From the actual study:

> The non-UPF and UPF test meals were closely matched on meal weight, energy, energy density, macronutrients, available carbohydrate, glycaemic index and load, total dietary fibre, sodium and water (all ≤1.6% deviation between meals; Fig. 1b).

So they did match glycemic index, which the article omits.

Would love to read the original research paper if anyone has access to it. My university unfortunately doesn’t.

I believe they are on to something, but wouldn't it be much better if the sample size was larger than just 57 people?