Just re read your post.
Just because he says his sugars are fine doesn't mean they are. I used to tell all sorts of fibs to my mum to make her go away especially when i had low sugars. To some extent i still do that today with my wife! I'd advise watching him take a fresh reading and reviewing...
Hi. I've been a type 1 for 16 years now starting at 15 years old. In that time the only occasions when I have had a headache have been when both my blood sugar was low AND my circulation was poor (i used to be a bit fat!). I have no evidence other than my own opinion but as i became fitter and...