A Facebook comment has gone viral this week, with a man 'explaining' exactly how many tampons women should be using each period.
Using maths, the man claimed that an 'average period' is 10mL to 35mL of blood, and therefore since each tampon holds 5mL, a woman should only need seven tampons per cycle.
He then went further, advising that women could just purchase two 64-packs of tampons on Amazon, which would cover them for the year - with some to spare.
Naturally, this post has drawn a lot of criticism, with women pointing out that frankly, periods don't really work like that.
Aside from the issue of period flow changing through the span of the cycle, there is also the health matter of needing to change regularly.