You clearly have perfectly valid reasons to need that time. My advice is that blocking out a chunk of your day (rightfully or not) will mark you out to directors, etc as someone less flexible/useful than the rest.It wasn't something that couldn't have waited half an hour.
As far as I'm concerned my lunch hour is my time to do with as I please. I also use the hour to get things done that need to be done, like personal stuff for my mum, she's just been diagnosed with alzheimers so she is going to rely on me and my sister heavily as time goes by. That's the kind of thing they wouldn't want you to do during work time (the owner sent out a long email having a go at people doing personal stuff on their PC's during work time and he was tinkled off. And tbh, rightly so) so I use the hour for personal time.