With regard to lack of evidence, it astonished me, how few HCPs know that pre-oral meds, the only way in which T2 could be treated, was to put people on a low carbohydrate diet. If they looked for them, there are papers and lectures at conferences, books etc.
I've been buying low carb and diabetic diet/cook books from the 1950s and 1960s recently and discovered that back in the Victorian era, they discovered that low carb diets took weight off and high carb low fat put weight on, even with the same amount of daily exercise and calories.
Rebecca Oppenheimer wrote a book on diabetic cookery in 1917 which is widely available online and she too restricted carbs.
Ketogenic diets are used to treat epilepsy at Great Ormond Street Hospital (GOSH) and in USA and other diseases elsewhere.
However, pushing carbs on people with diabetes goes beyond reluctance to break from the medical herd. Big Pharma makes billions out of us and they are constantly pushing for pre-diabetes thresholds to be lowered, around the world.
Credit Suisse did a report on fat published in September which took a year for a team of people, analysing over 400 medical studies, analysing obesity rates, saturated fat intakes, shifts in diet staples, CVD stats and loads more and came to the conclusion that fat isn't a demon. You can download it just Google 'Credit Suisse fat'.
Dr Ancel Keys was neither a medical doctor nor nutritionist, you can find that out from Wikipedia ! His fatally flawed Seven Countries Study cherry-picked data, didn't use multiple linear regression and didn't use computers. Why anyone listened to someone with a PhD in Oceanography and a PhD in Physiology specialising in fish, boggles my mind !
Big Pharma wants their cash cow, the sugar industry wants to peddle their poisons and food manufacturers are all geared up for high carb because maize, potatoes, soya and wheat are relative cheap and can be turned into products which make them several hundred per cent profits.
Governments have vested interests lobbying them, older doctors and dieticians steeped in low fat learning tutting and they don't want to admit that they made a mistake. Imagine the kind of class action that might be launched by Type 2s worldwide if they did.
Meanwhile, according to Credit Suisse, sales of whole milk and butter are going up quite a lot, as consumers make their own decisions.