The gut–hormone connection, explained.
Fluctuating hormones disrupt the gut microbiome — the bacteria that help process oestrogen and shape how mood, sleep and weight feel through perimenopause. Here's the science behind that connection, and the targeted strains we've chosen to support it.
How your gut shapes your hormones
The gut–hormone loop, in five steps. Open any one for how it works and the studies behind it.
01
The estrobolome
The community of gut bacteria that metabolise and recirculate oestrogen.
The estrobolome
The community of gut bacteria that metabolise and recirculate oestrogen.
When the liver finishes processing oestrogen, it tags it for disposal and sends it to the gut. Certain gut bacteria — the estrobolome — can free that oestrogen to be reabsorbed instead of excreted. When the balance shifts, so does how much oestrogen stays in circulation. In a 2024 randomised trial, a probiotic with this β-glucuronidase activity helped maintain oestrogen levels in peri- and postmenopausal women — early clinical proof the estrobolome can be supported.
02
The shift
Diversity drops and the gut barrier weakens through perimenopause.
The shift
Diversity drops and the gut barrier weakens through perimenopause.
The largest menopause–microbiome cohort to date found postmenopausal women have a measurably different, less diverse gut microbiome. Three things move at once: diversity falls, the oestrogen-metabolising species shift, and intestinal permeability and low-grade inflammation rise.
03
The cascade
How that one shift shows up across the body.
The cascade
How that one shift shows up across the body.
We trace the gut connection across four domains — gut comfort, gut–brain (mood, sleep & focus), vaginal & urogenital, and heart, metabolic & immune — and cite the connection for each rather than making one sweeping claim.
04
The research
The papers that anchor the formulation — and the strains in it.
The research
The papers that anchor the formulation — and the strains in it.
Plottel & Blaser (2011) named the estrobolome; Baker (2017) mapped how gut bacteria recycle oestrogen; Peters (2022) — the largest menopause cohort to date — showed the microbiome measurably shifts. On our own strains: Slykerman (2017) found HN001 lowered depression and anxiety in women, and Jones (2012) found L. reuteri NCIMB 30242 reduced LDL cholesterol by around 11%. We cite the nulls too — HN001 showed no effect in a student-stress trial (2022). Transparency is the point.
05
The formulation
How the science becomes Better Gut.
The formulation
How the science becomes Better Gut.
The science above is the brief that produced Better Gut: six strains at 50 billion CFU, chosen as foundational support for the gut microbiome that shifts through the menopause transition.
One shift in the gut, felt across the body
Hormones fluctuate through perimenopause, and the gut microbiome shifts with them — with knock-on effects almost everywhere: mood, sleep, digestion and more. Open each to see the connection and the science.
Bloating & digestive comfort
Usually the first thing women notice. As oestrogen falls, the gut microbiome and its barrier shift — and digestive symptoms climb. This is where foundational gut support starts.
Low mood
The gut makes and regulates much of the body's serotonin and signals the brain along the vagus nerve. As the microbiome shifts in menopause, that gut–brain signalling shifts with it.
Brain fog
Brain fog travels the same gut–brain axis as mood. A shifting microbiome alongside falling oestrogen is increasingly studied as one contributor to menopausal cognitive changes.
Sleep
Sleep runs partly on gut-made signals — serotonin, melatonin precursors and short-chain fatty acids produced overnight. A disrupted microbiome is one input into disrupted sleep.
Vaginal microbiome
The gut and vaginal microbiomes are linked, and both depend on oestrogen. As it falls, protective lactobacilli decline.
Urinary health
Falling oestrogen thins the urogenital lining and changes its microbiome — which is why urinary symptoms become more common in midlife.
Heart & metabolic health
After menopause, cholesterol and cardiometabolic risk climb. The gut microbiome helps regulate how the body handles lipids and glucose — one reason gut and heart health are linked at this stage.
Bone strength
Oestrogen loss drives bone loss — and a "gut–bone axis" is now well described, where the microbiome, gut barrier and inflammation influence bone turnover.
Immune resilience
Most of the immune system sits around the gut. As immune function shifts with age, a balanced microbiome is part of the foundation.
The papers this page is built on
The peer-reviewed studies behind the science here — open any to read the source.
Most probiotics aren't formulated for menopause
A probiotic for menopause should clear a higher bar than "contains live cultures." Here's the standard we hold Better Gut to — and what to judge any probiotic against.
Targeted strains
Named, characterised strains — confirmed by signed manufacturer specification.
A meaningful CFU count
50 billion live cultures per serving — a high count, not the token few million many probiotics settle for.
Chosen for this stage of life
Selected for the perimenopausal microbiome and beyond, not generic gut health.
Honest about the evidence
We're upfront about what the science shows — and where it's still building.
Every strain, and the job it does
Six clinically studied strains. Open one to see what it does and the study behind it.
HOWARU® HN001™
Our only trademarked strain — over twenty years in foods and supplements, 100+ publications, 47+ clinical trials.
Slykerman et al., EBioMedicine, 2017 · Wickens et al., Br J Nutr, 2017 · Chahwan et al., Nutrients, 2024
Lactobacillus rhamnosus
One of the most-studied probiotics in the world, with a large evidence base for gut-barrier integrity and immune support — including reducing antibiotic-associated diarrhoea.
Sindhu et al., Clin Infect Dis, 2014 · Szajewska & Kołodziej, Aliment Pharmacol Ther, 2015
Lactobacillus reuteri
Best evidenced for cardiometabolic health — a randomised controlled trial showed around an 11% reduction in LDL cholesterol versus placebo. As a Lactobacillus, it's also a natural part of the vaginal microbiome.
Jones et al., Eur J Clin Nutr, 2012 · Jones et al., Br J Nutr, 2012
Lactobacillus acidophilus
Studied for vaginal-microbiome support — taken orally, La-14 (with HN001) has been shown to reach and raise vaginal lactobacilli.
De Alberti et al., Arch Gynecol Obstet, 2015
Bifidobacterium lactis
Part of our Bifidobacterium blend — the species is associated with bowel regularity and immune support in adults, both relevant through midlife.
Dimidi et al., Am J Clin Nutr, 2014 (meta-analysis)
Bifidobacterium bifidum
The second species in our Bifidobacterium blend, included for gut-barrier and microbiome-diversity support.
Bifidobacterium & gut-barrier review, 2023
What women tell us after eight weeks
reported a noticeable improvement in bloating
reported an improvement in overall menopause symptoms
reported clearer thinking and less brain fog
Data collection: Method: self-reported survey of 200 Better Gut customers, after ≥8 weeks of daily use.
Trusted by women's health professionals
Dr. Sabrina Ong
"Better Gut is the one probiotic I recommend to all of my patients in perimenopause and beyond. Gut health is foundational in midlife."
Joanna Lyall
“I formulated Better Gut for perimenopausal women specifically — six strains chosen as foundational support for the gut microbiome at this crucial time."
Dr Shahzadi Harper
“The gut–hormone connection is one of the most under-explained parts of midlife health, supporting your gut health during this time can make a real difference."
Dr. Taniqua Miller
"Research shows that the specific bacterial strains in this blend directly address the digestive shifts many women face during midlife and menopause."
The science is the brief.
Better Gut is the foundation.
Six strains. 50 billion CFU. Foundational support for perimenopause and beyond.
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