Where Does Protein Digestion Begin: 5 Tips & Habits

Where Does Protein Digestion Begin: 5 Tips & Habits


Your protein intake matters, but does it matter how you obtain your protein? Certain factors like when and how often you eat your protein could affect your body’s ability to digest and use it effectively.

Understanding how protein digestion works and incorporating a few habits into your daily routine can help you support your body’s ability to use protein. Fortunately, iwi life is here to help provide some insight into protein digestion and give you some ways you can support protein digestion.

What Is Protein?

Protein is one of life's most important building blocks, found in every human cell and serving a key role in muscle growth and other tissue repairs. Protein is a macronutrient made up of a chain of amino acids.

A range of amino acids can bind together to form a protein — 20, to be exact. The body is capable of synthesizing 11 of these amino acids on its own, whereas the other nine are considered “essential” amino acids since they must be obtained through food.

When a food contains all nine of the essential amino acids, it is called a complete protein. Both plant and animal-based foods can contain protein, but animal-based foods are more likely to be complete proteins than plants.

Where Does Protein Digestion Begin?

Where Does Protein Digestion Begin: # Tips & Habits

While the enzymes in our saliva help us start breaking down carbohydrates and fat, protein does not begin to be digested by the body until it reaches the stomach.

That doesn't mean that your mouth can't play a great supporting role, however! By chewing your food thoroughly, you create greater surface area for the protein-specific digestive enzymes in your stomach to get to work.

Once the protein reaches your stomach, the body begins breaking it down into amino acids. Your stomach breaks down the protein with the help of two chemicals — hydrochloric acid and the enzyme pepsin. These chemicals start the denaturation of the protein, which is the process of unfolding the protein into a peptide chain. This allows the proteins to be more easily broken down into shorter polypeptides, or in other words, smaller amino acid chains.

Some proteins, like insulin, become fully ineffective once they reach the stomach, meaning they need to be used through other methods, like direct injection into the blood.

Protein digestion takes longer than carbohydrate digestion, but not as long as fat digestion. Typically, high-protein meals take longer to digest and break down than other meals, making you feel fuller longer by creating a feeling of satisfaction and delaying your body’s next hunger pangs.

How Does Protein Absorption Work?

Although protein digestion begins as soon as you start chewing, protein absorption happens a bit later. Absorption of protein does not happen until the proteins reach your small intestine. Once the protein is broken down into amino acids in the stomach, it travels into the small intestine and is absorbed into the blood.

After the amino acids have reached your blood, they are brought to the liver and distributed throughout the body as necessary. Amino acids can be used in your body in various ways, depending on where they are needed most. Your body uses amino acids in the following ways:

  • For protein synthesis in cells in various parts of the body
  • To make other nonessential amino acids necessary for protein synthesis
  • To form non-protein molecules that have nitrogen
  • To be stored for future energy sources as fat
  • Converted into glucose, if necessary, to provide energy to the brain and red blood cells

As demonstrated by all of their different functions, amino acids are recycled by the body and used as needed. It is important to maintain a quality diet with a variety of amino acids. Since there is no way for your body to store proteins, you should be sure to get a consistent amount through your diet to keep protein levels in your body where they are needed.

How Can I Make Better Use of My Protein?

Where Does Protein Digestion Begin: # Tips & Habits

Throughout the day, experts recommend about 0.8 grams of protein per kilogram of body weight or about 0.36 grams per pound. Of course, everyone is different, and this amount depends on your lifestyle; factors like frequent exercise and specific health conditions will increase the amount of protein you need.

Regardless, it helps to have the assurance that when you consume protein, your body can digest and use it effectively. To get the most out of your protein, consider the following tips.

1. Eat More Complete Proteins

Animal products like meat, fish, eggs, and dairy are all complete proteins. Plant-based foods like chia seeds and quinoa are also complete proteins. Not every food you eat has to be a complete protein, but you should have some diversity in your diet in order to obtain all of the essential amino acids.

