Everything in moderation - including moderation.
There’s an excellent documentary called “The Men Who Made Us Fat” - it’s available on youtube. Key turning points: Secretary of Agriculture Earl Butz getting corn subsidies and promoting high-fructose corn syrup; the sugar lobby who trashed and ridiculed researchers who said sugar was bad, fat was okay; Congress who caved to the sugar lobby by changing their dietary recommendations which led to the low-fat craze (to get low-fat products to taste good, more sugar was added - and diabetes rates soared); and the supersizing marketing of food.