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The Diary Of A CEO with Steven Bartlett

Most Replayed Moment: Don't Brush Your Teeth After Sugar! The Best Oral Care Routine

Published November 7, 2025
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About This Episode

The conversation focuses on the oral microbiome, particularly the role of specific bacteria such as Fusobacterium nucleatum in tumor growth and oral-systemic health links. Victoria explains how habits like sugar consumption, beverage choices, brushing techniques, and smoking affect oral bacteria, saliva, tooth decay, and gum disease. She also discusses safe approaches to teeth whitening, the use of probiotics for oral health, and practical strategies like proper brushing, flossing, and drinking through straws to protect teeth.

Topics Covered

Oral microbiome Fusobacterium nucleatum Colorectal cancer Breast cancer risk assessment Dental hygiene Sugar consumption Tooth whitening Smoking and oral health Probiotics Saliva

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Quick Takeaways

  • Fusobacterium nucleatum is an oral bacterium associated with accelerated tumor growth in mice and linked to colorectal and breast cancers, but its role is currently considered a risk factor within a multifactorial picture rather than definitively causal.
  • Green tea is highlighted as a simple, effective antibacterial agent against Fusobacterium nucleatum and also provides anti-inflammatory and antioxidant benefits.
  • Coffee and tea do not directly harm the oral microbiome, but they dry the mouth, lowering saliva flow and indirectly promoting harmful bacterial growth, especially when combined with frequent sugar intake.
  • Oral health is strongly influenced by how and when sugar is consumed: concentrated "sugar attacks" are less harmful than frequent sipping that keeps saliva acidic.
  • Brushing should occur first thing in the morning and last thing at night, never immediately after acidic or sugary foods or drinks, and toothpaste should be spat out without rinsing.
  • Electric toothbrushes with timers and pressure sensors often lead to better brushing because many people brush too briefly and too hard with manual brushes.
  • Abrasive whitening toothpastes can damage enamel and increase sensitivity, while professionally supervised whitening can be done in relatively safe ways.
  • Probiotics can help improve the oral microbiome by adding beneficial bacteria, especially when supported by the right diet and prebiotics.
  • Drinking sugary, acidic, or staining drinks through a straw can significantly reduce tooth decay, erosion, and staining by bypassing direct contact with the teeth.
  • Smoking and vaping dry the mouth, constrict blood vessels, mask gum bleeding, and are major risk factors for gum disease.

Podcast Notes

Oral bacteria and their relationship to cancer

Study linking oral bacteria to tumor growth in mice

Description of Fusobacterium nucleatum and tumor acceleration[0:13]
• Victoria confirms awareness of a mouse study showing that Fusobacterium nucleatum can accelerate tumor growth
• She notes this bacterium is implicated not just in mice but also in colorectal cancer and breast cancer in humans

Is the relationship between oral microbiome and cancer causal?

Current view on causality vs. multifactorial cancer risk[0:33]
• Victoria says she would not yet call the relationship causal for most cancers
• She emphasizes that cancer development and aggressiveness are multifactorial with many contributing factors
• Oral health and specific oral bacteria are considered risk factors that can increase cancer aggressiveness or even contribute to initiation

Emerging research targeting Fusobacterium nucleatum

Development of a targeted antibiotic[1:10]
• Victoria mentions ongoing research on an antibiotic designed specifically to kill Fusobacterium nucleatum
• This antibiotic will be given to colorectal cancer patients whose tumors contain that oral bacterium
• Researchers aim to see whether targeting this bacterium slows disease progression or improves prognosis
Potential for establishing stronger causative links[1:34]
• Victoria says that if these trial results are positive, it would strongly support a causative link between Fusobacterium nucleatum and colorectal cancer progression
• For now, she reiterates that the bacterium is best viewed as a significant risk factor within a multifactorial disease process

Sources and management of Fusobacterium nucleatum

What causes higher levels of Fusobacterium nucleatum?

Lifestyle and environmental contributors[1:46]
• Poor oral hygiene is one contributor to elevated Fusobacterium levels
• Genetics can predispose some individuals to higher levels of this bacterium
• Diet is another factor influencing bacterial levels
• Close contact such as kissing can transmit bacteria, making partners potential sources
• Environmental exposure through breathing is also mentioned as a potential source

Role of testing in identifying oral bacteria

Advantages of modern microbiome testing[2:57]
• Victoria highlights the "beauty" of current testing capabilities that allow specific oral bacteria to be identified
• Knowing which bacteria are present enables tailored treatment plans and recommendations

Green tea as a tool against Fusobacterium nucleatum

Antibacterial properties of green tea[2:48]
• Victoria states that green tea is extremely effective at killing Fusobacterium nucleatum
• She describes green tea as anti-inflammatory and helpful against oxidative stress in the body
• Green tea is characterized as antibacterial, contributing directly to reducing Fusobacterium levels
Practical example from a tested individual[2:27]
• Victoria mentions that Jack, who has been tested, has very high levels of Fusobacterium nucleatum that are "really out of control"
• She humorously notes having given him a large amount of green tea as a gift to address this

