What is the most common collagen in the human body?

December 23, 2025 •

4 min read

Comprising approximately 90% of the body's total supply, Type I collagen is the most common collagen, forming the primary structural framework for skin, tendons, and bones. This robust fibrous protein provides unparalleled tensile strength and elasticity to various connective tissues, making it fundamental to overall human health.

Quick Summary

An overview of Type I, the most abundant collagen in the human body, detailing its function in supporting skin, bones, and connective tissues. Explains the differences between the five most common collagen types, their bodily distribution, and how they contribute to structural integrity and health.

Key Points

Type I is Most Common: Type I collagen is the most abundant type in the human body, accounting for approximately 90% of the total supply.
Supports Vital Structures: Its primary role is to provide structure, strength, and elasticity to essential tissues like skin, bones, tendons, ligaments, and organs.
Critical for Bone Health: As the main component of bone's organic matrix, Type I collagen is essential for bone strength and mineralization.
Aids Skin Elasticity: The dense fibers of Type I collagen are crucial for maintaining youthful skin, helping to reduce the appearance of wrinkles.
Different Types Serve Specific Needs: While Type I is dominant, Type II is key for cartilage and joint cushioning, and Type III supports skin elasticity and blood vessels.
Supplementation Varies by Source: Bovine and marine sources primarily contain Type I and Type III collagen, while chicken sources are rich in Type II.

Understanding the Most Common Collagen: Type I

Among the 28 identified types of collagen, Type I is unequivocally the most common collagen, making up the vast majority of the body's total collagen content. This prevalence is due to its critical role as the primary structural protein in almost all connective tissues, providing the foundation for strength and elasticity. The structure of Type I collagen is a dense, triple-helical fibril, which is remarkably strong—gram for gram, it's stronger than steel.

This abundant protein is found in numerous parts of the body, including skin, bones, tendons, ligaments, organs, and the vascular system. Its widespread presence highlights its importance in maintaining the body's structural integrity and function. As we age, the body's natural production of collagen, particularly Type I, begins to decline. This reduction is a contributing factor to the visible signs of aging, such as a loss of skin firmness and the emergence of wrinkles, as well as the progressive weakening of bones and joints.

The Importance of Collagen for Bodily Functions

Collagen is more than just a beauty-related molecule; it is a fundamental protein that supports a multitude of physiological functions. Here are some of its key roles:

Skin Health and Elasticity: Collagen provides the skin with its structural scaffolding. A robust network of collagen fibers is essential for maintaining skin's elasticity, hydration, and overall firmness, which helps to minimize the appearance of fine lines and wrinkles.
Bone Strength: The organic part of bone is primarily composed of Type I collagen. It forms a matrix upon which minerals like calcium and phosphorus are deposited, giving bones their rigid structure and strength.
Connective Tissue Support: As the main component of tendons and ligaments, collagen is vital for connecting bones and muscles, allowing for smooth and stable movement.
Wound Healing: Collagen plays a crucial role in the body's repair processes by attracting new skin cells to wound sites, which aids in tissue regeneration and repair.
Organ Protection: Many internal organs are surrounded and supported by a protective covering of collagen, which ensures their proper structure and function.

Comparing the Main Collagen Types

While Type I is the most common, other types of collagen play equally important, specialized roles in the body. Understanding these differences can help inform decisions regarding dietary supplements or targeted health approaches.


Feature	Type I Collagen	Type II Collagen	Type III Collagen
Bodily Location	Skin, bones, tendons, ligaments, organs, blood vessels	Cartilage, specifically hyaline cartilage in joints	Skin, muscles, blood vessels, organs (often co-exists with Type I)
Primary Function	Provides tensile strength, elasticity, and structural support	Forms elastic cartilage to cushion and support joints	Contributes to skin elasticity, blood vessel integrity, and muscle structure
Composition	Dense, robust, and tightly packed fibers	Looser, gel-like structure, providing flexibility and cushioning	Forms finer, delicate fibers known as reticular fibers
Supplement Source	Bovine, Marine, Porcine	Chicken Sternum Cartilage	Bovine, often included with Type I
Common Association	Anti-aging skincare, bone strength, hair, and nail health	Joint pain relief, arthritis support, cartilage repair	Skin elasticity, gut health, cardiovascular health

Beyond the Most Common Types

Beyond the well-known Types I, II, and III, numerous other collagen types exist, each with a specific function. For instance, Type IV collagen is a primary component of the basement membrane, a thin layer that provides structural support to epithelial cells and acts as a filter in the skin and kidneys. Type V collagen is found in hair, some skin layers, and the placenta, contributing to tissue strength and hair thickness. This diversity highlights the incredible complexity of collagen and its central role in the human body's overall architecture.

Sourcing Collagen for Supplementation

For those seeking to supplement their natural collagen production, several sources are available. Bovine and marine collagen are popular choices for providing Type I and Type III peptides, supporting skin, hair, and bone health. For targeted joint support, supplements often utilize chicken collagen, which is rich in Type II collagen. The body's ability to absorb collagen is dependent on it being broken down into smaller peptides, a process known as hydrolysis. A balanced diet rich in protein and vitamin C, however, is essential for supporting the body's natural collagen synthesis.

Conclusion

In summary, Type I is the most common collagen, acting as the fundamental structural protein that provides strength and elasticity to the skin, bones, and connective tissues throughout the body. While other collagen types perform specialized roles, Type I's prevalence underscores its foundational importance. Understanding the different types, their functions, and their sources empowers individuals to make informed decisions about nutrition and supplementation to support their body's structural health. The decline of collagen with age is a natural process, but with the right knowledge, it is possible to support your body's continued structural integrity.

Frequently Asked Questions

The primary function of Type I collagen is to provide structural integrity and tensile strength to connective tissues like skin, bones, tendons, and ligaments. It helps maintain the body's overall framework and durability.

As collagen levels decline with age, the body may experience a loss of skin elasticity leading to wrinkles, weaker bones, and decreased flexibility in tendons and ligaments. This is a natural part of the aging process.

Type I collagen forms thick, dense fibers that provide tensile strength to tissues, while Type III collagen creates a finer, more elastic network that provides flexibility. They often work together, particularly in the skin and blood vessels.

Both marine (fish) and bovine (cow) collagen are excellent sources of Type I collagen. The choice often depends on dietary preferences or potential allergies, as marine collagen may offer higher bioavailability and absorption.

Collagen supplements do not directly replace natural collagen. Instead, they provide the body with the necessary amino acid building blocks (peptides) that can help stimulate the body's own collagen production.

Type II collagen is primarily found in elastic cartilage, which is a connective tissue that provides cushioning and support for joints. Supplements targeting joint health often contain Type II collagen.

To support natural collagen production, consume a well-balanced diet rich in protein and vitamin C. Foods like chicken, fish, eggs, citrus fruits, and leafy greens provide the necessary amino acids and nutrients.