Even grown-ups get cavities — here’s what’s behind them (and how to avoid them).
When we think of cavities, we often think of kids. But the truth is, tooth decay is extremely common in adults, too — even those who brush every day.
In fact, according to the Canadian Dental Association, nearly 96% of adults have had at least one cavity in their lifetime. So what causes decay in grown-up smiles?
Here are the top causes of tooth decay in adults, plus tips to help protect your teeth for the long haul.
1. 🧁 Frequent Sugar & Acid Exposure
Eating sugar doesn’t automatically cause cavities — but when sugar combines with bacteria in your mouth, it creates acid that erodes enamel.
Cavity risk increases when you:
- Sip sugary drinks (pop, iced coffee, juice) throughout the day
- Snack often, especially on sweets or starchy foods
- Eat sticky or slow-dissolving treats (like gummies or cough drops)
Tip: Rinse your mouth with water after snacking, and try to limit sugar to mealtimes.
2. 🪥 Inconsistent Oral Hygiene
Even adults skip brushing or flossing now and then. But when plaque builds up on your teeth, it creates the perfect environment for decay.
Missed spots — especially between teeth or along the gumline — are where cavities love to hide.
Tip: Brush twice a day with fluoride toothpaste and floss once a day — yes, even at night.
3. 🦷 Worn or Aging Dental Work
Old fillings, crowns, or dental bridges can break down over time, leaving tiny gaps where bacteria can sneak in.
Many adults experience “recurrent decay” — new cavities forming around or under existing restorations.
Tip: Visit your dentist regularly to check the condition of old dental work. Early repairs prevent bigger problems.
4. 😬 Dry Mouth (Xerostomia)
Saliva plays a huge role in cavity prevention — it neutralizes acid and helps wash away food particles. But many medications, health conditions, and even stress can reduce saliva flow.
Dry mouth is a major risk factor for adult tooth decay.
Tip: Sip water often, chew sugar-free gum, and talk to your dentist about saliva substitutes if dry mouth is persistent.
5. 🚬 Tobacco or Vaping
Smoking and vaping not only stain your teeth — they also dry out your mouth and make it harder for your body to fight off infection, increasing your risk of decay and gum disease.
Tip: If you use tobacco, consider cutting back or quitting. Your dentist can support you with resources and oral health strategies.
6. 👄 Gum Recession or Exposed Roots
As we age, our gums may recede slightly, exposing the softer root surfaces of the teeth. These areas aren’t protected by enamel, making them much more vulnerable to decay.
Tip: Use a fluoride toothpaste for sensitive teeth and consider fluoride varnish treatments to help strengthen exposed roots.
7. 🍷 Alcohol & Acidic Beverages
Frequent consumption of acidic drinks — like wine, energy drinks, or even sparkling water — can weaken enamel and lead to erosion over time.
Tip: Drink water between alcoholic or acidic beverages, and avoid brushing immediately after consuming them (wait 30 minutes to protect your enamel).
Final Thoughts
Tooth decay isn’t just a childhood problem — adults face unique challenges when it comes to keeping their teeth strong and cavity-free. The good news? Most decay is preventable with the right daily habits and regular dental visits.
Haven’t had a checkup in a while? Book your appointment today — we’re here to help you catch problems early, avoid fillings, and keep your smile healthy at every stage of life.