A healthy intake of protein can positively impact one’s overall health, especially for the physically active who want to make the most out of their workouts. Some drink their protein shakes to get an energy boost, but what’s the science behind it? Does protein give you energy? 

The article bares all the truths of how protein provides the body with energy. 

What Is Protein?

Popularly called the building blocks of life, proteins play many important roles in the body that help structure, function, and regulate the body’s tissues and organs. Regularly taking protein can create a positive difference in one’s overall health, especially for athletes and physically active people.

Sources & Types Of Protein

There are various types of protein sources, the most common ones used in protein powder supplements include:

Animal-based proteins 

• Whey –  This milk-based protein is the most popular kind of protein powder due to its ability to effectively promote muscle protein synthesis and lean muscle mass growth.
• Casein – Like whey protein, casein is another milk-based protein that effectively boosts muscle mass growth. What makes it different from whey is that it’s digested more slowly than other proteins, which helps reduce appetite and promote better metabolism.
• Egg – Eggs are a rich source of protein. Both the egg white and the yolk contain protein, but the amount of egg white (albumen) is greater than the yolk, the latter has a greater protein concentration compared to the albumen.

Plant-based proteins 

Plant-based sources of proteins include 

• Soy – Soy protein is the primary protein found in soy-based foods like tofu, tempeh, and soy milk.
• Peas – Pea protein is a high-quality protein sourced from yellow peas, which is rich in branched-chain amino acids and other minerals. 
• Nut & seed – Protein-rich nuts and seeds include hemp seeds, chia seeds, pumpkin seeds, peanuts, almonds, pistachios, sunflower seeds, flax seeds, and sesame seeds.
• Grain – Grains high in protein include cornmeal, wheat berries, quinoa, rice, millet, couscous, and oatmeal. 

These protein sources are classified into two types – complete and incomplete proteins. A complete protein contains all of the amino acids, while incomplete proteins don’t. All animal-based proteins are complete proteins, but some plant-based proteins are incomplete protein sources, so they have to be combined with other complete plant-based proteins like soy, pea, and seed in the right proportion to obtain a complete profile. 

Amino Acid Profiles

The body’s digestive system processes the protein into individual amino acids, which are absorbed and used by cells to create new proteins. A protein powder’s amino acid profile shows the quantity of each amino acid per serving found in a product. Amino acids are molecules that combine to form proteins. They also help break down food, grow and repair body tissue, and make neurotransmitters.

The nine principal amino acids include:

• Histidine
• Isoleucine
• Leucine
• Lysine
• Methionine
• Phenylalanine
• Threonine
• Tryptophan
• Valine

The Role of Protein in the Body

One of the primary functions of protein consumed in the diet is to build and repair cells and tissues, including the muscle cells damaged when exercising to momentary fatigue, and are responsible for their structure, function, and regulation. 

Protein also facilitates hormone regulation, especially during the transformation and development of cells during puberty. It also creates enzymes, which are proteins that help speed up chemical reactions in our bodies and are essential for digestion and liver function.

Eating protein after physical activity stimulates muscle protein synthesis, inhibits protein breakdown, and even stimulates net muscle protein accretion. Since hair and nails are mostly made of protein, it’s important to take proteins regularly for proper nail, hair growth, and overall skin health. 

Protein As A Source Of Energy

Protein isn’t a primary source of energy in the body. It’s one of the last things the body would use as an energy source and it does so by metabolizing the protein for energy. 

An instance where the body would use protein for energy is when you’re either fasting, experiencing a prolonged calorie deficit, or lacking in carbohydrates. When the body does use protein as an energy source, it causes adverse effects on the body. For example, the muscles start to degrade and as a result, they become smaller and weaker over time.

Carbohydrates are the main energy source of the human diet, while fats are the slowest source of energy but the most energy-efficient form of food. They’re better suited for providing energy since the body maintains them as reserves for use as fuel. Moreover, they’re metabolized more efficiently compared to protein, which requires more energy to digest compared to fats and carbohydrates, taking about 20-30% of total calories in protein consumed to digest.

