I'm mostly in the 4s and 5s now but, when I started I was in the 9s and 10s. There is absolutely nothing wrong with being in the 5s before a meal. It's quite normal. Aim to be under 7, 2 hours after a meal if you can. I seem to get to about 6.5 occasionally, but that's if I have had something sugary. If I don't, I'll be high 5s and, if I have exercised, I'll be low 5s.
The very low calorie Newcastle Diet is not actually recommended by Roy Taylor of Newcastle Uni. That was an attempt to mimick the effects of having a gastric band fitted. What he does say is:
"Any pattern of eating which brings about substantial weight loss over a period of time will be effective. Different approaches suit different individuals best.
.....
Previous research has shown that steady weight loss over a 5 – 6 month period is more likely to be successful in keeping weight down in the long term. For this reason, ordinary steady weight loss may be preferable"
But what he also says is:
"The extent of weight loss required to reverse type 2 diabetes is much greater than conventionally advised. A clear distinction must be made between weight loss that improves glucose control but leaves blood glucose levels abnormal and weight loss of sufficient degree to normalize pancreatic function."
and
"The role of physical activity must be considered. Increased levels of daily activity bring about decreases in liver fat stores and a single bout of exercise substantially decreases both de novo lipogenesis and plasma VLDL."
So, it's more a question of keeping at it rather than short term fixes.