Collagen Amino Acids Explained: Why Glycine, Proline and Hydroxyproline Matter

Collagen has become one of the most talked-about supplements in the wellness world and for good reason. As the most abundant protein in the human body, collagen plays an essential role in supporting our skin, joints, bones, muscles, hair and connective tissues.

But what makes collagen so beneficial?

The answer lies in its unique amino acid profile.

Collagen contains a specific combination of amino acids that help support the body’s natural structure, repair processes and overall health. Unlike many other protein sources, collagen is particularly rich in glycine, proline and hydroxyproline, amino acids that are especially important for maintaining healthy connective tissue.

This blog will cover the amino acids found in our collagen, explain their roles in the body and explore why collagen supplementation can be beneficial.

What Are Amino Acids?

Amino acids are often referred to as the building blocks of protein. They are used by the body to build and repair tissues, support hormone production, aid digestion, contribute to muscle growth and help maintain healthy skin, hair and nails.

There are 20 amino acids in total, some of which are:

• Essential amino acids - these must come from the diet because the body cannot produce them itself
• Non-essential amino acids - these can be made by the body
• Conditionally essential amino acids - these may become more important during periods of stress, illness, ageing or recovery

Collagen contains a broad range of amino acids, but it is especially known for its high concentration of glycine, proline and hydroxyproline.

The Amino Acid Profile of Collagen

The amino acid composition of collagen is different from many other proteins. This unique structure is what gives collagen its strength and supportive properties.

Below are some of the key amino acids found in our collagen, it has a naturally rich amino acid profile that helps support the body’s connective tissues, skin, joints and overall wellbeing.

The Amino Acid Profile in Our Collagen

Our collagen contains a naturally occurring range of amino acids, including:

• Glycine – 22.1g per 100g protein
• Proline – 13.3g per 100g protein
• Hydroxyproline – 11.0g per 100g protein
• Glutamic acid – 10.0g per 100g protein
• Alanine – 8.8g per 100g protein
• Arginine – 8.1g per 100g protein
• Aspartic acid – 5.6g per 100g protein
• Lysine – 3.6g per 100g protein
• Serine – 3.3g per 100g protein
• Leucine – 2.9g per 100g protein
• Valine – 2.4g per 100g protein
• Phenylalanine – 2.2g per 100g protein
• Threonine – 1.8g per 100g protein
• Isoleucine – 1.5g per 100g protein
• Histidine – 1.3g per 100g protein
• Hydroxylysine – 1.1g per 100g protein
• Methionine – 0.8g per 100g protein
• Tyrosine – 0.3g per 100g protein

This unique amino acid composition is what gives collagen its supportive role within the body.

Glycine

Glycine is the most abundant amino acid in collagen.

It plays an important role in:

• Supporting collagen formation
• Maintaining healthy skin and connective tissues
• Supporting sleep and relaxation
• Helping the body produce creatine for muscle energy
• Supporting liver function and detoxification pathways

Glycine is especially important because every third amino acid in collagen is glycine, helping create collagen’s strong triple-helix structure.

Proline

Proline is another major amino acid found in collagen.

Its roles include:

• Supporting skin elasticity and firmness
• Helping maintain healthy joints and cartilage
• Assisting tissue repair and wound healing
• Supporting the structure of collagen fibres

The body can make proline itself, but additional dietary intake may help support collagen production.

Hydroxyproline

Hydroxyproline is one of collagen’s signature amino acids and is rarely found in large amounts in other proteins.

It helps:

• Stabilise collagen structure
• Support skin hydration and elasticity
• Maintain healthy connective tissue
• Support joint and bone health

Hydroxyproline is often used in scientific research as a marker for collagen content because it is so closely linked to collagen itself.

Alanine

Alanine helps support:

• Energy production
• Muscle function
• Recovery after exercise
• Blood sugar metabolism

It also contributes to the body’s ability to use proteins efficiently.

Arginine

Arginine is involved in:

• Blood flow and circulation
• Wound healing
• Immune function
• Exercise performance

It also helps the body produce nitric oxide, which supports healthy blood vessels.

