The Digestion and Absorption of Sugar
How does sugar get from our mouths into our bloodstream so it can give us the energy we need to move? Let’s talk a little about digestion and absorption. All of our food is made up of carbohydrates (sugars and starches), fats and proteins. In order for our body to use the nutrients provided, it must break the food down into much simpler pieces so that they can be transported across the intestinal wall and into the bloodstream. Carbohydrates, but specifically sugars, will be our focus. Some foods have naturally occurring sugars, like fruits and milk, and some have added sugars, like cake and cookies. The body isn’t really that concerned about where the sugar came from, but it is concerned with the size of the sugar particle.
Sucrose is usually called table sugar or cane sugar. It is naturally found in fruits and vegetables, and is our go-to sugar for making cookies and cakes. Sucrose is a disaccharide, which is just a fancy way of saying that it is two single sugars bonded together.
The intestinal wall controls what particles can pass through, and in the case of sugars, it only allows one at a time. Picture a revolving door; two people holding hands are walking toward the door but must let go of each other to enter the doorway. Sucrose is like two friends, one named glucose and one fructose, holding hands. This link must be broken, so that glucose and fructose can find their specific doorway, go through it and go into the bloodstream.
For most people this is an easy task. Their small intestine secretes an enzyme (think helper) that will cut the link and separate the glucose from the fructose. The single sugar pieces (monosaccharides) find their doorway and pass through the intestinal wall. The enzyme needed to cleave the sucrose is sucrase. If a person does not have enough of it, some of the sugar they eat could make it through the intestines but never into the bloodstream. In this case, the whole sugar would end up in the large intestine where the local bacteria chew up the sugar and produce unpleasant symptoms, like gas and diarrhea. Proper sugar digestion is critical not only to supply the body with its energy, but also to avoid intestinal issues