As the tittle says, do we actually absorb the calories from fibre or they just pass through our digestive system untouched?
Insoluble fibers do not provide calories, soluble fibers provide about 2cal/gram (half of regular carbs)
On fiberfacts.org
>Dietary fibers are complex carbohydrates, so some people estimate that they provide 4 calories per gram just like any other carbohydrate. However, others say that calories from fiber don’t count since your body’s digestive enzymes can’t break down fiber. Fibers differ in how well they are digested or how much energy is available to the body. Some fibers, called soluble fibers, either absorb water and become gels or dissolve in water and reach the intestine where they are digested by bacteria. As they are digested by bacteria, soluble fibers produce short-chain fatty acids (SCFAs) that provide your body energy. The US Food and Drug Administration (FDA) estimates that fibers fermented by bacteria provide about 2 calories per gram of fiber. Insoluble fibers travel to the intestine with very little change. Instead of being digested, insoluble fibers increase bulk, soften stool, and shorten transit time through the gastro-intestinal tract. Because these fibers are not digested at all, the FDA estimates that insoluble fibers do not contribute any calories.
This is a very good question and I couldn’t find the answer. I found some sources claiming it has 2 calories per gram, others saying 4, and some saying it doesn’t provide any calories. I know it’s a type of carbohydrate and as you know we humans can’t process it, but I’m not sure if fiber calories are deducted from total calories on food labels.
My USA Type 2 diabetic partner finds that it is wise to count total carbs - as opposed to net carbs - in calculating how a meal will affect Blood Glucose.
Apparently some folks intestinal biome is able to extract / convert / ferment energy from fiber - especially the soluble fiber.
The study of the human biome is still in it’s infancy. I look forward to future understanding of this topic.
I’m not sure if this is correct, but as a RN, (not RD), it seems that pure fiber may actually create a net deficit to overall caloric intake. It certainly works the digestive system, but contributes little or no digested calories. However, the process of working the gut may actually burn more calories than the fiber contributes. Therefore net caloric deficit.