Collagen is the most abundant protein in the human body, acting as a fundamental structural component for our skin, bones, muscles, tendons, and ligaments. It provides the framework that helps hold tissues together. Scientists have identified at least 28 different types of collagen in the human body, each serving a unique purpose. Among these, Type I and Type III are prominent and frequently discussed when it comes to dietary supplements and general education.
If you have looked into adding a collagen supplement to your routine, you may have come across the topic of type 1 vs type 3 collagen. Understanding the general distinctions between these two types in the human body can provide helpful context, even though dietary collagen is digested into amino acids and peptides rather than being absorbed whole. While they share similarities and often work together in the body, they have distinct roles in human tissues.
In this guide, we will explore the characteristics of Type I and Type III collagen in the body, examine how they function, and review what the current evidence says about dietary collagen supplementation.
What is Type I Collagen?
Type I collagen is the most abundant type of collagen in the human body, accounting for roughly 90% of our total collagen stores. It is characterized by densely packed fibers that provide structural strength. This makes it a primary component of our skin, bones, tendons, cartilage, connective tissue, and teeth.
In the skin, Type I collagen is a key structural element. As we age, the body's natural production of collagen begins to decline. This gradual decrease is a contributing factor to the visible signs of aging. However, when it comes to dietary supplementation, the evidence is mixed. A 2025 meta-analysis of 23 randomized trials found apparent improvements in pooled analyses for skin aging, but non-industry-funded studies and high-quality studies showed no significant benefit. The authors concluded that there is currently no clinical evidence supporting collagen supplements to prevent or treat skin aging.
Beyond the skin, Type I collagen is a component of bones and tendons. Tendons, which connect muscles to bones, rely on collagen for structure. The organic matrix of our bones is also primarily composed of Type I collagen. Research on collagen supplementation for joint function has been explored, but results are product-specific and often limited by study quality. A 2023 meta-analysis of four randomized trials in people with knee osteoarthritis reported less pain versus placebo, but all included trials were considered high risk of bias, and the authors called for better trials. A 2025 systematic review reported promising joint outcomes but emphasized heterogeneity that limits generalizability. These findings do not prove that a given finished product will produce the same result, and collagen supplements are not intended to treat osteoarthritis or repair joints.
What is Type III Collagen?
While Type I collagen is known for its structural strength, Type III collagen is often associated with flexible tissues. It is the second most abundant type of collagen in the human body and is frequently found working alongside Type I collagen. Type III collagen consists of reticular fibers, which form a supportive mesh-like network within tissues.
Type III collagen is primarily found in tissues that require a degree of flexibility. This includes the skin, blood vessels, and internal organs such as the lungs, liver, and intestines. In the skin, Type III collagen is part of the extracellular matrix. The skin of infants and young children contains a higher proportion of Type III collagen compared to adults.
In the cardiovascular system, Type III collagen is a component of blood vessels, and it is also part of the structure of various internal organs. During the body's natural tissue repair processes following an injury, Type III collagen is often synthesized early on, forming a temporary framework that is later replaced by Type I collagen.
Type 1 vs Type 3 Collagen in the Body
When comparing type 1 vs type 3 collagen in human tissues, the primary distinction relates to their structural roles. Type I collagen provides a rigid framework for bones, tendons, and skin. Type III collagen is found in dynamic tissues like blood vessels, organs, and the skin.
Despite these differences in the body, it is important to recognize that Type I and Type III collagen are not mutually exclusive. They are often found together, working synergistically to maintain the structure of connective tissues. However, it is crucial to understand that consuming a specific type of collagen does not direct it to a specific tissue. Dietary collagen is digested into amino acids and peptides, and human pharmacokinetic findings do not prove that consuming a specific collagen type guarantees a specific clinical outcome.
Understanding Collagen Sources and Labels
When shopping for a collagen supplement, you will typically encounter sources like bovine (beef) and marine (fish). Bovine hide is typically rich in type I collagen. However, it is important to read product labels carefully. Some products specify the types of collagen they contain, while others do not. For example, the current Mobility+ Supplement Facts label does not specify collagen types.
Additionally, while some sources suggest that vitamin C is required for the body's endogenous collagen biosynthesis, this does not establish that vitamin C must be taken at the same moment as a collagen supplement, or that pairing it with a specific product improves outcomes.
When considering collagen supplementation, it is helpful to consult authoritative sources. The Harvard Nutrition Source notes that collagen studies often have industry ties, products vary, dietary collagen is digested, and large high-quality trials are needed. Cleveland Clinic provides additional context on dietary collagen and the limits of supplement claims.
Mobility+ Product Information
If you are considering a collagen supplement, Mobility+ is an unflavored hydrolyzed bovine-hide collagen-peptide powder. The front label states it "Supports Joint Comfort, Mobility & Healthy Connective Tissue" and notes it is "Grass-Fed" and "Unflavored."
The current product label facts are as follows:
- one 280 g container
- 14 servings
- serving size one 20 g scoop
- 70 calories
- 18 g protein
- 26 mg calcium (2% DV)
- 20 g hydrolyzed bovine-hide collagen peptides
- unflavored
- front label says grass-fed
Suggested use: adults mix one scoop with 8–10 oz (237–296 mL) beverage in a shaker cup or blender.
Important Safety Information
Mobility+ is bovine-derived and is not suitable for people avoiding bovine products. People with food allergies or dietary/religious restrictions should review the label and contact the manufacturer if needed.
Do not exceed the recommended dose. Consult a physician if pregnant, nursing, under 18, or if you have a medical condition. Review supplements with a clinician if taking medicines or planning surgery. People who must limit protein because of gout, kidney disease, or another clinician-directed diet should ask their clinician before using a concentrated protein supplement. Stop use and seek advice for an adverse reaction.
Keep out of reach of children. Do not use if the safety seal is damaged or missing. Store in a cool, dry place. The product is sold by weight, not volume; settling may occur.
Want to learn more before deciding whether collagen supplementation fits your routine? Explore the Mobility+ benefits guide.
References
- Effects of Collagen Supplements on Skin Aging: A Systematic Review and Meta-Analysis of Randomized Controlled Trials
- Analgesic efficacy of collagen peptide in knee osteoarthritis: a meta-analysis of randomized controlled trials
- The Effects of Type I Collagen Hydrolysate Supplementation on Bones, Muscles, and Joints: A Systematic Review
- Harvard T.H. Chan School of Public Health: Collagen
- Cleveland Clinic: The Best Way You Can Get More Collagen
*These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.