Hello, I'm probably being silly (not uncommon) but it does seem that with and HbA1c of 53% you are diabetic, sorry if this turns out to be the case, (my result in September was 51.7% and I was told over 48% you were diagnosed). However, all the clever peeps have come up with lots of things for you to investigate to clarify your position.
But the good news if you go down the Low Carb High Fat route there are lots of high fat treats for you to help you maintain or raise you weight. It's quite weird to get your head round the "fat" part of the diet, but when the science makes sense, it all clicks. Think cream in coffee, avocado, nuts, cheese, butter. All good for you.