Recent reports revealing that 12% of the country’s three-year-olds already suffer from tooth decay is a painful reminder that the old joke about Brits and bad teeth is not really that funny any more.

Even those of us trying to be good with our oral health might actually be causing more havoc than hope.

So, with that in mind, here’s a quick guide to some unlikely but very unhealthy dental habits…

White wine

Red wine normally gets the bad press for teeth troubles, with all that staining, but it turns out its lighter-shaded cousin is much more irksome.

Research a few years ago by scientists at Johannes Gutenberg University in Mainz looked at the effects of eight red and white wines on the enamel of teeth, removed from men and women aged 40 to 65, for up to 24 hours.

The teeth were carefully soaked in a range of wines and found that those left in the white wine had infinitely more damage than the red.

More recent studies have even suggested red wine can reduce cavities by killing off bacteria in the mouth.

Milk

It’s the stuff of legend that vitamin and calcium-packed milk is good for your teeth. And in that sense, it is. But there’s a catch - milk is also full of the natural sugar lactose, which can cause cavities, especially when left overnight from that ‘before bedtime’ glass.

The key is always to drink milk earlier in the day, so you have time to brush off the sugars afterwards (though not immediately after drinking it – something we’ll explain a little later.)

Yoghurt

Milk isn’t the only dairy product causing problems. The seemingly inoffensive yoghurt is also in the dental firing line, partly because it is highly acidic - which in turn leads to enamel erosion - and partly because fruit yoghurts in particular contain high levels of added sugar. Sugar then reacts with certain bacteria in the yoghurt and begins to erode the tooth.

Natural yoghurt is better, but still not brilliant.

Smoothies

“Every time you sip on a fruit smoothie, your teeth are placed under acid attack for up to an hour,” according to the British Dental Health Foundation.

Yes, the fruit-and-veg drinks might seem healthy with their ‘five-a-day in one bottle’ claims, but after one smoothie from a high-street coffee shop was recently said to contain a staggering 24 teaspoons worth of sugar, it’s more ‘inevitable-cavity in a bottle’.

Fizzy water

We all know by now that fizzy soft drinks are bad for your teeth, but fizzy water seems to have slipped under the radar.

It shouldn’t have done, because while it might not contain the dizzying levels of sugar as other sparkling drinks, the basic process of carbonation means it’s still very acidic on your teeth.

Swimming pools

Another slightly unfair one. You might think you’re being good and healthy, but by going swimming, you’re actually exposing yourself to terrible teeth.

Repeated exposure to the chlorine and chemicals in swimming pool water reacts with the mouth’s saliva and results in brown discolouration of teeth. There’s even a phrase for it: swimmer’s calculus.

Over-keen brushing

It’s natural that if you’ve eaten something you know is bad for your teeth, you want to make amends, but immediately reaching for your toothbrush will actually cause more chaos.

It takes about half an hour for your mouth’s saliva to respond to the acid in food and return to alkaline, and brushing in this time will strip your teeth and expose them to the dangers