I’m going to confess to some aggressive ignorance here because I haven’t gotten a clear answer. Are HFCS (any variant!) chemically identical to sucrose or only “metabolically” identical.
I don’t think they are chemically identical because at a minimum I’ve seen the result of freeze drying solutions of both and HFCS is liquid at STP while sucrose is solid.
So if you’re going to make the argument that they are metabolically identical then go for it but be honest about what you are saying. They may be chemically similar, but so is cellulose.
Obviously they are different chemicals.
In soda because its acidic, sucrose breaks apart to fructose and glucose.
Yes: the two sweeteners have exactly the same metabolic impact. There is no health advantage to sucrose over high-fructose corn syrup. Even outside of soda, your body is extremely efficient at breaking up sucrose; it happens within some number of seconds when your small intestine enzymes hit it. There's a folkloric belief that the sucrose bond gives your body time to more slowly metabolize the fructose; it does not.
If you're going to be making comparisons like this, you should be clear about which HFCS you're referring to. Is it HFCS 55, which is 5% higher in fructose than sucrose is? Or is it HFCS 42, which is 8% lower? If you look this up online, you'll see it summarized roughly as "food: HFCS 42, soda: HFCS 55". If that's the case: none of this matters; caloric soft drinks are poison regardless of how you sweeten them.