Green tea?
 

There's obviously a lot of information out there about green tea, and one of the biggest claims is that is can speed up your metabolism.
Does anyone know if this is true, and in what way exactly does it do this?
Are there any other proven health benefits?
It's hard to separate hard cold evidence and random claims!

There is evidence for prevention of Alzheimers, but you'd have to drink a LOT.

There is an NHS page on Green tea where they have evaluated some of the claims that are made about green tea. here

On the whole it looks like there is limited evidence of it being other than a tasty drink.

Many health claims around "superfoods" are based on misguided science so I would be wary about believing many of the claims around these foods.

Thanks guys, just as I thought- most testing has been on small sample sizes mostly, with varying results and outcomes!
Yes it contains caffeine, but not as much as coffee. I'm aware that the caffeine will have a short term effect on my metabolism, but I was hoping the green tea would have a longer term effect but I guess that's unlikely :-(