Bleeding Gums: When It's Brushing, When It's Something Else
Clinically reviewed by Dr. Abinaash Kaur, DDS, RCDSO, on 2026-08-18. Dr. Kaur is a general dentist in Toronto (Bloor West Village) registered with the Royal College of Dental Surgeons of Ontario.
Why do your gums bleed? Almost always because plaque has settled along the gumline and the tissue around it is inflamed, and that's the first thing to rule out, not the last. Sometimes, though, the bleeding is a signal from somewhere else in the body: pregnancy, diabetes, smoking, a medication, or once in a long while something rarer.
We've already written a full guide to gum disease itself: When You Floss Every Day But Your Gums Still Bleed. It covers flossing technique, the stages of gum disease, and how we treat it. This post is for the other question patients ask me: what if it's not my brushing?
Is a little blood in the sink normal?
No, and the newest Canadian numbers make the point better than I can. Statistics Canada measured gum health across the country between 2022 and 2024 and headlined the release "gum health is declining" (Statistics Canada).
Their own words: "gum inflammation remained common among Canadians aged 20 to 79 years, with 83% showing bleeding gums in 2022-2024, an important early sign of gum disease" (Statistics Canada).
Read that again: 83%.
Most people see a little pink when they spit, figure everyone gets it, and move on. Health Canada describes healthy gums differently: "firm", "pink in colour (not red)", and "resistant to bleeding during brushing and flossing" (Health Canada).
So bleeding is common. Normal is a different claim.
Brushing every day and still spitting pink? What gives. The first suspect is plaque, the sticky film of bacteria that collects along the gumline. Plaque triggers gingivitis (the early, reversible stage of gum disease), and Health Canada is plain about the fix: "Maintaining good oral hygiene can help prevent or reverse gingivitis" (Health Canada).
Give it two weeks of careful brushing and gentle flossing. If the bleeding fades, it was the plaque. If it doesn't, the rest of this post is for you.
What if you smoke and your gums never bleed?
Here's the myth-bust that matters most on this page. Most people think no bleeding means healthy gums. If you smoke, that rule breaks.
A study of more than 2,000 men in rural Sri Lanka compared tobacco habits with gum bleeding, and the researchers wrote that their findings confirmed "the masking effect of smoking" on it (J Clin Periodontol).
Smoking can quiet the bleeding without quieting the disease.
Health Canada lists smoking among the factors that influence both forms of gum disease (Health Canada). Put those two facts together and the warning light on your dashboard is dimmed exactly when you'd want it working.
I'm not telling you your gums are secretly in trouble. I'm telling you bleeding is a less reliable signal for you, so an exam matters more, not less.
Gum disease "can be hard to recognize in its early stages, as it develops slowly without any real pain" (Health Canada). Smoking makes the quiet quieter.
Does diabetes show up in your gums?
Pretty much, and the traffic runs both ways. The International Diabetes Federation and the European Federation of Periodontology reviewed the evidence together. Their joint consensus calls the relationship bidirectional: each condition can push on the other (joint consensus).
People with periodontitis (the advanced stage of gum disease, where the bone supporting the teeth starts to break down) carry a higher risk of insulin resistance and blood sugar trouble (joint consensus). The link runs the other way at diagnosis too: gum disease is associated with a higher risk of developing type 2 diabetes (joint consensus).
Now the careful part.
The same report links gum treatment to a drop in HbA1c (the three-month blood sugar average) of 0.27 to 0.48 percentage points, measured after 3 months, and the authors note that longer-term studies are inconclusive (joint consensus).
Treating your gums isn't a diabetes treatment. It's one piece of the same puzzle, and it's why I ask about blood sugar at exams.
Why do gums bleed more in pregnancy?
Hormones.
Health Canada counts "hormonal changes (pregnancy)" among the factors that influence gum disease (Health Canada). The shift makes gum tissue react more strongly to the same amount of plaque.
How common is it? A review pooling 20 studies found that 67% of pregnant women, about two in three, had gums that bled when gently checked with a dental probe (J Dent). The rate crept upward as pregnancy went along (J Dent).
Expecting, and noticing the change? Don't shrug it off, and don't back off cleaning the area either. Keep up your cleanings and home care through pregnancy, and our pregnancy and dental health guide covers what we adjust and when.
Could a medication or a vitamin gap be behind it?
It can happen, and it's one of the first things I check in a chart. Health Canada's list of factors that influence gum disease includes "certain medications" (Health Canada). That short phrase is the honest size of the public guidance, so I won't stretch it into a list of drug names.
Try this: bring your full medication list to your next dental exam, doses included. It changes what we look for.
Vitamin C sits in the same drawer. Scurvy, the old sailors' disease of vitamin C deficiency, hasn't vanished. It still turns up now and then, mostly in elderly, malnourished, or alcohol-dependent people, and bleeding gums are one of its signs (scurvy review).
Have no fear about the rarest causes, because what I'm about to describe is rare and looks nothing like ordinary bleeding when you brush. One rare case describes a child whose overgrown, bleeding gums, alongside weakness and recent weight loss, signalled a blood disorder, so we check rather than guess (rare case report).
