i can assure you, the biggest reason is chronic elevated blood sugar
you can't even trust the statistics because the whole industry of medicine has been distorted so badly by megacorps and their financier backers interests and their eugenicist agendas, i mean, bill gates shoves it right in your face with his little video with the book about how to lie with statistics sitting on the desk next to him
why do i care about it? because of course my life has been fucked up from very early on by this corporate collusion with government to make it seem like high starch diets are not the same as eating candy all day long
spoiler alert: you might as well be eating candy all day long
there is no such thing as essential sugars, our body can make all the sugars it needs from fats and proteins, we never need to consume these poisons
until a few hundred years ago nobody ate such high starch diets, it's absurd to say that it isn't causing a health epidemic, and it's been going on for centuries already