The Biochemistry of Protein and Energy

The proteins, lipids, and polysaccharides found in the food we eat are broken down into smaller molecules before the cells use them, either as an energy source or to build other molecules. The breakdown processes must act on food taken in from outside, but not on the macromolecules inside our own cells.

Then follows the process of gluconeogenesis, where the body converts non-carbohydrate sources, including protein, into glucose for energy. Net gluconeogenesis occurs during starvation and after a meal high in fat and protein without carbohydrates.

Protein and Energy: Myths and Misconceptions

Myth 1: Protein Is the Best Source of Energy for the Body

The myth:

Some people believe that protein is the primary source of energy for the body.

The truth:

Carbohydrates and fats are the body’s preferred sources of energy. While protein can be used for energy, it’s primarily used for growth and repair. It’s one of the body’s last resorts for energy and happens only during fasting, a prolonged calorie deficit, or lack of carbohydrates in diets.

Scientific evidence

Carbohydrates and fats are more metabolized efficiently than protein, which requires more energy, which studies show requires about 20 to 30% of total calories in protein consumed to fully digest.

Myth 2: Consuming Extra Protein Gives You More Energy

The myth

Taking more protein than the recommended daily intake (RDA) or its maximum absorption limit will give more energy.

The truth

Consuming more than the RDA of protein doesn’t necessarily provide more energy. However, this excess protein can be stored as fat, and its digestion can use more energy.

Scientific evidence

A study published in the Journal of the International Society of Sports Nutrition shows that muscle protein synthesis is maximized at a protein dose of around 20 to 25 grams, which means the body can absorb a maximum of 25 grams of protein in one sitting (a period of 1.5-2 hours after a meal). 

That said, if you consume more than 25 grams of protein in one sitting, the body won’t utilize it for energy nor give muscle growth an extra boost. The excess protein will be stored as fat in the body. 

Myth 3: Protein Supplements Are Essential For Energy For Athletes

The myth

Athletes depend solely on protein supplements to maintain energy levels and improve performance.

The truth

Though it’s true that athletes and other physically active people do need more protein in their than sedentary individuals, they can get enough protein through a balanced, protein-rich diet. Protein supplements are beneficial, but they’re not essential for everyone.

Scientific evidence

Even in the absence of protein supplements, eating protein-rich whole foods is an excellent way to meet one’s protein needs. Studies show that consuming protein-rich foods like poultry, beef, fatty fish, nuts, milk, eggs, rice, beans, seeds, and peas is still the more effective way to suffice a person’s daily protein needs.

Myth 4: Plant-Based Proteins Don’t Provide Enough Energy

The myth

Only animal-based proteins can provide sufficient energy.

The truth

While it’s true that animal-based proteins contain all nine essential amino acids, a few plant-based sources like soy, pea, and hemp do have a complete profile. The plant proteins with an incomplete amino acid profile are usually mixed with other plant-based proteins to suffice the amino acids they lack. 

Scientific evidence

Studies show that soy protein is rich in branched-chain amino acids which the body can utilize as an energy source. Soy protein helps with weight loss and building muscle. It can manage hormone balance and prevent cardiovascular problems and osteoporosis.

FAQ Section

Recap

• In select dire instances, protein does provide energy, but it can severely degrade the muscles. Carbohydrates and fats remain the body’s primary energy sources.
• Carbohydrates are metabolized more efficiently compared to protein, which takes up more calories to burn. 

Conclusion

Consuming a healthy amount of protein helps facilitate the body’s most vital functions. While it does provide energy, it only does so during a few instances, but it can affect muscle mass and cause them to waste away, so it’s important to never depend on protein for energy.  

If you’re looking to maximize your energy sources, ask a dietitian to help you better weigh your options.