Olivia - dentists are on the NHS, free as a full-time student (usually the one based at your uni).
If not, have fun enjoying the experience of trying to find a NHS dentist on the High Street!

Ever since trying Rooibois tea, I've never gone back to normal stuff. It's tea without any of the downsides: no bitterness, you can't over-brew it, no caffeine, and it doesn't stain your teeth.

I like the sound of that!

I've recently developed a penchant for wine.
None of the problems associated with tea or coffee and it's refreshing too! I have heard that continued overconsumption improves your writing abilities (mine were AWESOME after three bottles - or so I thought on the night) but has minor side-effects like cirrhosis, liver failure, increased risk of hepatitis, bad skin, bad teeth, bad BO, loss of dignity and inhibitions.
But I don't believe that.

preaching to the choir! although possibly not during the day?

If I started that I may have to switch to another programe (12 step)

I drink too much green tea and realised my fronth teeth had gone a lovely green colour (not a good look) so I started using whitening toothpaste.

ahh i examined my teeth the other day and was horrified to notice very bad tea stains behind my teeth, no doubt due to my substantial increase in drinking tea since doing phd!! must get my teeth checked too!