Everything you need to know about digestive enzymes and how they help you digest your food
Digestion is the process which takes place inside the organs of the human digestive system. These organs include the mouth, esophagus, stomach, small intestine, large intestine (colon), and the anus. During the process of digestion, food molecules get broken-down into smaller, water-soluble, substances which can be absorbed into our bloodstream. Digestive enzymes and stomach acid play a vital role in this process and this article will focus on explaining everything about them.
What are the Digestive Enzymes?
Enzymes, in general, are natural catalysts. This means they are substances which accelerate chemical reactions and can break down molecules of other substances into smaller fragments. Digestive enzymes do the same inside our digestive system.
When the food moves through the digestive organs, enzymes which are discharged inside these organs by the secretory glands, break down that food into smaller molecules. There are many enzymes which take part in the process of digestion.
Different enzymes break down different nutrients which make up the foods we eat. For example, proteases and peptidases break down proteins into amino acids. Amylases split carbohydrates (sugars) into glucose and other simpler sugars. Lipases break down fat (lipids) into fatty acids, and so on.
All of these enzymes originate from glands located in different parts of the digestive system such as the mouth, stomach, small intestine, and the pancreas.
The process of digestion starts in the mouth. Salivary glands are responsible for the digestive enzymes produced in the mouth. When food passes through the mouth these enzymes make it softer and soluble, aiding the further digestion.
Mouth enzymes include:
- Lingual lipase – starts the digestion of fats.
- Salivary amylase (ptyalin) – carbohydrates digestion.
Apart from being partially digested, the food is also disinfected inside the mouth. Lysozyme is the mouth enzyme with an antiseptic function in the first stage of digestion.
Stomach enzymes, also known as gastric enzymes, have a very important role in the digestion process. Protein digestion begins in the stomach where Pepsin, a stomach enzyme, splits the proteins into amino acids and peptides.
The other stomach enzyme, Gastric lipase takes part in the digestion of lipids (fats). Gastric lipase is an acidic enzyme which is, together with the Lingual lipase, responsible for 30% of lipolytic activity during digestion in adults.
The stomach also produces other compounds and hormones which assist the digestion process such as Gastric acid, Mucin, Gastrin, etc.
The pancreas is a gland which creates and releases the digestive pancreatic juice. Pancreatic juice is an alkaline liquid which reduces the acidity of the gastric acid and emulsifies the lipids making them easier to absorb. This complex product of pancreas is made up of following digestive enzymes:
- Trypsin which splits proteins into basic amino acids.
- Chymotrypsin which splits the proteins into aromatic amino acids.
- Pancreatic lipase – breaks down triglycerides into glycerol and fatty acids.
- Pancreatic amylase – breaks down glycogen and starch.
Small Intestine Enzymes
Cholecystokinin, a peptide enzyme, is released inside the small intestine. This enzyme is connected with a variety of digestion-related processes in the small intestine. Cholecystokinin increases the release of bile, decreases the flow of digestive juices through the duodenum, and therefore decreases gastric activity leaving more time for the pancreatic juice to neutralize the gastric acid.
Other small intestine enzymes include:
- Gastric Inhibitory Peptide (GIP) – decreases gastric motility
- Motilin – increases gastric motility
- Maltase – breaks down maltose into glucose
- Lactase – splits lactose into galactose and glucose. Lack of this enzyme causes lactose intolerance which is often manifested by abdominal pain, bloating and diarrhea
- Sucrase – breaks down sucrose into fructose and glucose
Digestive Enzyme Supplements
Digestive enzymes can be found in certain foods and as supplements in the form of pills. Foods rich in digestive enzymes are:
- Pineapple, which contains bromelain, a group of proteases.
- Mango (Amylases)
- Papaya (Proteases)
- Honey – very rich in digestive enzymes such as diastases, amylases, invertases, and proteases.
- Bananas (Glycosidase and Amylases)
- Avocados (Lipases)
- Kiwi (Proteases)
Fermented foods, such as yogurt, kefir, kimchi, and sauerkraut also contain digestive enzymes produced by bacteria responsible for their fermentation.
Digestive enzyme supplements are also widely available. They are usually made as chewable tablets or pills which contain one or a combination of several digestive enzymes such as pepsin, lactase, trypsin, amylase, etc. These supplements can support the digestion, help nutrient absorption, assist in pancreatic insufficiency, and ease the symptoms of the Irritable Bowel Syndrome (IBS).
A combination of digestive enzymes supplements and probiotics is a good choice for boosting the digestion. Together with the gluten-free diet, digestive enzymes supplements can assist with relieving the symptoms of malabsorption caused by celiac disease.
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