While it does not address the root question, one benefit of sugar substitutes is that they are many times sweeter than sugar: stevia is 200-300x sweeter, result

While it does not address the root question, one benefit of sugar substitutes is that they are many times sweeter than sugar: stevia is 200-300x sweeter, resulting in less total mass consumed. My hopelessly-naive-because-biology thought is that each molecule would be metabolized a single time (by your own liver or your microbiome), resulting in less total impact on your body.