US nutrition labels on food show carbs differently to the UK and Europe, the difference comes down to how they treat fibre.
Fibre is a type of carbohydrate which the human body is unable to digest. As we can’t digest it, it has no impact on our blood glucose levels. We should ignore it when deciding how much insulin to take.
In the UK and EU, the “Carbohydrates” number excludes fibre already. So we don’t have to do any extra calculations, we can just use the number of carbs listed on the packet directly (taking into account portion sizes of course!).
In the US, fibre is included in the “Total Carbohydrates” number, so we need to calculate the “net carbs” in the food.
This “Net Carbs” number is the actual amount of carbohydrates our bodies will convert into glucose and absorb, so we should base our insulin dose off of this “Net Carbs” number.
It’s good to be mindful of this difference so you aren’t caught off-guard when travelling or looking at recipes from a different country. Once you’re aware of it though it’s pretty straightforward to calculate your “Net Carbs”.