Removable braces advice for 14 year old

[Spymum786]

So my son has removable braces for his jaw, he will get the teeth ones after.
I know he is only supposed to drink water and milk but we do let him have juice / smoothies with a straw sometimes.
It's just flavoured water, cordial etc have that citric acid he's supposed to avoid, so wanted to keep to milk and water mainly but just occasional treats of juice as he has no fizzy drinks at all now. I know juice has citric acid too!
Anyone else relate / advise? It's really hard to stick to water and milk and even options of flavouring water contain citric acid!
Thanks

To be honest we didn't bother with the no juice etc rule. He was told he could remove them for eating anyway so had juice etc with meals and brushed his teeth after. Then water in between meals.

Thanks for that, reassuring!
We were told he couldn't remove his unless he was doing sports. I wonder if it's the type of brace?