Now accepting Telehealth appointments. Schedule a virtual visit.
Skip to main content

Why a Bedtime Glass of Milk Can Ruin Your Child’s Teeth: The Lactose in It Is a Type of Sugar...

Why a Bedtime Glass of Milk Can Ruin Your Child’s Teeth: the Lactose in It Is a Type of Sugar and Can Be Harmful at Night

Angela Debley took her son Fin, then eight, to the dentist for a check-up, confident that he’d be given the all-clear.

After all, Angela, an admin manager from Bracknell, Berkshire, was a self-confessed ‘health freak’ who was always careful to give her two sons, Fin and Joe, then three, a nutritious diet. She was also meticulous about their dental hygiene.

‘I avoided giving them sweets in favour of what I believed was an extremely good diet full of natural foods,’ says Angela, 40.

‘Instead of fizzy drinks, chocolate and crisps, the kids would have pure fruit juice, muesli bars and granola with natural yoghurt and honey. They also brushed their teeth morning and night.’

When the dentist broke the news that Fin had two cavities in his milk teeth, which had developed since his last appointment six months before, Angela says she ‘felt like the worst parent in the world’ – but she couldn’t work out where she’d gone wrong.

‘The dentist seemed to assume I was feeding him junk food and sweets, which was upsetting because we ate well.’

In fact, it was her children’s healthy diet – and particularly their snacking habits – that had caused the damage.

Angela later learned it wasn’t just the quantity of sugar that was the problem, but the frequency with which teeth are exposed to it. ‘By offering juice, fruit and honey between meals, I was bathing my sons’ teeth in sugar and acid.’

As Professor Damien Walmsley, scientific adviser to the British Dental Association, explains: ‘Children today snack far more often than previous generations, which leaves teeth under constant attack.’

Last month, a Royal College of Surgeons report revealed that one-third of five-year-olds in England suffer from tooth decay, and it is now the leading cause of hospital admissions for under-nines.

The report, The State Of Children’s Oral Health, found that every year 46,000 children were admitted to hospital for multiple tooth extractions – almost 26,000 of those aged between five and nine.

Professor Nigel Hunt, of the Royal College of Surgeons, blamed sugary foods and drinks, saying these should carry cigarette-style warning pictures to highlight the risk to children’s teeth.

But the problem is certainly not confined to children brought up on junk food, or who aren’t taken to the dentist regularly. In fact, dentists say they are seeing more and more children from middle-class homes whose health-obsessed parents are inadvertently harming their teeth.

Dr Rhona Eskander, of the private Chelsea Dental Clinic, says parents are horrified to discover that they have caused their children’s dental decay.

‘Sometimes sporty children may be given unnecessary sports drinks, which are high in sugar and acids that damage teeth,’ she says. ‘Health-conscious parents also like yoghurt drinks – but these “healthy drinks” usually contain high levels of hidden sugars.’

And while a favourite ‘virtuous’ snack is the muesli bar, some cereal bars have twice the levels of sugar as a similar-sized chocolate bar.

There are two ways in which these kinds of foods damage teeth. One is acid erosion, which occurs when teeth are exposed to acidic foods such as fruit and juice. Dried fruit such as raisins may cause acid erosion, too.

Bacteria that live in the mouth cause decay, because as they feed off sugars they excrete an acid that attacks enamel in a similar way to acid erosion

Tooth enamel begins to soften and be destroyed when acid levels in the mouth drop below 5.5 on the pH scale. (Water has a pH of 7, oranges have between 3 and 4.)

After 30 minutes to an hour, saliva, which is alkaline, will restore natural pH balance in the mouth and the enamel will harden, but if the exposure to acid is too frequent – as caused by constant snacking – then the enamel begins to wear away.

This not only makes teeth more vulnerable to decay, but if teeth are brushed within 30 minutes of acid exposure, the softened enamel can be literally scrubbed off.

