From endometriosis to the World Cup. Saliva is telling us far more than we ever imagined.

For years, saliva has been overlooked.

It was something to rinse away, suction up or ignore. Yet here we are, watching it take centre stage in some of the most exciting advances in medicine.

The NHS has announced that it will begin introducing a saliva-based test to help diagnose endometriosis, a condition affecting around 1 in 10 women that takes, on average, 8 to 9 years to diagnose.

Here's the bit I find genuinely remarkable.

The test, Ziwig Endotest, doesn't look at hormones or inflammation markers. It sequences 109 specific microRNAs in saliva using next-generation sequencing, then runs the pattern through an AI model trained to recognise the molecular signature of endometriosis. Ziwig screened over 2,600 candidate microRNAs before landing on that panel of 109.

In the pivotal validation study, published in NEJM Evidence across 971 symptomatic women in 17 hospitals in France, it hit a sensitivity of 96.2% and specificity of 95.1%, an AUC of 0.96. That is diagnostic-grade accuracy, from a saliva sample, for a disease that has historically needed a surgeon and a laparoscope to confirm.

For context, the other approaches making headlines this month aren't saliva at all. Oxford University and Serac Healthcare's new imaging marker still requires a scan. Hera Biotech's MetriDx still requires a biopsy from the womb. Endotest is the only one of the three you can do by spitting in a tube.

Why does this matter?

As a woman, a clinician and someone building a saliva diagnostics company, I can't help but think this is a huge moment.

Not just because it could transform the lives of millions of women, but because it signals something much bigger.

We're finally starting to appreciate that saliva isn't just spit.

It's a biological goldmine.

It contains DNA, RNA, proteins, hormones, antibodies and microorganisms, all of which provide an extraordinary snapshot of what's happening throughout the body.

This is exactly why we built THS Labs. We genuinely believe saliva has the potential to become one of the most accessible and informative diagnostic tools we have.

One of my favourite papers this month was also a consensus publication from the European Federation of Periodontology exploring the relationship between women's health and oral health.

It highlights something we don't talk about nearly enough. Women's hormones influence the mouth throughout life.

Puberty, pregnancy, menopause, polycystic ovary syndrome and endometriosis all affect the gums, saliva and oral microbiome. Likewise, periodontal inflammation may influence reproductive health, pregnancy outcomes and overall systemic inflammation.

The relationship goes both ways.

For years we've separated medicine into neat little specialties.

Dentists look after mouths. Gynaecologists look after hormones. Doctors look after everything else.

But biology doesn't work like that. The body is one connected system.

And while we're talking about hormones… This one is for the men…

With the World Cup now over, I couldn't resist sharing one of my favourite saliva studies.

Researchers collected saliva samples from Spanish football fans before, during and after the 2010 FIFA World Cup Final.

They weren't studying the players. They were studying the fans.

The results were unbelievable.

Simply watching the match caused testosterone levels to increase by almost 30%, while cortisol, our primary stress hormone, increased by more than 50%. Men experienced an even greater stress response, with cortisol levels almost 80% higher than on a normal day.

No running. No exercise. No stepping onto the pitch. Just sitting on the sofa watching football.

It turns out our brains don't always distinguish between participating in a high-stakes event and emotionally investing in one. Competition, uncertainty, excitement and even national pride can all trigger measurable hormonal changes. When fans thought their team would win, their sense of pride increased their testosterone levels and reduced their cortisol levels. I wonder what England's fans' testosterone and cortisol levels were after the Argentina vs England semi finals match a few weeks ago. Testosterone to the floor…

For me, these stories all point in exactly the same direction.

Saliva isn't just becoming a tool for understanding oral health. It's becoming a window into the rest of the body.

Whether it's diagnosing endometriosis years earlier, understanding how hormones influence the oral microbiome, or measuring our physiological response to the biggest football match on the planet, saliva is proving itself to be one of the most powerful and underused diagnostic tools we have.

I genuinely believe that, in the not-too-distant future, providing a saliva sample will become just as routine as having a blood test.

And I, for one, can't wait.

Where can I learn more?
I can't get enough!

I get it. This stuff is fascinating, but it's probably not something many of us were taught at dental school. So where can you learn more?

After such incredible demand, I'm hosting the Health Nexus room at Dentown on Friday 18th September in London - day one of two. We've brought together clinicians and researchers pushing the boundaries of the mouth-body connection, longevity, oral microbiome science and preventative healthcare.

Dr Crystal Marruganti on the oral-skin axis and how periodontal disease influences dermatological conditions. Dr Hugo Madeira on stabilising the oral microbiome to reduce inflammaging. Dr Michelle Jorgensen on separating dental trends from evidence. Dr Devan Raindi on nutrition and periodontal inflammation. I'll be giving a masterclass on saliva diagnostics - where it is now, and why I think it becomes one of the most important tools in preventative healthcare this decade. We close with a panel on where dentistry is actually heading: prevention, personalised medicine, AI, longevity, patient expectations.

If you've ever wanted to understand the science behind the oral microbiome, saliva diagnostics and the mouth-body connection, I'd love to see you there.

Until next month,