I’ve stated my strong suspension that higher glycemic load is the key factor in increasing obesity. Larger portion sizes, more easily digestible carbs and an increase in sweeteners, particularly High Fructose Corn Syrup all contribute to higher GL meals.

Here are two pieces of evidence

One pro

The other contra

I will say that the contra study controls the calories participants consumed while the pro lets people eat what they want, making me think that the pro is a better model. But, of course I am vulnerable to confirmation bias.