National Smile MonthBetween 12 May and 12 June 2025, the Oral Health Foundation will raise awareness of important oral health issues. Join the nation's biggest oral health campaign and help bring a smile to millions of people. This year the theme for National Smile Month is Feed Your Smile. Find out more Take part About National Smile Month Key messages National Smile Month 2025 Our partners Your oral health Top tips How to clean your teeth Diet and your oral health Oral health & general wellbeing Statistics Feed your smile Diet and a healthy smile Top food tips Smart snacking Hydration and oral health Top dairy foods The gut health link How sugar affects your smile Acidic foods and drinks The worst foods and drinks for your teeth Take part The Smiley Things to do Activities for professionals Activities for schools Fundraising Downloads Shop How sugar affects your smile Sugar is one of the biggest threats to your oral health. It fuels harmful bacteria, weakens enamel, and increases the risk of cavities and gum disease. But it’s not just the obvious sugary treats that cause problems - hidden sugars in everyday foods can also damage your teeth without you even realising it. What happens when you eat sugar? Every time you consume sugar, a process begins in your mouth that can harm your teeth: Bacteria feast on sugar Your mouth naturally contains bacteria, but when they feed on sugar they produce acids. Acid attacks your enamel These acids break down the protective outer layer of your teeth, leading to decay. Cavities form over time Repeated acid exposure weakens enamel, creating holes (cavities) in your teeth. This cycle can last for up to 30 minutes after eating sugar, meaning frequent snacking or sipping on sugary drinks can put your teeth under constant attack. Hidden sugars: the unexpected culprits You may already know that sweets, biscuits, and fizzy drinks contain sugar, but many everyday foods also hide high amounts of sugar. Some common sources include: White bread & breakfast cereals Even "healthy" cereals can be packed with sugar. Flavoured yoghurts & dairy drinks Some contain as much sugar as a chocolate bar. Ketchup & pasta sauces Many condiments have surprising levels of added sugar. Fruit juices & smoothies Even 100% fruit juice contains natural sugars that can damage teeth. Alcoholic drinks & mixers Cocktails and flavoured spirits often contain large amounts of sugar. Checking food labels can help you spot hidden sugars—look for ingredients like glucose, fructose, sucrose, dextrose, and syrups. Tips to cut down on sugar & protect your teeth Swap sugary snacks for healthier alternatives Choose cheese, nuts, or crunchy vegetables instead of biscuits and sweets. Limit sugary drinks Stick to water, milk, or unsweetened tea instead of fizzy drinks and juice. Use a straw If you do have a sugary drink, use a straw to limit contact with your teeth. Chew sugar-free gum This boosts saliva production, helping to wash away acids. Brush & clean interdentally Use fluoride toothpaste to strengthen enamel and remove plaque buildup. Time your sugar intake Eating sugary foods with meals (rather than as snacks) helps reduce the time your teeth are exposed to harmful acids. The bottom line Reducing sugar in your diet is one of the best things you can do for your oral health. By making simple swaps and being mindful of hidden sugars, you can keep your teeth stronger, healthier, and free from decay. Want more advice on protecting your smile? Check out our Best Foods for Teeth guide! Manage Cookie Preferences