Digestibility

Every food we have the opportunity to eat must be processed by the digestive tract. Individual nutrients are metabolized, and this whole process requires a certain amount of energy, time, and effort from the digestive system.
We call these parameters collectively as „digestibility“, which is the fourth rule of the Zone of Optimal Functioning.

We evaluate the digestibility of food on two basic levels. As individual parts, they are relatively easy to understand, but as a whole, it involves two seemingly contradictory parameters:

1. The first part of the definition of digestibility is a factor that is measurable and numerically evaluable. This involves the amount of energy that the digestive tract is forced to expend to digest the food. It is measured in kJ or kcal.

   Generally speaking, the body expends the most energy digesting proteins - approximately 30% of the total energy content found in proteins. Significantly less energy is expended on carbohydrates (about 8%) and the least on fats (approximately 4%).

   In this regard, the difficulty scale of food digestion looks approximately as follows (from the most difficult to the easiest to digest):

   Lean red meat – lean white meat – fatty meat – eggs – cottage cheese – cheeses – legumes – fish – seafood – nuts and seeds – cereals – fermented dairy products – vegetables – mushrooms – fruits.

2. The second part of the definition and perception of the term „digestibility“ is linked to an immeasurable characteristic, which stems from the content of fiber in the food, specifically its indigestible form, and partly also from the content of antinutritional substances (compounds that reduce the nutritional value of food and to some extent complicate the entire digestion process):

   Generally applies - the more insoluble fiber a food contains, the harder it is to digest such food.

   The human digestive tract is unable, unlike ruminants, to produce a spectrum of enzymes capable of breaking down cellulose. In extreme cases, high doses of fiber can lead to bloating, flatulence, mechanical stress on the intestinal tract, and other discomforts in the digestive area.

   In this regard, the scale of digestibility difficulty is as follows (from the most difficult to the easiest to digest, for understandable reasons only concerns plant-based foods):

   Legumes - whole grains of cereals - nuts and seeds - mushrooms - vegetables - fruits.

It is necessary to add for this parameter that thermal treatment of plant foods significantly facilitates their digestibility.

Increased pressure during such treatment further enhances this property (preparation in a pressure cooker).

We can also improve the digestibility of plant foods concerning their fiber content through the process of fermentation (fermentation) – bacteria with their enzymatic activity break down cellulose, thereby significantly facilitating work for our digestive system.

In the overall concept, we can divide foods concerning their digestibility into three groups:

1. Easily digestible
2. Moderately difficult to digest
3. Difficult to digest.