Digestive Enzyme Facts
It may surprise you that there isn't just one enzyme or molecule that breaks down all the food we eat. In fact, the process of digestion, or the breaking down of large pieces of food, is complex and involves several enzymes, each with a specific function. Let's look at the range of enzymes in our digestive system and find out how each one functions to keep us healthy by allowing big pieces of food to become small absorbable molecules.
The food entering our stomach is made easier to digest by the act of chewing and by the addition of moisture from our saliva and the liquid we drink. The stomach contains several enzymes that work together to partially break down the food substance:
Amylase is an enzyme found in our saliva and in the enzyme blend released from the pancrease. It functions primarily as a starch-dissolving enzyme and is the first enzyme to take starch in our food and break it down into simple sugars which can be more easily absorbed. Without something to break down starch, the bacteria residing in our colon would use the starch for food, resulting in bacterial overgrowth, bloating and gas.
Lipase is an enzyme that works throughout the digestive process to break down the fats in our diet. It works with the bile salts excreted from the liver to emulsify and digest long fat molecules. Without lipase, our fat would pass quickly through our system, resulting in the possibility of diarrhea and sometimes leakage from the lower bowel. In addition, our body relies on certain essential fatty acids that can only be derived from food. Without them, our cell structures would not function normally. We would also suffer from extremely dry skin and hair.
Protease is the general term for an enzyme that breaks down proteins. Proteins are molecules that make up much of our living tissue, including our muscles and our internal systemic enzymes. Certain proteins can only be provided through our food. If we have an inadequate means of breaking these down with proteases, we would suffer from what is known as “protein malnutrition”. Much of our body wouldn't be able to function properly without essential amino acids from absorbable protein.
Proteins are broken down in several steps. As most proteins aren't simply long, skinny molecules, they must be “unraveled” from their particular coiled states. Much of this unraveling is done in the acidic environment of the stomach. Proteins do not tolerate an acidic environment unless specifically designed to do so. Once unraveled, proteases break down the pieces of the protein into amino acids that are easily absorbed.
There are a series of special enzymes that are necessary for the breakdown of specific things. Maltase, invertase, sucrase and diastase are all enzymes that break down specific sugars we ingest. Maltase and diastase break down malt sugar—the kinds of sugars you find in malt liquor and other malted foods. Invertase and sucrase also break down sugar but are better able to break down sucrose or table sugar. Those of us with a high sugar intake especially need these enzymes available. If they can't do their job, the bacteria in our gut are the only things that have the advantage. Stomach cramps, bloating and gas can result if the sugar-digesting enzymes are inadequate.
Lactase is another specific enzyme that breaks down the sugar found in dairy products. Without lactase, our ability to drink milk or consume other dairy products would be greatly impaired. As with many enzymes, you don't have to be born with an intolerance to lactose. Any individual who quits consuming dairy products for a period of time may find that when they begin drinking milk again, they are suddenly intolerant. This is because the body gradually “forgets” to make an enzyme that isn't getting used much. In this case, lactase supplementation may become necessary later in life even though an individual hasn't had a problem with lactose intolerance before.
Papain is what makes up meat tenderizer. It works in the digestive system to break up specific segments of proteins into smaller amino acids. Like any enzyme, the temperature and pH conditions of the environment determine how well and how quickly papain does its job. Its optimal pH level is 6-7 which makes it perfect for its use in the duodenum, the part of the digestive system with the highest pH range for digesting proteins and other foods.
Another important digestive enzyme is hemicellulase. This enzyme is vital to the digestion of plant material. Plant cell walls are made from cellulose and are often difficult to digest. Poor plant digestion leaves an excess of roughage that is eaten by bacteria in the colon. The end result is gas and sometimes intolerance to raw vegetables. Hemicellulase keeps this intolerance from happening and maximizes the nutrients that can be absorbed from raw vegetables.
Digestive enzymes are a collection of important molecules without which we would have a very difficult time absorbing our food. If you have problems with food intolerance, gas, bloating, constipation, diarrhea or simply want to maximize the nutrients you absorb, due to the fact that as we age our enzyme production decreases, a proper balance of digestive enzymes can be taken before meals. Also, plant based digestive enzymes are preferred over animal based ones. For more information on plant based enzymes click here.
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