When isotonic drinks are REALLY bad for you!
It all started my my dentist peering into my son’s mouth and then asking me how many fizzy drinks he had. None, well maybe one a fortnight? Hmm, fruit juice? Nope. The dentist’s concerns were that Finn’s teeth were showing considerable acid erosion, this is something different to decay caused by sugar. She was concerned but told us to keep an eye on things for the next six months. Six months past and the next conversation went along the lines of “Are you sure???” In fact the erosion was so severe that Bridget gave us some litmus strips to test everything he was drinking. If it wasn’t in his intake it might be stomach acid.
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The small little indents are caused by acid erosion. |
So we came home and tested one of his milkshake drinks – no problems, we then tested one of his sports drink. Off the scale! Instantly the paper went bright orange indicating high acidity.Everything fell into place really quickly, Finn drinks loads of these but they’re not fizzy and not particularly sweet so I hadn’t really thought of them.
Proposal
What were the pH levels of sport drinks?
Parameters
I was only interested in sports drinks, although I also added a fizzy drink, a fruit juice and an energy drink as bench marks.
Methodology
All drinks were to be tested as soon as the bottle was opened. The pH stick would be rinsed in distilled water after each test. All drinks were done at the same time at room temperature. I wasn’t sure if the composition of the drink altered after a few hours enough to change pH levels but decided not to risk it and did them all at the same time.
Apparatus
pH measure. This had to be calibrated using distilled water and a pH sachet (4.01) – learnt how to make distilled water (I love the internet)
Results
Lucozade Original 3.2
Lucozade Pink Lemonade 3.2
” Orange 3.6
” Isotonic Sport 4.0
” Energy Caribbean Crush 3.4
” Energy Blackcurrant 3.5
” Sport Elite Orange 4.3
” Sport lite orange 4.3
” Revive 3.2
Powerade ion4 Berry 3.4
Tesco Active Isotonic Orange 3.9
Little Big Shot Energy 3.6
Get More Vit D 4.3
” Vit C 3.8
” B Vit 3.7
” Multi 4.5
Fanta Orange 3.7
Coke 3.1
Power Horse Energy Drink 3.7
Mixed Up Stimulation Drink 3.6
Orange Juice 3.5 (this will vary as the fruits vary)
Conclusions
Isotonic drinks are acidic!
Other findings
So citric acid is a massive culprit and if it appears in the top 4 list of ingredients you can guarantee your drink is going to be too acidic. If sugar / syrup is in the top 4 list of ingredients you have given the acid something with which to glue itself to your teeth. Hmm.
If you’re an athlete that wears a gum shields think about how you use it. Typically you will have a slug of your drink and then replace your gum shield. This effectively locks the acid liquid against the teeth. A further problem for athletes is that due to their performance and exertion there is a lack of saliva in the mouth and it’s saliva that washes away sugars and bacteria from the mouth. Replacing saliva with a sugary, acidic drink is a bad swap.
Studies from the 2012 Olympics show that an alarmingly high level of athletes have dental problems.https://bjsm.bmj.com/content/47/16/1054.full?sid=f8500fe6-a508-41ea-a9ca-946db3d9c804
https://articles.ky3.com/2013-05-28/tooth-decay_39483010
https://www.sfsn.ethz.ch/PDF/Mettler_Osmo_pH_Swiss_beverages_SZSM2006.pdf
Further research
I’d like to test a further range of products including energy drinks and sport gels. There also needs to be research into the effects of gumshields on teeth when used with isotonic drinks.
Initial Actions
Drink water. Do not drink anything other than water when using a gum shield. If you drink an isotonic drink, reduce your consumption. Do not brush teeth immediately as dentists are concerned that this additional abrasion may cause further erosion. Although to be honest there aren’t many basins on the race track 🙂
Peer Review
This article has not been peer reviewed unless Facebook and some likes from friends count!