Impact of coffee, tea, sugar, and fizzy drinks on the oral microbiome

Coffee and the oral microbiome

Direct vs indirect effects of coffee[3:26]
• Victoria, who personally loves coffee, says coffee has no direct negative impact on the oral microbiome
• However, coffee dries the mouth, reducing saliva, which indirectly can cause problems for the oral microbiome

Importance of saliva for oral health

Functions of saliva in the mouth[3:40]
• Saliva is described as critically important: it provides food and proteins for oral bacteria
• Victoria likens saliva to a delivery service that travels around the mouth supplying nutrients to bacteria
• Sufficient saliva helps maintain good bacteria alive and healthy
Consequences of reduced saliva[3:36]
• Dry mouth from coffee, nervousness, or certain medications like antidepressants leads to less saliva
• When saliva decreases, good bacteria lose their food source and die off
• Harmful bacteria can then grow in place of the beneficial ones

Tea consumption and oral health

Tea compared to coffee[4:25]
• Victoria says tea also dries the mouth, though not as severely as coffee
• Apart from mild dryness and staining, she notes no major direct problems from tea itself

Sugar in hot drinks and its effect on teeth

Why sugar in tea is particularly harmful[4:55]
• Victoria warns that adding sugar to tea can be worse than eating a biscuit
• Because sugar dissolves in hot tea and is consumed hot, it can cause more problems for teeth
Concept of a "sugar attack"[5:05]
• She explains that the issue is as much about how sugar is eaten as how much is eaten
• Sipping a sugary tea over one to two hours repeatedly exposes teeth to sugar and acid
• Victoria recommends having all the sugar in one go, creating a single "sugar attack" rather than continuous exposure
• She says this allows saliva to neutralize acidity and return to a healthy state more quickly
Saliva pH cycling and decay[5:28]
• With frequent sipping, saliva repeatedly cycles from acidic to neutral and back
• Over time, this cycling leads saliva to remain acidic, contributing to tooth decay
• She humorously suggests "downing the tea" or eating all M&Ms at once rather than snacking every 10 minutes

Fizzy drinks and artificial sweeteners

Effect of soft drinks on teeth[6:06]
• Victoria says artificially sweetened fizzy drinks are not as bad as drinks with natural sugars
• However, many soft drinks like cola or orange sodas are very acidic
• Their acidity can cause erosion, wearing away the outer enamel layer of teeth with frequent consumption

Strategies for improving the oral microbiome and basic oral care

General recommendations for a balanced oral microbiome

Dietary patterns and sugar frequency[6:53]
• Victoria reiterates aiming for only one sugar attack per day rather than frequent sugar intake
• She notes that frequent sugar alters the pH of saliva, contributing to microbiome imbalance

Core hygiene tools: toothpaste, toothbrush, floss

Keeping oral care simple and effective[7:02]
• Victoria emphasizes that oral care does not need to be overly complicated or expensive
• She stresses the importance of using the right toothpaste, toothbrush, and floss as the most necessary basics

Optimal brushing timing and technique basics

When to brush your teeth

Avoid brushing immediately after sugar or acid[7:31]
• Victoria advises never brushing straight after consuming anything acidic or sugary
• Brushing immediately can grind sugar or acid into teeth, increasing damage
• She recommends waiting 30 minutes after sugar or acid exposure before brushing
Alternative actions right after sugar[8:18]
• Instead of brushing immediately, she suggests chewing sugar-free gum
• She also mentions chewable mints or pastilles that can rapidly neutralize saliva

Most important times to brush

Morning and night routines[8:09]
• Victoria recommends brushing first thing in the morning and last thing before bed
Why nighttime brushing matters most[8:36]
• She calls brushing before bed the most important time
• Brushing for two minutes coats teeth with beneficial toothpaste ingredients
• During sleep, saliva flow decreases dramatically, leaving bacteria "to their own devices"
• Without a protective toothpaste layer, nighttime bacteria can cause significant problems

Spitting vs rinsing after brushing

Why you should not rinse your mouth after brushing[8:41]
• Victoria says you should spit out toothpaste but never rinse with water afterwards
• Rinsing removes the beneficial toothpaste ingredients from teeth and gums
• She uses a sunscreen analogy: rinsing after brushing is like showering off sunscreen right before going into the sun

