This is one of the most one sided depictions of a community. If eating meat and dairy products was the lead cause of heart related disease and diabetes then my grand father who was vegan would not have passed away at a young age. Just because something worked for one person doesn't make it the golden standard for everyone to abide by.
Being vegan or not should be our choice, the type of food we eat depends on the region we live in and the cultivation happening in that area. If people are living in low vegetation areas they tend to eat the available animal base food, similarly people living in an area with high vegetation tent to be vegan.
Just trying to implement an idea on an entire community without understanding the cultural and geographical reason behind it is very bias.