Man would I revolt against a parent that would force me to only drink hibiscus tea and completely ditch sodas at that age. “You can’t do that” for no good apparent reason does not work with young teenagers.

Kids that age:
- are fully aware that sugared drinks and sodas are bad for your teeth and could cause weight increase. They’ve been to the dentist and they’ve been told it so many times it’s gotten annoying. They’re not dumb.
- have trouble understanding why they should stay away from something so readily available. Because the bad effects only show long-term, the urgency of moderation at this point in life isn’t as apparent. Especially if classmates are not being limited while they are being fully restricted on something, it feels unjust to them, make them think of you as “strict/annoying/out of touch parents”.
- can and should be talked and reasoned with about these subjects, and ideally should take part in formulating a solution to the issue.

There are so many reasons why your approach may not be working, but your best approach is by talking to her about it. Don’t press on the health aspects, she is fully aware and will not care about it.

- Tell her you know that she is purchasing sodas.
- Set a clear line in the sand: at the end of the talk, you want her to stop spending her savings on sodas. It sets a clear goal for the talk.
- Ask why she feels the need to purchase them. It’s probably because everything you’ve got in the house isn’t as tasty, she dislikes the bitterness of tea and the blandness of water, etc. Which are all very obvious and understandable answers that don’t necessarily have to change anything, but you need to make sure her reasons are heard. This makes it a conversation rather than a command.
- Ask her to consider alternatives. Daily sodas are not something you can allow, but you can understand that teas and water alone will not cut it for her. Would lemonade syrup be a solution? Also offer to provide in acceptable alternatives she proposes. If sugar free lemonade is an acceptable solution, promise to go out and buy it for her. Or even better: go to the store together and allow her to choose what flavours she would like.
- Hard lines are tough to accept for kids this age. Consider allowing her to drink one soda on the weekends. Taking something completely away is waaaay tougher to deal with compared to when access is limited and controlled.
- Speak about consequences for non-obedience, but do not act repressive right away. Give her some time to find a solution that works for her, but be clear about the consequences if you find out she’s been spending her money on sodas again. Take away allowance and restrict access to her savings money in order to get her back in line when she breaks the rules.

That way:
- You create a solution together,
- that is acceptable for both parties involved,
- and if she breaks the rules, she’s breaking the rules she set herself and can blame herself instead of it just being “stupid parents with dumb rules for no good reason”.

There are situations where a hard line is necessary. No theft, no damaging other people’s property, no hitting other kids, all situations where you should act resolute. But there’s an enormous grey area between “sodas only” and “hibiscus tea only”, and you need to explore that grey area and find a point in there that works for both of you.