Digestive Enzymes: What Do They Do?

Digestive enzymes are  molecules that break down food into simpler portions  so that the body can absorb the nutrients it needs. They accelerate chemical reactions by performing specific functions. Without them, the body cannot perform the process of digestion.

It is important to know that enzymes are in different parts of the digestive tract, ranging from saliva, stomach, fluid in the pancreas to secretions from the intestines. Their location also relates to the function they perform and the conditions they need to be activated.

Let’s take a closer look at it.

What are digestive enzymes?

Enzymes are molecules, typically proteins, that the body produces. They perform their function through many chemical reactions in the body,  but each one of them is specific and has unique substrates on which they act.

This means that even though there are several different types of enzymes, missing one of them can lead to certain problems. This is the case with a lack of lactase, which is the enzyme that breaks down milk sugar, which can cause lactose intolerance.

Types of digestive enzymes

As we mentioned, there are different types of digestive enzymes, and each of them acts on a specific nutrient or substrate. Among them are:

• Amylase in saliva and pancreas  converts starch to glucose.
• Lipase in the stomach and pancreas breaks down lipids into fatty acids and glycerol.
• Cholesterolase and phospholipase break down cholesterol and phospholipids.
• Proteases  are secreted into the interior of the gut in their inactive form and are responsible for breaking down proteins.

What are the enzymes for?

As we mentioned, the body cannot break down the nutrients that are in food without digestive enzymes. Your body would therefore not be able to absorb them. Their action is quite complex, so we will explain how they work below.

1. Decomposition of carbohydrates

The digestion of this nutrient begins in the mouth, where salivary amylase begins to exert its effect. Often  its effects are limited because it depends on the chewing time.

A study published in the  International Journal of Molecular Sciences  says that if a person chews enough on white bread, then they can sense a sweet taste due to the breakdown of starch.

Amylase in the pancreas continues the process of breaking down carbohydrates. The fluid produced in the pancreas  is released when the stomach empties its contents into the small intestine. This enzyme is found in the fluid of the pancreas and there are also lipases and proteases.

Finally, the body can absorb the simplest units of carbohydrates, glucose, fructose and galactose.

2. Degradation of proteins

The digestion of protein begins in the stomach with pepsin produced by the stomach. Most of the digestion of protein  takes place in the first or second part of the small intestine,  where proteases in the pancreas act.

These proteases reach the intestines in their inactive form. This is because if they were activated earlier, they could digest the pancreas and cause major complications.

3. Degradation of fat

The digestion of lipids begins in the stomach with lipase and covers over 10% of the total digestion. Lipase in the pancreas then continues this action when the fat reaches the intestines  and the intestines perform 90% of the breakdown.

For the enzymes that break down fat and cholesterol to work properly, they need bile. The liver produces this and it is stored in the gallbladder.

Upon arrival of fat in the interior of the intestines, and it is noticed by nerve signals, the  gallbladder releases bile  so that it can interact with lipases, phospholipases and cholesterolase, respectively.

Factors affecting the production of enzymes

Several factors can affect the production or function of enzymes. Some of the most common situations are as follows:

• Poor diet.
• Gastrointestinal disorders and malabsorption.
• Pancreatic insufficiency.
• Cystic fibrosis.
• Aging.

One last note on digestive enzymes

Digestive enzymes play a very important role in the breakdown of the nutrients found in foods. When the body is functioning properly, the enzymes also work optimally to convert carbohydrates, fats and protein.

When a metabolic disorder or a situation that changes the production of enzymes occurs, it is likely that foods are not degraded as they should be. As a consequence, it will cause malabsorption and malnutrition.