie Stone, Michael Ash, Dr Felice Gersh

In its third year, IPM has grown to be one of the most important congresses for doctors, health professionals and health coaches to attend. The guiding goal of IPM has always been to develop one event that can act as a showcase for the benefits of taking an integrative and personalised approach to medicine that encompasses many modalities and choices. The organisers believe that cohesion and great health change can only come about if everyone comes together to row in the same direction — including politicians and senior advisors within the conventional sector who can (and do) come along to learn and be inspired from the great work that we are all doing.

The Advanced Practitioner Forum is a brand new track added for 2024 for practitioners who wanted the opportunity to deep dive into more clinical wisdom on this year’s theme – ‘The Multi-faceted Immune System’. It was a huge success with delegates calling for more than one day next year.

The 2024 speaker line-up. You’ll find the full programme here.

I’m spoiled for choice as to which excellent talk to feature first, so I’ve chosen to base this article on the presentation by Dr Felice Gersh because she went into an area rarely spoken about, but also because it’s essential knowledge for all of us to know.

Dr Gersh is a board-certified physician in both obstetrics and gynaecology, as well as integrative medicine, who is also a globally recognised expert on women’s hormones, the gut microbiome and circadian rhythms.

Oestrogens and immune function

The entire room was riveted by her talk entitled, Oestrogens and Immune Function. Read on and you’ll see why they’re so important.

The number one take-away is that oestrogen is a critical element of immune function – for men as well as women. It’s not new information that to be healthy, with an optimal immune system, we need to have our full suite of hormones working as nature intended. But what is less well understood is that oestradiol, or estradiol if you’re on the other side of the pond, is essential for the function of the immune system.

As I’m writing this from the UK, I’m going to stick with the English spelling. Oestradiol is one of the 4 oestrogens, also identified as E2. The others being oestrone (E1), oestriol (E3), oestretol (E4). However, oestradiol is so important that men convert testosterone to E2 in different organs and systems. Dr Gersh stressed that this is because every immune response in the human body is related to oestrogen and particularly oestradiol. It’s considered the “mother hormone” and the “master of the immune system”.

Progesterone too is important for immune function and exerts an anti-inflammatory effect, which is why post-menopause when these hormones are in short supply, a woman’s health can take such a downturn. Dr Gersh is a huge proponent of bioidentical hormone replacement therapy (BHRT) and described menopause as a “hormone deficiency state”. She feels that every post-menopausal woman should be on E2/oestradiol BHRT at the very least.

It makes sense. We’re living longer than we did in our evolutionary past, so why not take advantage of what we have in our modern, natural, toolkit to live out our time healthy and well?

The prime directive

From an evolutionary standpoint, the prime directive of life is to procreate and produce new life that is then able to grow to sexual maturity and do the same thing all over again. Like every species here, survival and continuity is also the key driver in the human genetic blueprint. Hence, the female body has evolved for reproductive success.

This means that females have a different immune system to males. In women, the immune system is more robust with more white blood cells, more antibodies, more T-cells and B-cells for example. This is also the reason why autoimmune diseases are more prevalent in women. Women have higher levels of oestrogens, and pregnancy also modulates the immune system through oestrogen.

Pregnancy down regulates all inflammatory cytokines to protect the foetus, which is why many women with autoimmune disease experience remission in their symptoms. When the placenta is delivered (the source of the hormones in pregnancy), autoimmune disease sufferers can experience a huge flare in their symptoms. Some autoimmune diseases only show after pregnancy. The corollary of this down regulation of the immune system is that women who are pregnant are then more susceptible to infections and will have worse outcomes once infected. In evolutionary risk-benefit terms, protecting the foetus is a higher priority to ensure survival of the species.

The overall immune robustness of women has evolved to allow for successful procreation, which is also why women are more likely to survive a pandemic. It’s also why women have a more robust response to vaccines — yet receive the same dose. Dr Gersh asked, “could this be a mistake”?

Oestradiol – essential to life

Below I’ve summarised some of oestradiol’s key actions in the body that Dr Gersh shared in her presentation:

  • Oestradiol modulates the on/off switch for inflammation in the body. The potent health and regeneration systems related to Sirtuin and NAD function depend on the presence of oestradiol
  • Programmed cell death (apoptosis) is dependent on oestradiol. This is the clean-up operation that our body needs to make to ensure we regenerate and create new healthy cells continually
  • Mitochondria, the energy factories in our cells, disintegrate without a sufficient supply of an enzyme called super oxide dismutase. The ensuing biochemical cascade, and many other mitochondrial functions, are dependent on having enough oestradiol
  • Oestradiol helps to maintain our stem cell pool from which new, healthy, cells are made. Fasting can support this further, which is why it has such a positive modulating effect on the immune system. Sufficient oestradiol, supported by fasting can turn people into, what Dr Gersh calls, ‘super agers’!
  • The oral contraceptive pill contains oestradiol’s ‘evil twin’ – EE or ethinyl estradiol, which is able to cause clotting problems. EE goes into the bloodstream and activates a different receptor to natural oestradiol, which, unlike EE, only turns on the inflammatory cascade when you need to it, e.g. for healing
  • Oestradiol is a modulator of inflammation – it starts the inflammatory response, but modulates the inflammatory reaction so you don’t get a cytokine storm
  • Oestradiol is a modulator of the renin-angiotensin-aldosterone system (RAAS), which regulates blood pressure and controls fluid and electrolyte balance through its effects on the heart, blood vessels, and kidneys. It’s one of the main reasons why post-menopausal women have a higher risk of cardiovascular events
  • Oestradiol upregulates our tumour suppressor genes. Each time a woman menstruates, she kills potential cancer cells! Without oestradiol, a woman is more at risk of cancer
  • When using BHRT oestradiol, low doses are more pro-inflammatory than higher doses.

More from Dr Felice Gersh


Integrative Medical Group of Irvine


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