How Is Protein Digested

What is Protein Digestion?

Protein digestion is the process of breaking down food into its constituent parts. During this process, digestive juices are released which break down proteins and other nutrients in the food. When digesting foods, your body breaks them down into smaller pieces so they can be absorbed into your blood stream or used for energy. Your body uses different types of enzymes to do this work. Some of these enzymes are called proteases and amylase. These enzymes break down the proteins in the food, while others are called pepsinogen and trypsinogen.

How Does Protein Digestion Work?

When you eat a meal, some of the amino acids (the building blocks of protein) are broken down into their individual amino acid components. Amino acids are made up of four carbon atoms joined together by hydrogen bonds. Each carbon atom of each amino acid consists of two hydrogens and one oxygen. These four elements make up the basic structure of amino acids.

The first step in protein digestion is to break down the food into its component parts. The second step involves breaking those components down further so they can be absorbed into your bloodstream or used for energy.

Protein digestion begins in your mouth and is completed during the process of digestion. It is important to chew your food thoroughly so that the food will be broken down into small pieces when it enters the stomach. During the chewing process, a large amount of salivary amylase (an enzyme) is released and work to break down the carbohydrates in the food. Once the food is swallowed, it enters the stomach where the main chemical digestion takes place.

The next stage of digestion takes place in the small intestine and requires the help of bile and pancreatic juice. The pancreas produces trypsinogen, which is activated by the enzyme enterokinase (which comes from the intestinal lining). Once activated, these two substances go to work breaking down proteins in the food.

How Long Does the Digestion of Protein Take?

The entire process of breaking down ingested gluten takes about four hours.

How Is Protein Digestion Completed?

The first step in the digestion of protein is called chemical digestion and refers to the breaking down of large pieces of food into smaller components. This process occurs in your stomach and begins within your mouth, as the act of chewing breaks down large food particles into smaller ones. Once the food has been chewed sufficiently, it is swallowed and sent on its way to the stomach. There, hydrochloric acid in the stomach juices breaks down the proteins into smaller molecules.

The second step in protein digestion is called enzymatic digestion and involves the addition of specific chemicals or enzymes that “digest” large food fragments into their most basic units. These enzymatic actions begin in the mouth and are completed in the small intestine.

During enzymatic digestion, your pancreas releases two main enzymes that break down proteins into amino acids. These enzymes are called trypsinogen and chyrenjenase. Trypsinogen is activated by enterokinase, which comes from the intestinal lining. Together, these two enzymes break down large protein molecules into smaller pieces.

The small intestine absorbs the amino acids and transports them to the liver, which integrates them into various proteins that are then circulated through the bloodstream.

Amino acids not used by the body are converted to glucose or fat for storage and later use.

Protein Digestion Products

The products of protein digestion are amino acids that are absorbed by the small intestine and sent to the liver. The liver converts these amino acids into proteins that are circulated through the bloodstream and used elsewhere in the body. Any extra amino acids are converted to fat or glucose for storage and later use.

Protein Digestion and the Gluten-Free Diet

If you have been diagnosed with celiac disease, you will be glad to know that the gluten in wheat is handled completely by the chemical digestion process. That means that if you suffer from celiac disease or choose to follow a gluten-free diet, you should still be able to get all of the nutrition you need as long as you eat a varied diet and take vitamin supplements as needed.

Protein is an important part of any diet, but it is especially important for anyone who wants to build muscle. If you are following a gluten-free diet, you can get your daily protein intake from foods such as eggs, meat, nuts, beans and dairy products. Be sure to eat a varied diet with lots of different types of protein to ensure that you consume all of the essential amino acids your body needs to function properly.

Protein can also be found in gluten-free grains such as brown rice, though it contains mostly the generic amino acids and not all of the essential ones. You can also find high protein, gluten-free grains, such as quinoa, that provide all of the essential amino acids in naturally-occurring amounts.

If you want to bulk up or build muscle, you will need to incorporate weight lifting and a high protein diet. You can bulk up faster by increasing your caloric intake and eating more often throughout the day. It’s best to eat 5-6 small meals that are high in protein rather than 3 larger meals.

Muscle building and weight gain go hand in hand and the more muscle you carry, the more calories you burn all day long. Muscle is also better than fat for improving your metabolic rate which helps you burn more calories throughout the day.

Protein is an important part of any diet, especially one that is restricting or involves a lot of physical activity. Always make sure that you get enough protein-rich food so your body can perform at its peak.

Protein is also a good way to fight hunger. By eating high protein foods such as lean meats, beans and dairy, you can reduce your appetite and keep from getting hungry between meals.

The next time you are looking to get in better shape or hit a specific target weight, increase your protein intake. It will help you burn fat, preserve muscle, increase strength and improve your overall health.

On a side note, if you are looking to “bulk up” or add muscle mass, a good protein supplement can give your body the extra nutrients it needs. We recommend MYOS Integrity whey protein powder. It is gluten-free, sugar-free and as pure as it comes. Check it out here.

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Edited by David Vinluan

Sources & references used in this article:

Estimation of the proportion of feed protein digested in the small intestine of cattle consuming wet corn gluten feed by PJ Kononoff, SK Ivan, TJ Klopfenstein – Journal of dairy science, 2007 – Elsevier

The digestion and absorption of protein in man: 2. The form in which digested protein is absorbed by SE Nixon, GE Mawer – British Journal of Nutrition, 1970 – cambridge.org

Increases in ovulation rate in lupin-fed ewes are initiated by increases in protein digested post-ruminally by MB Nottle, PI Hynd, RF Seamark, BP Setchell – Reproduction, 1988 – rep.bioscientifica.com

… the intake of feed by sheep. V. Feed intake and the productive performance of the ruminant lamb in relation to the quantity of crude protein digested in the intestines by RH Weston – Australian Journal of Agricultural Research, 1971 – CSIRO

Effect of transglutaminase treatment on the functional properties of native and chymotrypsin-digested soy protein by EE Babiker – Food Chemistry, 2000 – Elsevier

Characterization of poorly digested protein of cooked rice protein bodies by AP Resurreccion, X Li, TW Okita… – Cereal …, 1993 – online.cerealsgrains.org