Choice of toothbrush and correct brushing technique

Electric vs manual toothbrushes

Advantages of electric toothbrushes[9:16]
• Victoria generally prefers electric toothbrushes because they "do the work for you"
• She observes that most people do not know how to brush properly and are not formally trained
• Brushing habits are often passed from parents who themselves may not know proper technique
• People also tend to brush for far less time than they think, averaging only 20-30 seconds instead of the recommended two minutes
• Electric toothbrushes usually have timers to ensure the full two minutes of brushing
• Many electric brushes include pressure sensors that indicate if you are brushing too hard, helping reduce gum recession

Commonly missed areas and specific technique

Most often neglected tooth surfaces[9:54]
• Victoria identifies the inside surfaces of the very back bottom teeth next to the tongue as areas people usually struggle to clean
Angling and movements for effective brushing[10:40]
• She explains that many people brush the inside of these lower back teeth at an ineffective angle
• She recommends raising the elbow and brushing closer to a 90-degree angle on the inside surfaces, near the tongue
• This technique involves brushing slightly onto the gums as well as the teeth
• On the outer surfaces of teeth, she recommends brushing at about a 30-degree angle towards the gum margin
• Circular, rotational movements at this angle help massage the gums and remove bacteria from under the gum before flicking it away
Having a systematic brushing method[11:10]
• Victoria advises against randomly moving around the mouth while brushing
• She suggests following a consistent pattern: for example, start on the left, clean all outer surfaces, then biting surfaces, then inner surfaces, and repeat on the upper teeth

Understanding implants, root canals, and dental pain

Visual model of implants and tooth roots

What an implant looks like in the jaw[11:32]
• Victoria uses a clear tooth model to show how a dental implant appears within the jawbone
• The model also illustrates the natural roots of teeth

Root canals and dental abscesses

Appearance of a tooth with a root canal and infection[11:53]
• On the model, one tooth has black material inside and a red bubble at the root tip
• Victoria explains that this represents a tooth that has had a root canal and now has an infection at the root
• The red bubble symbolizes an abscess in the jaw
• She notes that many people only feel toothache and do not realize what the underlying abscess looks like

Teeth staining and whitening approaches

Types of staining: extrinsic vs intrinsic

Extrinsic staining from external sources[12:36]
• Victoria distinguishes extrinsic staining caused by coffee, tea, and smoking
• She says these external stains are easy to remove
• A hygienist can remove such stains quickly during a cleaning appointment
• Whitening toothpaste might also help with these surface stains

Risks of abrasive whitening toothpastes

Enamel damage and sensitivity[12:52]
• Victoria cautions that many whitening toothpastes are abrasive and can damage enamel over time
• She compares them to exfoliating teeth, noting that tooth surfaces do not grow back
• Repeated abrasion can thin the enamel, leading to sensitive teeth
• When enamel wears away, the underlying dentin, which is more yellow, can show through, making teeth look more yellow instead of whiter

Professional whitening and safety considerations

Need for professional supervision[13:39]
• Victoria advises doing whitening professionally rather than buying random over-the-counter or online kits
• She explains that non-professional products may not have correct concentrations and can severely damage teeth and gums
Variation in professional whitening products[13:39]
• Even within professional whitening, she notes that some products can be bad for teeth while others can be relatively good
• She describes one professional approach they use where one day of whitening is likened in impact to drinking a cola
• She argues that having a cola every day for five or six days is acceptable in the grand scheme and will not massively damage teeth
Existence of safe ways to whiten[14:09]
• Victoria confirms there are safe methods to whiten teeth when done correctly and under proper guidance

Plaque removal and adjunctive cleaning tools

Can plaque be removed at home?

Use of water flossers[14:36]
• Victoria says people can try a water flosser to help with plaque removal
• She notes that home water flossers are not as powerful as the equipment used by hygienists
• The reduced intensity at home is intentional to avoid users damaging their teeth if they use the devices incorrectly

Supplements to reduce plaque buildup

Role of supplements[14:45]
• Victoria mentions that certain supplements can be taken to reduce the amount of plaque that builds up
• She states that these supplements can work quite effectively, though she does not specify types here

Probiotics and the oral microbiome

What oral probiotics are and how they work

Definition and function of probiotics[15:00]
• Victoria explains that probiotics are "good bacteria"
• They are used to introduce beneficial bacteria into the oral microbiome
• Not everyone necessarily needs probiotics, but they can be helpful in specific cases
Importance of the right environment for probiotics[15:12]
• For probiotics to be effective, the oral environment must support their survival
• Victoria notes that if a person is eating the right foods and has adequate prebiotics, the introduced bacteria can continue to grow

Individual variation in good bacteria

Genetic absence of certain beneficial bacteria[15:38]
• She says many people are genetically born without certain good bacteria in their oral microbiomes
• Probiotic products can be used to supplement these missing beneficial strains

