Try looking at what actual nutrition scientists say before reading books written by quacks.
I mean people like Kevin Hall, Christopher Gardner, Gil Carvalho - people who have actually carried out randomised controlled trials and metabolic ward studies.
The carbohydrate insulin model has been tested - and there is no evidence to support it.
On the other hand, there is loads of evidence to show that saturated fat intake is linked to increased all-cause mortality compared to mono-unsaturated and poly-unsaturated fat. Which is why I’m disturbed to see people promoting this way of eating.
To be clear, I’m not suggesting eating loads of refined carbohydrates, including sugary food. Most foods high in refined carbohydrates are low in overall nutritional value (vitamins, minerals, fibre, etc) and also high in fat. So high in calories, often not all that filling (generally low protein, low fibre).
What I am suggesting is to stick primarily to unprocessed foods and to follow general healthy eating guidelines - lots of whole grains, fruits, vegetables; moderate protein in the form of legumes, beans, lean meats, fish and small amounts of fat and minimal sugar.
These are not just the UK healthy-eating guidelines, they are pretty much universal in that they are more or less the same in every country on the planet, as far as I can see.
So, either every government and 99.9% of nutrition scientists are part of a big conspiracy and/or have been duped whilst a handful of self-professed “experts” have seen the truth.
Or these guidelines are the best we have to go on given current evidence.