The phrase "about not realising" is correct and usable in written English.
It can be used when discussing a lack of awareness or understanding regarding a particular situation or fact.
Example: "She expressed her concerns about not realising the impact of her actions until it was too late."
Alternatives: "regarding the failure to recognize" or "concerning the lack of awareness".
By adopting a more holistic approach, it should become clearer if young adults are perhaps underplaying, forgetting about, not realising or unwilling to accept the contribution that all three lifestyle behaviours make to the maintenance of a healthy lifestyle.
Behind him, Alan Shearer was buttoned-up, in more ways than one, though Ian Wright seemed happier to play Ernie Wise to Lineker's Morecambe; it fell to him to deliver the carefully scripted quip about not realising how cold the studio was.
Women skip things about aeroplanes, not realising that this one could affect us right here on the ground.
It still amazes me how unaware some people can be about money: not realising that utility bills are paid quarterly, for example.
Many people in the NHS are naive about politics, not realising that the boards of their heath trusts are run by politicians.
One may care deeply about something, not realising that it is identical to something else one claims not to care about (just as I might greatly admire the speeches of Cicero, and honestly claim to have no time for the speeches of Tully).
I felt so embarrassed about this inequality – not realising that maternity leave could turn you into a sort of Lady Muck – that I took to leaving her alone to clean while I walked the streets of Manhattan.
In January 1960, he talked to a German journalist about these disagreements, apparently not realising that his conversation was being recorded.
You are also in a band called Ambergris that I once wrote bad things about on my blog, not realising that anyone outside of my immediate circle of friends would read it.
"It's not about the colour of your skin, it's about your music," she echoed, not realising that's the exact point people critical of almost entirely white shortlists are trying to make.
Ranjana Bhandari recalls being woken up in the middle of the night by an earthquake about five years ago and not realising what had happened until she saw an item in the news.
