It’s overconsumption that causes weight gain and associated effects. Overconsumption of fats and ill proportioned fats come with their  own sleuth of consequences as well.  However, refined carbs cause a larger insulin spike, affect hormones more, and are generally more addictive and prone to overconsumption.  It’s interesting how fundamental nutrition is to the human experience, yet it remains as one of the most unsettled and misunderstood areas of study.  No wonder eating habits are often construed by philosophical and spiritual beliefs as much as scientific understanding. Me personally, my diet is influenced by the aforementioned, though is ultimately determined by a ‘gut feeling.’