Forms of oral probiotics

Mouthwash-type probiotic[15:44]
• Victoria describes a probiotic mouthwash in powder form: you take a teaspoon, mix it with water to activate the bacteria, rinse, and then swallow
• She notes that this provides a two-in-one benefit for both mouth and gut
Chewable tablet probiotic[15:49]
• Another form is a tablet that you chew and then swallow
• She comments that these types of probiotics are very easy to use and that she likes them

Use of straws, smoking, and vaping in relation to oral health

Benefits of drinking through straws

Why straws are important for certain drinks[16:19]
• Victoria says straws are very important when consuming sugar and acid
• Drinking through a straw helps bypass the teeth so that sugary, acidic, or staining liquids go straight to the back of the throat
• This reduces the chance of tooth decay, tooth wear (erosion), and staining
When not to use straws[16:19]
• She notes that if a drink is beneficial for the oral microbiome, such as certain probiotic products, you would not want to bypass the mouth with a straw
• As a personal example, she says she sometimes drinks cola or alcohol through a straw to protect her teeth, except for wine

Effects of smoking and vaping on oral health

Dry mouth and saliva reduction[18:23]
• Victoria states that neither smoking nor vaping is good for the oral microbiome
• Smoking dries out the mouth, reducing saliva and impairing its protective functions
Vascular effects and hidden gum disease[17:20]
• Smoking reduces blood flow to the mouth by constricting blood vessels through nicotine effects
• Because of restricted blood flow, many smokers do not have bleeding gums even when they have gum disease
• Victoria explains that absence of gum bleeding in smokers does not mean gums are healthy; it may simply be due to constricted vessels
Smoking as a major gum disease risk factor[17:47]
• She notes that smoking is very strongly associated with gum disease
• She describes smoking as one of the biggest risk factors for developing gum disease

Lessons Learned

Actionable insights and wisdom you can apply to your business, career, and personal life.

1

Oral health is deeply influenced not just by what you consume, but by how and when you consume it-concentrated "sugar attacks" are less damaging than frequent sipping that keeps your saliva acidic and your teeth under constant attack.

Reflection Questions:

  • • How often during a typical day am I exposing my teeth to sugar or acid in small, frequent doses rather than in a single, contained window?
  • • In what situations do I tend to sip sweet or acidic drinks over long periods, and how could I change that pattern to protect my teeth?
  • • What specific change can I make this week to consolidate my sugar intake into shorter windows instead of constant grazing or sipping?
2

Saliva is a critical protective system for your teeth and oral microbiome, so any habit that chronically dries your mouth-like heavy coffee intake, certain medications, or smoking-can quietly undermine oral and systemic health.

Reflection Questions:

  • • Which of my daily habits might be reducing my saliva flow (for example, caffeine intake, stress, or medication use)?
  • • How could I adjust my routine-such as increasing water, using sugar-free gum, or spacing stimulants-to better support healthy saliva levels?
  • • What is one concrete step I can take over the next week to reduce a dry-mouth-inducing habit and monitor how my mouth feels as a result?
3

Technique and consistency in basic oral care-proper angles, full two-minute brushing, not rinsing away toothpaste, and systematically covering all surfaces-often matter more than buying more products.

Reflection Questions:

  • • If I honestly time my brushing tonight, how long do I actually brush compared to the recommended two minutes?
  • • Where in my mouth (for example, inner back teeth, gumlines) am I most likely to rush or skip, and how could a simple routine pattern help me cover everything?
  • • What small adjustment can I implement today-such as using a timer, changing my brushing angle, or stopping post-brush rinsing-to upgrade my technique without buying anything new?
4

Interventions targeting the microbiome-such as using green tea, probiotics, or tailored hygiene habits-work best when they are informed by testing and paired with an environment (diet, saliva, prebiotics) that lets beneficial bacteria thrive.

Reflection Questions:

  • • What signs, if any, suggest that my current habits might be supporting harmful rather than beneficial oral bacteria (for example, frequent decay, bad breath, gum issues)?
  • • How might I adjust my diet and daily routines to create a more supportive environment for beneficial bacteria before or alongside using any probiotic products?
  • • What is one diagnostic step-such as asking my dentist specific questions about my bacteria or risk factors-that I can take in the next month to better understand my own oral microbiome?
5

Lifestyle choices like smoking, vaping, and unprotected exposure to sugary or acidic drinks can quietly cause gum disease and tooth damage even when obvious warning signs like bleeding gums or pain are absent.

Reflection Questions:

  • • Have I ever assumed my gums were healthy simply because they do not bleed, and how might that assumption be misleading if I smoke or vape?
  • • In what ways could I reduce the direct contact between harmful drinks and my teeth (for example, using straws, limiting frequency) without feeling overly restricted?
  • • What is one realistic harm-reduction or cessation step I could commit to this month if I smoke or vape, specifically with my long-term oral health in mind?

Episode Summary - Notes by Charlie

Most Replayed Moment: Don't Brush Your Teeth After Sugar! The Best Oral Care Routine
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