What Are Sugar-Free Drinks Doing to Your Teeth?

Sugar is only half the story

Cavities start when mouth bacteria feed on sugar and make acid. Taking the sugar out of a drink removes that fuel, which is a real benefit.

But many drinks are acidic on their own. That acid can soften the outer layer of your teeth directly, with no bacteria needed. Dentists call this erosion. The American Dental Association points out that carbonation alone makes a drink more acidic, whatever the flavour. So a can of diet pop can still affect your enamel.

How acid wears teeth down

Enamel is the hard, clear shell over each tooth. When acid touches it, minerals start to leave the surface and it becomes slightly softer for a while. Saliva slowly washes the acid away and helps the surface harden again.

Trouble starts when acid comes back before saliva has had time to do its work. Over months and years, the surface gets thinner. Enamel does not grow back once it is gone, so it is worth protecting.

Which drinks tend to be more acidic

Acid levels vary from brand to brand, but these are common sources of acid in a sugar-free diet:

• Diet colas and other diet pop
• Sugar-free energy drinks
• Zero-sugar sports drinks
• Lemon, lime and other citrus-flavoured sparkling water
• Diet iced tea and drink mixes with citric acid

Gentler choices

Plain tap water is the easiest drink on your teeth. In many Ontario communities, tap water also has fluoride, which helps enamel resist acid. Plain milk and unsweetened, non-citrus tea are also low-risk choices for most people.

Plain sparkling water is a middle ground. It is mildly acidic, but usually much less so than pop or energy drinks. Added fruit flavours tend to raise the acid.

How you drink matters as much as what you drink

The biggest factor is often time. One drink with lunch gives your teeth one acid attack. Sipping the same can for three hours keeps your teeth bathed in acid all afternoon. Small habits can make a real difference:

• Finish acidic drinks in one sitting, ideally with a meal, instead of sipping all day.
• Use a straw so less of the drink touches your front teeth.
• Swallow rather than swishing or holding the drink in your mouth.
• Rinse with water afterwards, or have some milk or cheese, which help neutralize acid.
• Chew sugar-free gum to get more saliva flowing.
• Wait about an hour before brushing, so the softened surface can harden again first.
• Brush twice a day with fluoride toothpaste and a soft brush, and floss once a day.

Signs your enamel may be wearing

Early erosion is easy to miss. Watch for teeth that twinge with cold or sweet foods, front edges that look slightly see-through, or teeth that look more yellow because the layer under the enamel shows through. Some people notice small chips, rounded edges or shallow dips on the chewing surfaces.

These signs can have other causes, like grinding or gum recession. That's why it helps to have them checked rather than guessing.

Kids, teens and people with braces

Teens are often heavy users of energy and sports drinks. For most young people, water is all they need during sports. If your child drinks these often, it is worth a chat at their next checkup.

If you wear braces, acid can collect around the brackets and leave chalky white marks once they come off. If you wear clear aligners, take them out before any drink other than plain water. Otherwise the tray holds the drink against your teeth.

What your dentist can do

At a checkup, your dentist looks for early signs of wear and asks about your diet and habits. If wear is found, the first steps are usually simple: changing drinking habits, a fluoride treatment or a toothpaste for sensitive teeth. Where enamel loss is deeper, your dentist may suggest bonding or another restoration to cover and protect the tooth. You will hear the options and get a written estimate before any treatment.

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