Are you someone who has the latest electric toothbrush and diligently brushes after every meal? Perhaps you always pop a travel-sized bottle of mouthwash in your bag and liberally rinse with it throughout the day? Do you buy fancy toothpaste and never forget to floss?

We’re riding a new wave of oral care right now, with all manner of advice on #ToothTok and fancy new products available to keep your breath minty fresh and your pearly whites shiny. But despite these ‘good’ habits, plenty of people still struggle with the occasional (and often painful) mouth ulcer or bleeding gum. And that might be linked to your obsession with dental cleanliness. So, what’s going on?

Well, it’s all to do with your oral microbiome, where over 700 species of bacteria live. According to Holland & Barrett’s recent trends report, the microbiome of the mouth is something we’re going to be hearing a lot more about in 2025, with wellness brands launching a bunch of products tailored to supporting this diverse microbial community. And this new wellbeing focus is important for a reason. 

Healthy teeth and gums result in more than a nice smile. Research has linked oral ill health to all manner of conditions including heart disease, PCOS and endometriosis. One study discovered that patients with chronic periodontitis and gingivitis are twice as likely to develop dementia. To help prevent future issues, it’s important to recognise when your mouth is ‘out of whack’.

“Maintaining a healthy oral microbiome is essential for overall oral and systemic health,” Dr Victoria Sampson, a functional dentist specialising in holistic dentistry at The Health Society, tells Strong Women. “When you don’t brush your teeth, bacteria accumulate on your teeth and gums which can cause ‘dysbiosis’ [an imbalance in the microbiome]. Regular mechanical removal [brushing] of this bacteria is key.” She says telltale signs of dysbiosis are bleeding gums, bad breath, recurrent ulcers and a metallic taste in the mouth. 

But what if you’re keeping everything fresh and clean, and you still experience these symptoms? “There is evidence to show that certain mouthwashes, especially those containing strong antimicrobial agents like chlorhexidine or high levels of alcohol, may destroy the good bacteria as well as the bad,” Dr Sampson adds.

Holistic dentist Dr James Goolnik, founder of Optimal Dental Health, agrees, adding: “I don’t advise the regular use of mouthwash, especially alcohol-based ones. They can kill all the bacteria including the good ones. Overuse can also remove the benefits of fluoride or hydroxyapatite [a natural form of calcium] in toothpaste. Only use it occasionally – maybe once every two weeks – as a deodoriser to mask smells or as prescribed by a dental care professional for short-term use.”  

You may notice symptoms such as sore gums or mouth ulcers flaring up around the same time each month. This may not be down to your dental habits, but it’s possibly a sign of menstrual gingivitis. Step onto the hormone rollercoaster of pregnancy or perimenopause, and oral health issues can become even more exacerbated. And if it’s tempting to reach for the extra-strength mouthwash, it’s worth noting that upsetting the microbiome only makes things worse.

Dr Sampson explains: “As hormones fluctuate, they can create conditions that encourage oral microbiome dysbiosis and it becomes a self-perpetuating cycle. Hormones [such as oestrogen and progesterone] can promote the growth of certain oral bacteria as well as cause increased inflammation and blood flow to the gums making them more susceptible to bacterial colonisation.

“On the flip side, an already imbalanced oral microbiome that has caused inflammation can exacerbate hormone-related oral conditions. Therefore, it’s important to maintain a balanced oral microbiome at all times of life and take extra care of our mouth when our hormones may fluctuate.” 

Any recurrent symptoms should be investigated, recommends Dr Goolnik: “Systemic inflammation is on the increase, and we see it first in the mouth. If you notice bleeding gums when you don’t normally have them, check for a wider issue. It could be pregnancy-related, but often it’s the first sign of insulin resistance or an autoimmune disease. A lot of patients we see with recurrent mouth ulcers have an imbalance in their bodies, so we run blood tests for ferritin, vitamin B12, folate and HbA1c, a marker for blood glucose control.” 

Alongside brushing your teeth morning and night, follow these dental habits to help promote beneficial bacteria and minimise the harmful ones.

Floss daily

“Nearly 30% of bacteria in your mouth is found in between your teeth – it can only be removed by flossing,” says Dr Sampson. She recommends SuperTeeth’s Prebiotic Soft Floss for extra microbiome benefits.

Avoid aggressive mouthwashes

Although she admits some formulas are effective at tackling bad breath and gum disease, that doesn’t mean it should be a daily additive. “Only use mouthwash as a ‘perfume’ to freshen your breath as and when needed, not on a daily basis unless recommended by your dental professional,” she recommends. 

Avoid products containing SLS (sodium lauryl sulphate)

Dr Sampson explains: “SLS is a foaming agent [often found in toothpaste] that can disturb the soft tissue in your mouth and imbalance your oral microbiome. Many people are intolerant to SLS and may have sore gums or ulcers if they use it.” 

Chew gum or suck (sugar-free) mints

“Saliva is what makes the oral microbiome healthy and the bacteria happy. By chewing a mint or gum, you stimulate saliva production, providing more food and nutrients to the good bacteria in your mouth,” says Dr Sampson. 

Practise nasal breathing

It may sound odd, but Dr Goolnik suggests this has benefits for oral health: “Nose breathing is optimal as it helps to warm, filter and moisturise the air you breathe in. It also produces nitric oxide, which helps control blood pressure and stimulate saliva production, reducing the chance of tooth decay. [Conversely] mouth breathing dries out your mouth, leading to bad breath and an increased risk of tooth decay.”

Eat for both gut and oral microbiomes

Just as you would for your gut, Dr Goolnik recommends a varied diet for your oral microbiome: “Eat a diversity of real food. Include probiotic foods, such as unsweetened live yoghurt, kefir, kombucha and fermented foods. Also try and reduce processed foods and sugar.”

Dr Sampson adds: “Include foods high in flavonoids, such as parsley, onions, blueberries, green tea and bananas. If you must have processed foods or sugar, pop in a mint afterwards to help with saliva production.”

Scrape your tongue

You don’t need to own a tongue scraper for this; simply brush your tongue after you’ve done your teeth and rinse away any excess bacteria that’s built up there.

Images: Getty