I'm not in that league but have lost 17kg from my target of 24kg which would result in a weight of 85kg ( 187lb).
I gained weight rapidly when I stopped smoking because of high blood pressure. With the weight came diabetes, cholesterol, etc.
I started by eating virtually no meat and many vegetables, but lost little.
I then switched to a high protein (at least 50% fish) + veg diet. After an initial loss I stayed much the same but with higher muscle mass, and reducing waistline. This continued for 5 months and at that point I had lost 13cm off my waist.
Continuing with the same diet, the weight started to drop off at around 1 - 2 kg per month.
I've recently added a weekly 10km (6mile) walk to the process.
From 109kg (240lb) I am now 91.6kg (202lb)with 22% body fat.
I test fasting glucose each morning and it is also dropping to the extent that my doctor has reduced medicaments (now 2 X 500mg Metaformin daily). My 3 month rolling average is running at 97.2 mg/dl (5.4mmol/l) and HA1bc is 5.4 .
A highish protein, low fat, little carbohydrate diet, now seems to work consistently. Most importantly I now eat smaller portions and drink less beer.
My Doctors view is that even if I need less than 1 metaformin per day, continuing with the medication will result in longer life expectancy.