Hydrolyzed collagen type 1 and 3 is a supplement made by breaking down collagen protein from animal sources (typically bovine hide or fish) into small peptide chains that your body can absorb efficiently. The “hydrolyzed” part refers to the manufacturing process, while “type 1 and 3” identifies the two specific forms of collagen included, which together account for the vast majority of collagen in your skin, bones, tendons, blood vessels, and organs.
What “Hydrolyzed” Actually Means
Collagen in its natural form is a massive protein with a molecular weight of 285 to 300 kilodaltons. That’s far too large for your gut to absorb intact. Hydrolysis uses enzymes to break apart the protein’s triple-helix structure, snipping the long chains into tiny peptide fragments weighing just 3 to 6 kilodaltons. That’s roughly 1/50th to 1/100th the size of the original molecule.
The process works in stages. First, heat denatures the collagen, unraveling its tightly wound structure from a triple helix into a loose, random coil. Then proteolytic enzymes cleave the bonds between amino acids, producing the small peptides sold as supplements. This enzymatic method is preferred over chemical hydrolysis (using strong acids or bases), which tends to leave behind high salt concentrations and a harsher final product.
Once hydrolyzed, the resulting peptides dissolve easily in water and are absorbed quickly. In both animal and human studies, blood levels of collagen-derived amino acids peak about one hour after ingestion.
Where Types 1 and 3 Work in Your Body
Type 1 collagen is the most abundant protein in the human body, making up about 90% of all collagen. It forms densely packed fibers that give structural strength to skin, bones, tendons, ligaments, and even the cornea. In your skin, type 1 constitutes 80 to 85% of the structural framework. In bone, it accounts for over 90% of the organic matrix, creating a scaffold where mineral crystals anchor to give bones their rigidity. Tendons are 60 to 80% type 1 collagen by dry weight, with fibers aligned in parallel bundles to handle high tensile loads.
What makes type 1 so versatile is that its fibers adapt to each tissue’s needs. In the cornea, the fibrils are tiny (about 20 nanometers across) and arranged in precise perpendicular layers to maintain optical transparency. In mature tendons, they’re much larger, around 500 nanometers, bundled tightly to resist pulling forces. In skin, they form an interlacing mesh rather than running in neat parallel lines, which helps skin stretch and rebound in multiple directions.
Type 3 collagen plays a different but complementary role. It’s found in blood vessel walls, the lining of internal organs (intestines, liver, lungs), muscles, and skin, where it makes up about 8 to 11% of the dermal structure. Type 3 often coexists with type 1 within the same fibers, and research in PNAS demonstrated that type 3 is essential for type 1 fibers to form correctly. Without type 3, collagen fibers in blood vessels, skin, and organs become irregular in size and poorly organized. Type 3 collagen essentially regulates the diameter of type 1 fibers, fine-tuning them to meet each tissue’s mechanical needs. It’s also critical for cardiovascular health: in the aorta, type 3 collagen between smooth muscle cells helps limit dangerous dilation of the vessel wall.
How Types 1 and 3 Differ From Type 2
Type 2 collagen serves a completely different tissue. It’s the primary collagen in cartilage, the cushioning material between joints. Supplements labeled “type 2” target joint cartilage specifically and are often derived from chicken sternum. Types 1 and 3, by contrast, support the broader structural system: skin firmness, bone density, tendon and ligament integrity, and organ structure. If your goal is skin, bone, or connective tissue support, types 1 and 3 are the relevant forms. If your concern is strictly joint cartilage, type 2 is more targeted.
What the Evidence Shows for Skin
A systematic review and meta-analysis found that oral collagen supplementation at doses ranging from 1 to 10 grams per day significantly improved both skin hydration and elasticity. The most common dose used across clinical trials was 4 grams per day, with a median of 3.5 grams. These aren’t dramatic overnight changes. Improvements in skin texture and hydration typically become noticeable within 4 to 8 weeks of daily use, as the skin’s natural turnover cycle needs time to incorporate the new building blocks.
What the Evidence Shows for Bones
A randomized, placebo-controlled trial in postmenopausal women found that 5 grams of collagen peptides per day significantly increased bone mineral density. Over the study period, bone density in the spine increased by nearly 3% and in the femoral neck (the most fracture-prone area of the hip) by 6.7%. In the placebo group, bone density actually declined by 1.3% and 1% in those same areas. Blood markers confirmed the mechanism: a bone formation marker (P1NP) rose significantly, indicating that new bone was actively being built. Collagen peptides have also been shown to increase gene expression related to type 1 collagen production, suggesting the supplements stimulate your body to make more of its own collagen.
Key Amino Acids and Common Sources
The three amino acids that define collagen are glycine, proline, and hydroxyproline. Hydroxyproline is particularly notable because it’s rare outside of collagen, which is why blood levels of hydroxyproline serve as a reliable marker for collagen absorption in studies. These amino acids give collagen its ability to form tight, rope-like fibers that resist stretching.
Most type 1 and 3 supplements come from bovine (cow) hide or bones, though marine (fish skin and scales) versions are also widely available. Both sources provide types 1 and 3, though bovine is the more traditional and common option. Marine collagen tends to have slightly smaller peptide sizes, but both reach peak absorption at roughly the same timeframe.
Realistic Timelines for Results
Different tissues respond at different speeds, and setting expectations matters. Nails tend to respond first, with reduced peeling and breakage often visible within 2 to 4 weeks as the nail matrix picks up improved nutrient supply. Skin changes follow at the 4 to 8 week mark, showing up as smoother texture, better elasticity, and more even tone rather than a sudden transformation. Hair requires the most patience. Because hair grows in cycles with long dormant phases, visible changes like thicker strands, reduced shedding, or fuller growth typically take 3 to 6 months of consistent supplementation.
Side Effects and Safety
Hydrolyzed collagen is generally well tolerated, and most people experience no side effects. Mild digestive discomfort (bloating or a feeling of fullness) is the most commonly reported issue. However, collagen supplements are not entirely without risk. Fish-derived collagen can trigger immediate allergic reactions in people with fish allergies. There have also been rare case reports of more serious skin reactions linked to collagen supplement use, including one documented case of a severe drug-like eruption in a previously healthy patient. If you have known allergies to the source animal (bovine, fish, or shellfish), check the label carefully before starting any collagen product.