Why Are My Gums Bleeding When I Brush?

Why does plaque make gums bleed?

Dental plaque is a soft, sticky film of bacteria that forms on teeth. When it accumulates along and just below the gumline, the bacteria release toxins that irritate gum tissue. The gums respond by becoming inflamed — they swell, fill with extra blood vessels as part of the immune response, and become fragile. That fragility is why even light contact from a toothbrush or floss causes bleeding.

This early stage — gingivitis — is reversible. At this point the infection involves only the gum tissue and has not yet spread to the bone or ligaments holding the teeth in place. 1Ref 1Papapanou PN, Sanz M, Buduneli N, Dietrich T, Feres M, Fine DH, et al. (2018).Periodontitis: Consensus report of workgroup 2 of the 2017 World Workshop on the Classification of Periodontal and Peri-Implant Diseases and Conditions.Gingivitis is reversible inflammation confined to the gum tissue; untreated gingivitis may progress to periodontitis involving irreversible bone loss

Is it always gingivitis, or are there other causes?

Gingivitis from plaque is by far the most common cause, but other factors can contribute:

• Brushing too hard or too infrequently — aggressive scrubbing can physically damage gum tissue and increase bleeding; too little brushing allows more plaque to accumulate
• New flossing habits — starting to floss after a long gap almost always causes temporary bleeding, which typically resolves within 1–2 weeks as the gums become healthier 2Ref 2Worthington HV, MacDonald L, Poklepovic Pericic T, Sambunjak D, Johnson TM, Imai P, Clarkson JE (2019).Home use of interdental cleaning devices, in addition to toothbrushing, for preventing and controlling periodontal diseases and dental caries.Flossing in addition to toothbrushing reduces gingivitis compared to toothbrushing alone; temporary bleeding when starting flossing is expected and diminishes as gum health improves
• Blood thinners and certain medications — aspirin, warfarin, and some antihypertensives can increase bleeding tendency; tell both your dentist and prescribing physician
• Hormonal changes — pregnancy, puberty, and the menstrual cycle can temporarily heighten gum sensitivity and bleeding
• Vitamin C or vitamin K deficiency — rare, but severe deficiency can cause gum fragility
• Blood disorders — in rare cases, unexplained persistent bleeding from the gums warrants medical evaluation to rule out a clotting or blood disorder

If gingivitis is so common, why does it matter?

Untreated gingivitis can progress to periodontitis — a more serious infection that damages the bone and connective tissue supporting the teeth. 1Ref 1Papapanou PN, Sanz M, Buduneli N, Dietrich T, Feres M, Fine DH, et al. (2018).Periodontitis: Consensus report of workgroup 2 of the 2017 World Workshop on the Classification of Periodontal and Peri-Implant Diseases and Conditions.Gingivitis is reversible inflammation confined to the gum tissue; untreated gingivitis may progress to periodontitis involving irreversible bone loss Periodontitis is one of the leading causes of tooth loss in adults. Unlike gingivitis, bone loss from periodontitis does not fully reverse. Early treatment matters.

The CDC reports that about 4 in 10 U.S. adults aged 30 or older have some level of periodontitis, with rates rising sharply among adults 65 and older. 3Ref 3Centers for Disease Control and Prevention (2024).About Periodontal (Gum) Disease.About 4 in 10 U.S. adults 30 years or older have some level of periodontitis; prevalence rises to about 60% among adults 65 and older

What should I do if my gums bleed when I brush?

Step 1: Improve your technique. Brush twice daily for two minutes using a soft-bristled brush. Hold the brush at a 45-degree angle to the gumline and use gentle, short strokes. Hard scrubbing damages enamel and gums without removing more plaque.

Step 2: Floss daily. Plaque between teeth can only be removed by floss or an interdental cleaner. A Cochrane systematic review found that flossing in addition to toothbrushing reduces gingivitis compared to toothbrushing alone. 2Ref 2Worthington HV, MacDonald L, Poklepovic Pericic T, Sambunjak D, Johnson TM, Imai P, Clarkson JE (2019).Home use of interdental cleaning devices, in addition to toothbrushing, for preventing and controlling periodontal diseases and dental caries.Flossing in addition to toothbrushing reduces gingivitis compared to toothbrushing alone; temporary bleeding when starting flossing is expected and diminishes as gum health improves Some bleeding is expected when you first establish a flossing routine — it should diminish within 1–2 weeks.

Step 3: See your dentist if it does not improve. Mild gingivitis often responds well to home care, but a professional cleaning removes hardened tartar (calculus) that brushing cannot reach. A dentist can also assess whether gum disease has progressed. 1Ref 1Papapanou PN, Sanz M, Buduneli N, Dietrich T, Feres M, Fine DH, et al. (2018).Periodontitis: Consensus report of workgroup 2 of the 2017 World Workshop on the Classification of Periodontal and Peri-Implant Diseases and Conditions.Gingivitis is reversible inflammation confined to the gum tissue; untreated gingivitis may progress to periodontitis involving irreversible bone loss

Step 4: Consider a new brush. Electric toothbrushes with pressure sensors can help people who tend to brush too hard, and they often outperform manual brushing for plaque removal along the gumline.

Can mouthwash stop gum bleeding?

Antiseptic mouthwashes (containing chlorhexidine, for example) can reduce bacterial load and help control gingivitis, but they are a supplement to brushing and flossing, not a substitute. Chlorhexidine rinses are typically prescribed for short courses by dentists because long-term use can stain teeth and alter taste. Alcohol-free antibacterial rinses are a gentler over-the-counter option that may provide modest benefit in combination with good mechanical cleaning.