Glutamic Acid

Glutamic acid supports:

• Nervous system function
• Gut health
• Protein metabolism
• Cellular energy production

It is an important amino acid involved in many metabolic processes.

Lysine

Lysine is an essential amino acid, meaning it must come from the diet.

It plays a key role in:

• Collagen formation
• Calcium absorption
• Tissue repair
• Immune support

Lysine works alongside vitamin C to support the body’s natural collagen production.

Leucine, Isoleucine and Valine

These are known as branched-chain amino acids (BCAAs).

They help support:

• Muscle protein synthesis
• Exercise recovery
• Muscle maintenance
• Energy production during exercise

Although collagen is not considered a complete protein for muscle building on its own, these amino acids still contribute to overall protein intake.

Threonine

Threonine contributes to:

• Healthy skin and connective tissues
• Protein balance in the body
• Gut lining support
• Immune function

It is another amino acid involved in collagen and elastin production.

Histidine

Histidine helps support:

• Tissue growth and repair
• Immune function
• Production of histamine
• Nerve protection

It is considered an essential amino acid.

Why Is Collagen’s Amino Acid Profile Important?

Collagen’s amino acid composition is what makes it unique.

Many traditional protein sources focus heavily on muscle-building amino acids, whereas collagen provides targeted support for connective tissues throughout the body.

This may help support:

• Skin elasticity and hydration
• Joint comfort and mobility
• Healthy hair and nails
• Bone strength
• Tendons and ligaments
• Muscle recovery
• Healthy ageing

As we age, the body’s natural collagen production declines. This process can begin as early as our mid-20s.

Factors such as:

• Sun exposure
• Smoking
• Stress
• Poor diet
• Lack of sleep
• Menopause
• Intense exercise

can also contribute to collagen breakdown.

Supplementing with our collagen may help provide the amino acids the body needs to support collagen formation and maintenance.

Collagen and Skin Health

One of the most popular reasons people use our collagen is for skin support.

Collagen is a major structural component of the skin and helps maintain:

• Firmness
• Elasticity
• Hydration
• Smoothness

Research suggests collagen peptides may help support skin elasticity and hydration by providing the amino acids needed for collagen synthesis.

Glycine, proline and hydroxyproline are especially important for maintaining the skin’s structural integrity.

Collagen and Joint Support

Collagen is also found in cartilage, tendons and ligaments.

As collagen levels decline with age and activity, joints may feel stiffer or less supported.

The amino acids in collagen help support connective tissues that are important for:

• Joint comfort
• Mobility
• Flexibility
• Recovery after exercise

This is why our collagen is popular with active individuals and those looking to support healthy ageing.

Is Collagen a Complete Protein?

Collagen is not considered a “complete protein” because it contains low amounts of some essential amino acids, such as tryptophan.

However, this does not reduce its value.

Collagen offers a specialised amino acid profile that complements other protein sources within a balanced diet. Rather than replacing dietary protein, collagen works alongside it to provide targeted support for connective tissues.

How to Support Natural Collagen Production

In addition to collagen supplementation, there are several ways to support the body’s natural collagen production:

• Eat enough protein
• Include vitamin C-rich foods such as berries, kiwi and citrus fruits
• Avoid smoking
• Protect skin from excessive sun exposure
• Prioritise sleep and recovery
• Manage stress levels
• Stay hydrated

Vitamin C is especially important because it acts as a cofactor in collagen synthesis.

Final Thoughts

Collagen is much more than just a beauty supplement.

Its unique amino acid profile provides important building blocks that support the body’s connective tissues, skin, joints, muscles and overall wellbeing.

Amino acids such as glycine, proline and hydroxyproline make our collagen different from many other protein sources and help explain why collagen supplementation has become so popular.

By understanding the amino acids found in collagen and their roles in the body, it becomes easier to see how collagen can support healthy ageing, recovery and everyday wellness.

FAQ

These products are not intended to diagnose, treat, cure or prevent any disease. If you have a medical condition, or are pregnant or breastfeeding, we recommend consulting your healthcare professional before use.