Sara who told you that?

Normal bloodloss on AF is 25-80ml. A teaspoon is 5ml - so i guess if you lost the minimum you could lose 5ml/day? Is that what you meant?

I used a diva cup before i got Mirena put in, and i lost about 80ml most months (the cup has a measuring scale on it so you can see how much is in it) - i used to fill it full twice on day 1 (40ml) then full once on day 2 (20ml) then just about 5ml/day for 3 or 4 more days. So 75-80ml in total.

A normal blood donation is lots - 470ml-ish - though you can only do that once every 4 months - 4 of my periods would be a loss of 320ml... Never thought about all this before

Bx