Hi, Well I asked about this last week cause i enjoy puting a little bit of the summer berry into my water, and I was unsure if I was using too much, but my CDC told me not too worry just keep using it was ok
They are £6.00 each and you get Sumer Berry / Orange and Savoury Vegetable
cambridge rules are 1 tsp a day officailly, i know of several people that use it all through the day and have no ill effects but for some people it can have laxitive effect and also has calories even if a small amount.
The first time I ever used it I certainly had a laxative effect, but have been alright since. I didn't realise it was just one teaspoon a day ... I have loads more than that. It's the only way I can get through so much water.