Are all types of sugar bad for your teeth?

It’s no secret that sugar is bad for our teeth, and yet in 2020 sugar consumption in Ireland was at 31.2kg per person, more than double the amount recommended by nutritionists. Such statistics raise all kinds of questions – is every type of sugar harmful for our oral and overall health? Do all sugars contribute towards tooth decay and cavities, or are some sugars – especially the so-called ‘natural’ sugars – somehow less harmful?

Dental professionals are quick to point out that all sugars – whether from ‘natural’ sources or processed foods – can lead to tooth decay, and it’s important to remain aware that even ‘natural’ sugars should be enjoyed in moderation, just the same as every other type of sugar. In short, there’s no such thing as sugar that’s tooth-friendly.

It’s widely understood that ingredients and products that feature ‘added sugar’ are the worst for your teeth. Added sugars are especially common in foods and ingredients aimed at children. Worryingly, recent studies have suggested that three-year-olds in Ireland are consuming an average of 10 tsp of ‘free sugar’ (sugars added during the processing and production of food) per day.

Let’s take a closer look at why sugar is bad for your teeth, and why different foods containing sugars – even those from natural sources – should be approached with your dental health in mind.

What makes sugar so bad for your teeth?

Sugars occur naturally in a huge array of vegetables, fruits and other healthy foods. Despite this, sugars aren’t beneficial to your dental health. This is because sugar feeds harmful types of oral bacteria, and when these bacteria feed upon sugar in the mouth, they quickly excrete acids that cause damage to the surface of the teeth. The sugar also helps these bacteria multiply, creating more bacteria which produce more acid… and the cycle continues.

Often, these bacteria end up causing the production of plaque – a film-like sticky substance that adheres to the teeth. Plaque surrounds and encases the bacteria, protecting it as it multiplies. Being aware of this cyclical process is important, and something we should all consider when selecting the food we eat and how we go about our dental health routine.

When choosing our food, it’s helpful to remember that our oral bacteria cannot tell the difference between ‘natural’ or ‘artificial’ sugars – every type of sugar will feed oral bacteria. This includes regular household sugar, grain sugars like glucose, fructose (fruit sugars) and lactose (the sugars present in milk and dairy products). It doesn’t matter what the source of the sugar in your diet is; it can still potentially cause the formation of cavities and tooth decay.

Certain carbohydrates can be broken down into sugar by oral bacteria too. However, sugars formed from carbohydrates produce less energy as others, and bacteria can’t use it to spread quite so quickly. As a result, while the sugar in grains, beans, potatoes, wholemeal bread and other complex carbohydrates won’t benefit your teeth, they also won’t have such a damaging effect, either.

Naturally-occurring sugars vs added sugar in processed foods

Ingredients containing natural sugars – such as dairy products, fruit and vegetables – are a key part of a balanced and healthy diet. The sugars found in these foods aren’t going to cause significant damage to your oral health when enjoyed in moderation and when a good oral health routine is maintained.

On top of this, while the sugars found in natural ingredients have the potential to harm your teeth in the same way as those found in sweet snacks and processed foods, they tend to be balanced by naturally occurring liquids which help to flush sugar and residue away. They’ll also often be present with the kinds of proteins that feed less harmful or beneficial bacteria, as well as fibre which promotes chewing – another tooth-friendly function which increases saliva production.

By brushing and flossing twice daily, visiting a dental hygienist and making regular trips to the dentist, oral bacteria present in the mouth shouldn’t lead to any build-up of plaque.

Foods with added sugars – often processed foods or artificially sweetened ingredients – are generally much worse for your teeth than those with natural sugars. This is because adding sugar to ingredients increases the quantity of sugar that makes contact with your teeth while you eat. Residue from your food will then be more likely to feed harmful oral bacteria, creating a higher likelihood of plaque developing.

Added sugars tend to be modified and processed, which often makes them more viscous and stickier than natural sugars. Caramel is a clear example of this, and it’s a worryingly common ingredient in lots of different foods. Because caramel is a sugar that has been processed into a polymer, it’s even more likely to cling to the teeth where it can feed more harmful bacteria – sometimes for many hours after eating or drinking. These kinds of added sugars are also sometimes artificially separated from natural antioxidants in foods (which help tackle oral bacteria), further compounding the problem.

There’s another issue here: sometimes, food and drinks which we’re led to believe are ‘natural’ are highly processed, and they might even include added sugar to make them taste sweeter. Concentrated fruit juice is a common culprit, and even ‘natural’ treats like dried fruit should be enjoyed in moderation for this reason.

What about alternative sugars and natural sweeteners?

There’s a lot of confusion out there surrounding natural sources of sweetness, and marketing companies put in a lot of effort to make people believe that some of these sugars are ‘healthy’ alternatives. Honey, agave nectar and maple syrup – along with plenty of other plant extracts and alternative sweetening ingredients are often championed as the new big thing in natural sugar… but are they any better than the rest?

On the whole, so-called ‘natural’ sources of sweetness – sometimes referred to as ‘alternative sugars’ are no healthier or unhealthier for your teeth than your standard sugars. Maple and agave syrups are actually just concentrates of sugar syrups and aren’t really ‘natural’ at all – they’re processed ingredients taken from plants other than the standard sugarcane.

Honey has plenty of health benefits, but it is still packed full of sugar that can cause harm to your teeth. What’s more, it’s still a processed product, although it’s processed by bees rather than by humans. It’s also worth mentioning that cheaper honey is sometimes blended with sugar syrup before being packaged and sold.

This brings us back to the point made earlier: it doesn’t really matter what kind of sugar you’re eating as far as your teeth concerned – your teeth can’t tell the difference between the sugar in a chocolate bar or an all-fruit smoothie with maple syrup, and quantity is more significant than quality. Some experts argue that sucrose (which you’ll find in sweets, cereals, chocolates and other treats) is slightly more harmful than glucose and fructose (found in vegetables, fruits and honey) due to its stickiness. However, the difference isn’t particularly significant.

Take steps to ensure a healthy, happy smile

Your diet plays a truly central role in maintaining a healthy and happy smile, and maintaining a great dental health routine alongside regular visits to the dentist will lower your risk of cavities, tooth decay and gum disease.

At Smiles, we take great pride in ensuring our patients’ teeth and gums remain healthy. Our dentists and dental hygienists will spot signs of oral health issues in their early stages, providing treatments and advice that can make a world of difference to your smile.

Make sure you’re attending the dentist and hygienist regularly. To find a local Smiles dentist, search for your nearest practice.

« Back to all articles