Does gum disease cause heart disease?
No one has proven that, and I won't tell you otherwise. What the evidence supports is an association. A consensus report from the European Federation of Periodontology and the World Heart Federation backs independent links between severe gum disease and heart disease (consensus report).
Severe gum disease is no niche problem, either. It affects 11.2% of the world's population, which makes it the sixth most common human disease (consensus report).
Association means the two conditions travel together more often than chance would predict. It doesn't mean one bought the other's ticket.
Your gums and your heart share risk factors, smoking among them, and both involve inflammation. Caring for both is the sensible move either way. We've gone deeper in the link between your mouth and your heart and why the mouth is the front door to your body.
Does gum disease cause dementia, or is it the other way around?
Here's where I'll slow down, because the internet has run ahead of the science.
A 2025 review pooled 24 studies and found an association between gum disease and dementia (2025 review). Its authors open by saying the association "remains controversial", which is a sentence worth keeping (2025 review).
Now the part almost nobody quotes.
A large cohort study carries the title "Dementia and the Risk of Periodontitis", and the order of those words is the point (J Dent Res). It followed 8,640 patients with dementia for 10 years. They were nearly twice as likely to develop gum disease as matched people without dementia (J Dent Res).
Did you know about this? The arrow runs in both directions, and no one has proven cause in either one.
Part of it makes plain sense: dementia makes daily brushing and flossing harder, and that alone could explain some of the link. Care for your gums because they're worth caring for, not because a headline promised they'd protect your memory.
When should you stop waiting and book an exam?
If two weeks of careful home care hasn't calmed the bleeding, book an exam. If you smoke, book on a schedule instead of waiting for a signal that may never come. If you're pregnant, diabetic, or starting a new medication and your gums have changed, say so when you book.
At the exam we measure the small pockets around each tooth. Statistics Canada tracked the same measurement, and deeper pockets have grown more common since 2007 to 2009 (Statistics Canada).
Tartar below the gumline doesn't come off with a toothbrush. A deep cleaning is how we clear it, and many patients with active gum trouble do better on a 3 or 4 month cleaning rhythm for a stretch. We've explained how we pick a cleaning interval that fits you.
Nobody here is grading you.
In about 25 years in Bloor West Village, the patients who apologize hardest for their gums are usually the ones who waited longest to come in. Some days the schedule pushes me, and the person in the chair still gets the full explanation and the time it takes. If it's been years, we wrote a note for anyone who's been away a while.
Frequently Asked Questions
Q: Is it normal for gums to bleed when I brush? No. It's common, with 83% of Canadian adults aged 20 to 79 showing bleeding gums in 2022 to 2024 (Statistics Canada), but Health Canada describes healthy gums as "resistant to bleeding during brushing and flossing" (Health Canada). Common and normal aren't the same thing.
Q: Why do my gums bleed even though I brush twice a day? Usually because plaque is sitting where your brush isn't reaching, often between the teeth and along the gumline. Health Canada notes that good oral hygiene "can help prevent or reverse gingivitis" (Health Canada). If two weeks of careful brushing and flossing doesn't settle it, have an exam.
Q: I smoke and my gums never bleed. Does that mean they're healthy? Not necessarily. Research describes a "masking effect" of smoking on gum bleeding (J Clin Periodontol), and Health Canada lists smoking among the factors that influence gum disease (Health Canada). A calm-looking gumline in a smoker still deserves regular exams.
Q: Does gum disease cause heart disease? Cause hasn't been proven. A joint report by the European Federation of Periodontology and the World Heart Federation supports an association between severe gum disease and heart disease (consensus report). Shared risk factors and inflammation likely explain part of the overlap.
Q: Does gum disease cause dementia? Unproven, and the relationship runs both ways. A 2025 review found an association between the two conditions (2025 review), while a 10-year cohort study found people with dementia were nearly twice as likely to later develop gum disease (J Dent Res).
Q: Are bleeding gums during pregnancy expected? They're common: pooled research found 67% of pregnant women had gums that bled when gently probed (J Dent). Hormonal changes make gums more reactive to plaque, so keep up your cleanings and home care through pregnancy rather than pausing them.
Q: Can treating my gums lower my blood sugar? The joint diabetes consensus links gum treatment to a modest HbA1c drop of 0.27 to 0.48 percentage points at 3 months, and notes longer-term studies are inconclusive (joint consensus). It isn't a diabetes treatment, so keep both your dentist and your physician in the loop.
Reviewed by Dr. Abinaash Kaur, B.Sc., DDS (University of Toronto Faculty of Dentistry), who has practised general and family dentistry in Bloor West Village for about 25 years. This article is general oral health information, not a diagnosis or a substitute for an examination.
Gums that bleed, or a change you can't place? Come in and we'll look, measure, and explain what we see in plain words. We're at 750 Annette Street in Bloor West Village, serving the Junction, High Park, and Baby Point. Book a visit with The Village Dentist and we'll take it from there.