‘As children’s milk teeth have thinner and softer enamel, they are particularly at risk,’ says Dr Hanel Nathwani, of Reading Smiles in Berkshire. The second major threat is sugar. As Professor Walmsley explains: ‘Bacteria that live in the mouth cause decay, because as they feed off sugars they excrete an acid that attacks enamel in a similar way to acid erosion.’

These bacteria love refined sugar most, but they also feed on honey, and even processed starchy foods such as bread.

‘Acid attacks can last for up to an hour, but teeth can recover provided you limit the sugary foods and drinks to mealtimes only,’ says Professor Walmsley.

Even if it’s only the milk teeth that are affected, this can still lead to long-term problems.

Angela used to give her sons muesli bars as an after-school snack

‘If children have to have milk teeth removed, teeth start to shift to fill the space, so their second teeth can’t grow into their natural position,’ says Dr Nathwani. ‘This can affect the alignment of their teeth, and mean the child is more likely to need braces.’

He adds: ‘I often see parents who feed their families generally great diets and are very shocked when they learn that their children have tooth decay because of these apparently healthy foods.

‘I feel for them, as they are trying their best to do the right thing.’

This rang true for Angela. Fin and Joe would have four or more snacks a day, such as granola and honey mid-morning, milk at night, plus juice and fruit whenever they wanted it during the day.

She used to give her sons muesli bars as an after-school snack.

‘I thought they were a healthy alternative to sweets and biscuits, but after I moved the family to Dr Nathwani’s practice, I looked more closely at the labels and noticed they were packed with more sugar than a chocolate bar.’

Angela gave the children milk before bed, thinking the calcium would be good for their teeth. However, Dr Nathwani says: ‘While milk during the day is fine, the lactose in it is a type of sugar and can be harmful at night, as when we are asleep we produce less of the saliva that would neutralise it

Angela is far from the only health-conscious parent to discover she’s unwittingly exposed her child to tooth decay.

Louise Jones (a pseudonym, as she’s too embarrassed to give her real name) discovered her ‘fruit monster’ son needed four fillings at the age of seven because he constantly snacked on oranges, grapes and apples.

‘My family call me the “fridge Nazi” at home, because I’m so careful with my children’s diet,’ she says. ‘I was very proud that he loved fruit so much.

‘I was horrified when his dentist told me that my son had such bad teeth because constant exposure to acid in fruit was literally dissolving the enamel on his teeth. I now give fruit at mealtimes and just once a day as a snack.’

The fad for smoothies doesn’t help, as Dr Uchenna Okoye, of London Smiling dental practice warns. ‘Juice from fruits has a high acid content and can damage the enamel of your teeth in exactly the same way as fizzy drinks do.’


You Might Also Enjoy...

Manual vs. Electric Toothbrush: Which Is Better?

You know you should brush at least twice a day and floss at least once. But should you use a manual toothbrush or invest in an electric one? Is one better than the other? The answer to the latter is Yes. Find out which here.
 How (and Why) to Floss Better

How (and Why) to Floss Better

Unlock your best smile by mastering the art of flossing. Read on to learn how to improve your flossing technique and why this should be a priority when it comes to dental hygiene.
8 Lesser-Known Hacks to Keep Your Teeth Healthy8 Lesser-Known Hacks to Keep Your Teeth Healthy

8 Lesser-Known Hacks to Keep Your Teeth Healthy

We all know the basics of good oral hygiene — brushing twice a day, flossing once a day, and going to the dentist a couple of times a year — but it shouldn’t stop there. Read on for our lesser-known hacks to keeping your mouth healthy.
 10 Tips to Prevent Bad Breath

10 Tips to Prevent Bad Breath

How many times have you found yourself in close quarters and wondered about your breath? Bad breath can be problematic, and it could even indicate a serious health issue
How Can Periodontal Treatment Benefit Me?

How Can Periodontal Treatment Benefit Me?

Periodontal treatment focuses on your gums and other structures that support your teeth. Having a dentist with experience in these treatments ensures you receive optimal care for all your oral health needs.