Body Identical HRT Versus Bioidentical HRT - what’s the difference?

Medically reviewed by Dr Mandy Leonhardt, MRCGP DRCOG DFFP · 11 August 2026
Differences between Body identical HRT and bioidentical HRT

SISTERLY expert, Susie Perry explains...

When it comes to women’s health and SISTERLY, there’s one female health condition that every woman is likely to need support with, and that’s the menopause! In this blog, SISTERLY nutrition and female health expert Susie Perry explains the difference between bioidentical HRT and body identical HRT and shares her top list of phytoestrogen-rich foods.

With everything that you’ve got going on in your life, it may be hard to spot that you have entered the perimenopause. It’s often not until you feel the rush of your first hot flush or wake up in the middle of the night drenched in sweat or find sex unusually painful, that you start to question if you’ve hit - that stage! However, there may have been plenty of little tell-tale signs that your perimenopause was creeping in.

Early insights

At SISTERLY we are passionate about educating women to identify that they are in the perimenopause as early as possible, so they can get the help and support they need. You can use the SISTERLY Perimenopause Symptom Checklist to see how many symptoms you are currently experiencing. 

Hormone balance is key

Balance is key 

The SISTERLY approach to this hormonal transition is to encourage you to adopt a healthy lifestyle and achieve a sound nutrition baseline from a balanced diet supplemented with a daily sachet of The Elevator. Getting these positive habits in place is a smart foundation to help you cope better with your perimenopause, experience a smoother menopause, and extend your comfort, mobility and mental agility to match your post-menopausal lifespan. 

No time like the present

Generally, symptoms are experienced when levels of oestrogen and progesterone drop below a baseline that your body needs to support areas of your health outside of fertility. That’s right, these two hormones don’t just run your periods, they also have an influence on your nervous system, blood sugar balance, gut, bones, brain and memory. 

During our reproductive years, when we have a regular menstrual cycle, our ovaries should produce enough oestrogen to support our cardiovascular health, bone health and mental wellbeing. Women who ovulate also make progesterone during the second half of their cycle and in some (but not all women) this can have a calming effect on the brain and help with sleep.

As we enter the perimenopausal years, our ovaries become less efficient and hormone production becomes more erratic. Instead of following a cyclical pattern, oestrogen levels can start to fluctuate a lot and go from high to low in a short space of time. These unpredictable fluctuations can play havoc with our nervous system, particularly if you have a hormone sensitive brain. Erratic oestrogen levels can lead to myriads of symptoms which can impact our entire body. As we ovulate less frequently, progesterone levels also start to decline, and this may cause increased anxiety and problems with sleep.

Prescription hormones - what’s safe, what’s natural, what’s best?

HRT was a popular and effective treatment for menopausal symptoms until the publication of the WHI study in 2002 led to a dramatic reduction in HRT prescriptions and leaving women in limbo. We now know that some of the results of this study have been misrepresented, particularly with regards to breast cancer risk and this led to a whole generation of women suffering menopause symptoms needlessly without any support. Since then, we have learned a great deal more about hormones and about HRT. We now know that breast cancer risk is mainly related to the type of progestogen in the HRT. The type of progestogens, which were studied in the WHI study are now rarely used and instead doctors can now prescribe women a much wider choice of HRT regimes which helps to individualise the treatment. One of the HRT options widely available now are body identical hormones.

But don’t get confused between bioidentical hormones and body identical hormones as they are very different. Bioidentical hormones are produced by compounding pharmacies as a customised approach to hormone therapy via private specialists. This is an expensive route involving lots of testing, private appointments, customised dosages all to be approached with caution as this is an unregulated and unlicensed industry which needs substantially more research. 

Body identical hormones contain the same chemical structure as the hormones that your body naturally produces. These regulated and licensed medicines are available on prescription from your GP, at affordable prices and provide dosages inline with what your body is used to.

Body identical oestrogen is available in the form of tablets, gels, patches or sprays and body identical progesterone is taken as an oral capsule. If you live in the UK you can apply for a menopause Prescription Payment Certificate (PPC) from the NHS website for the cost of £18, giving you access to FREE body identical HRT for a whole year! Fabulous news, thank you NHS. Please catch up HSE! 


What about plant sources of oestrogen - is there such a thing? 

If your symptoms are mild, you may find that just increasing plant sources of oestrogen into your diet is enough to hold back symptoms. Foods containing phytoestrogens (lignans, isoflavones, flavonoids) provide a gentle plant source of oestrogen which helps to buffer the times when oestrogen drastically drops too low. 

This is as easy as adding milled flax seeds to your morning smoothie, tahini to your salad dressings and a spoonful of fresh miso to your stir-frys. Research studies reveal that fermented soya beans are bursting with super strength isoflavones so it’s time to pop miso, tamari, tofu and tempeh on your shopping list. 


10 Best Phytoestrogens Foods

  1. Flax seeds
  2. Soybeans 
  3. Sesame seeds
  4. Broccoli
  5. Brussel sprouts
  6. Cabbage
  7. Chickpeas
  8. Lentils 
  9. Prunes
  10. Alfalfa sprouts

Eat more soy to ease menopause symptoms

The Elevator and the menopause 

SISTERLY’S innovative daily women's nutrition supplement, The Elevator, has been formulated with all phases of womanhood in mind, including the nutrients that are often depleted during the perimenopause or that your body requires more of, after the menopause. As an important side note - not all women are suited to HRT (even body identical HRT) and phytoestrogens, this is particularly true for anyone with a family history of hormone-related cancer. For this reason, SISTERLY scientists formulated The Elevator without any phytoestrogens.

For more information on how the individual ingredients of The Elevator help to support you through the menopause, head over to our SISTERLY Lifestyle and read the blog - Elevate Yourself For A Smooth Perimenopause

Find your tribe

Perimenopause through to post menopause demands extra care - these are the years when you want your ‘tribe’, your supporters on the journey with you. This is strongly advocated by Catherine O’Keefe author of All You Need To Know About Menopause and founder of Ireland's popular menopause support site Wellness Warrior

Catherine says; “ An invaluable part is your relationship with your doctor which should be a supportive and collaborative one - if it’s not then please feel empowered to find the right support for you. Visiting a women’s health physio is also key in these years to ensure you maintain strong pelvic health. Empowering yourself with knowledge to navigate these years is crucial so you can make informed choices at all stages and look at the opportunities these years bring too.” 

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