Some food combinations can provide you with complete proteins, like beans and rice, or corn and vegetables. It makes sense that many traditional food combinations make up complete proteins — indigenous people figured this out long ago! 

However, you do not have to stress about receiving complete proteins every meal. If you obtain a variety of the right protein-rich foods throughout the day, your body will likely be able to form complete proteins as necessary.

2. Eat Regularly Throughout the Day

Many people prefer to eat just a couple of big meals during the day, but this is not always the best approach — especially when it comes to maximizing your protein digestion. There is plenty of debate around how much protein you can absorb per meal, but estimates range between 25 to 40 grams of protein per sitting.

If you need 100g of protein throughout the day, you will need to spread your intake over a few meals to ensure that you can absorb all that you need. It may be better to consume protein in the morning instead of later in the day to improve your absorption and intake. In order to cover all of your bases, consider including quality proteins in your diet throughout the day.

3. Take Probiotics

Digestion and nutrient absorption are helped in large part by billions of living organisms in your intestines. Bacteria in the gut play a key role in digestion, and taking probiotics can help support this process, including when it comes to protein.

Taking probiotics may help increase amino acid absorption and formation, particularly for individuals on a plant-based diet. As mentioned, many plant-based proteins are not complete proteins, as they are missing some essential amino acids.

Studies have shown that probiotic intake may lead to an increased presence of amino acids in the blood. As a result, it may be a good idea to take probiotics to maximize the protein formation in the body, especially if you obtain most of your protein through incomplete plant sources.

4. Exercise Regularly

There are many reasons why you should build a habit of exercising regularly, but one of these benefits is improved protein synthesis. After exercise, specifically resistance training or strength training, your body shows higher rates of protein synthesis and lower rates of protein breakdown.

This concept is commonly referred to as the “anabolic window,” which is the idea that you should consume protein within 30 minutes of exercising. However, this concept is a myth. Although protein synthesis is improved after exercise, you do not need to rush to consume protein immediately after a workout.

Combining the habit of exercise with good nutrition is important — research shows that exercising when well-fed may demonstrate better protein synthesis than doing so in a fasted state. At the same time, you may want to avoid intense exercise after a large meal because it may negatively affect your protein absorption.

5. Incorporate Omega-3s 

Omega-3 supplement

Some research shows that omega-3 fatty acids, particularly eicosapentaenoic acid (EPA), may positively affect muscle development by supporting proper protein synthesis in the body.

You can include more omega-3s in your diet by eating more fatty fish, like salmon and mackerel, or using a fish oil supplement. However, some people are on a plant-based diet or would prefer to avoid the aftertaste and unpleasant fishy breath that comes from seafood.

Fortunately, iwi life provides a fish-free, plant-based omega-3 supplement using the power of algae. Just taking two softgels a day could help support your body’s ability to synthesize protein and provide a range of additional health benefits.

Maximize Your Protein Intake

Getting your protein is important, so you should take steps to make sure you get all the protein that you need. By maintaining a healthy lifestyle and incorporating the right nutrients in your diet, you can maximize your body’s ability to use protein.

At iwi life, we want to help you support your health, from your muscles to your heart and beyond. Taking our omega-3 supplement daily is a great way to do just that. Try it for yourself and see all the benefits that omega-3s can offer.



Do I Need to Worry About Eating ‘Complete’ Proteins? | Cleveland Clinic

Probiotic Administration Increases Amino Acid Absorption from Plant Protein: a Placebo-Controlled, Randomized, Double-Blind, Multicenter, Crossover Study | PubMed Central

Exercise training and protein metabolism: influences of contraction, protein intake, and sex-based differences | Journal of Applied Physiology

Protein Digestion and Absorption | Nutrition: Science and Everyday Application

Dietary omega-3 fatty acid supplementation increases the rate of muscle protein synthesis in older adults: a randomized controlled trial | PMC

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