What Is Hydrolyzed Collagen?

Hydrolyzed collagen (HC) is an anti-aging supplement. It is said to reduce wrinkles, alleviate joint pain, improve bone health, promote weight loss, and more. 

Collagen contains amino acids, the building blocks of protein. The hydrolyzed form of collagen, also known as collagen peptides or collagen hydrolysate, is easily absorbed into the bloodstream.

This article discusses hydrolyzed collagen, its benefits, and potential side effects. It also explains what to look for when buying hydrolyzed collagen and how to take it.

Understanding Collagen and Hydrolyzed Collagen

A key protein produced in the body, collagen is found primarily in the skin, bones, cartilage, tendons, and teeth. It plays a critical role in the structure and function of the body's cells and tissues, such as blood vessels, cornea, gums, and scalp. And it promotes wound healing and bone repair.

With age, collagen production declines. And some people take hydrolyzed collagen supplements in an effort to help restore collagen that has been depleted.

The collagen found in supplements can be extracted from several different animal sources, including cows and pigs.

Recent research has shown good properties of HC found in skin, scales, and bones of marine sources, such as fish, and invertebrates such as shellfish, jellyfish, or sponges. And some manufacturers also extract collagen from algae. Alternative sources of HC that have shown great functionality include chicken legs and feet and a frog species found in China and Mongolia.

Health Benefits of Hydrolyzed Collagen

Health benefits of collagen supplements have been reported.

Collagen research has specifically focused on:

• Skin anti-aging
• Bone and joint health
• Wound healing
• Body composition

There is less research on the effects of collagen on weight loss, nail growth, heart health, and eye health.

Skin Health

Collagen makes up around 70% to 75% of our skin, the largest organ in the body, which protects us from external damage, helps regulate temperature and performs other critical bodily functions. As we age, collagen in the skin’s inner layer can deplete, leading to dryness, loss of elasticity, and lines and wrinkles.

Recent studies have shown oral HC supplements to be effective in slowing down signs of skin aging.

In 2017, Genovese et al examined 120 healthy subjects who ingested a nutricosmetic formulation containing 50 milliliters (mL) of HC or placebo. An analysis revealed that the nutricosmetic formulation produced an improvement in the structure of the epidermis.

The structure and stratification of collagen fibers within the dermis were also improved. In a post-study questionnaire, 95% of the subjects agreed that their skin was more hydrated, more elastic (91.6%), stronger (81.7%), and thicker (91.7%).

Another study, an eight-week investigation of 114 healthy patients assigned female at birth, showed that consumption of collagen demonstrated a significant reduction in eye wrinkles compared with placebo. Subjects also showed increased procollagen type 1 (65%) and elastin content (18%).

Finally, a 12-week study that included 106 White people assigned female at birth demonstrated that oral consumption of collagen derived from fish led to a significant 8.83% increase in collagen density versus 0% with placebo, and a 31.2% reduction of collagen fragmentation versus increased fragmentation with placebo.

While these studies offer some promising results, the use of collagen supplements in dermatology has been controversial, due to the lack of large-scale randomized controlled trials (RCTs). Furthermore, some people who use collagen-based products for dermatologic purposes may have unrealistic expectations about results.

Joint and Bone Health

To date, there are more than 60 studies about HC efficacy in reducing collagen damage, osteoarthritis (joint pain and erosion), and osteoporosis (bone density loss). These results, as well as a high level of tolerance and safety, can make taking HC appealing for long-term use in bone and joint degenerative diseases.

Recent findings include a study of 51 postmenopausal individuals assigned female at birth with osteopenia (bone loss) that found that adding HCs to calcium and vitamin D supplements may enhance bone metabolism.

In another study of 250 subjects with osteoarthritis of the knee, participants were given 10 grams of HC daily for six months. After the study, there was a significant improvement in knee joint comfort, based on both visual analog and pain scale assessments. Subjects with the greatest joint deterioration benefited the most.

Wound Treatment

Recent findings show that HC-based supplements could significantly improve wound healing and circulating prealbumin, and clinically reduce time spent in the hospital for burn patients. Low prealbumin found in burn patients at admission is predictive of a longer hospital stay.

In a 2019 pilot clinical trial, 31 adults assigned male at birth with 20% to 30% burns over their total body surface area were randomly assigned to receive either a collagen-based supplement or placebo for four weeks.

Serum prealbumin, rate of wound healing, and length of hospital stay were assessed at baseline, and at the end of weeks two and four. Researchers found that serum prealbumin was significantly higher at week two and week four in the collagen group compared to the control group.

Changes in pre-albumin concentration were also significantly higher in the collagen group at weeks two and four. Hospital stay was clinically, but not statistically, lower in the collagen group compared to the control group.

Another investigation tested the effect of collagen supplementation on the treatment of pressure ulcers (stages II and IV) in 89 long-term care residents. Patients treated with collagen demonstrated statistically significant wound healing, as measured by the pressure ulcer scale for healing (PUSH) compared with placebo (score of 3.55±4.66 vs 3.22±4.11).

Body Composition

Although there are few studies conducted on humans about the effects of collagen peptides on body fat reduction, early results show promise.

A 2019 Korean study investigated the efficacy and tolerability of skate skin collagen peptides (SCP) on reducing body fat in overweight adults. