Not all Food Calories are equal and here's why...
The calorific value of polyols/sugar alcohols like Isomalt, Xylitol, Erythritol, or Maltitol is lower than that of sugars because of the way they are digested...
Most polyols are primarily fermented in the large intestine, rather than absorbed in the small intestine, which has important consequences for their energy value.
If a carbohydrate (like sugar) is absorbed in the small intestine and not excreted via urine, it becomes fully available to the body as energy, whereas if a carbohydrate (like a Polyol) is fermented in the colon, only about half of it (50%) will be available as energy. When a polyol is ingested, a significant part of it (varying from 10% to 99% depending on the individual polyol) is not absorbed in the small intestine and therefore enters the large intestine.
The "real" energy value of a polyol is therefore dependent on the following three factors, which must all be considered when calculating a polyol’s energy value:
- the percentage of polyol that is absorbed in the small intestine as opposed to the percentage that is fermented in the large intestine
- the extent to which the body can use any energy from the polyol absorbed in the small intestine
- the part that ends up in the large intestine.
So, in summary, calories from Polyols, which are listed on food labels are not necessarily what the body is taking in.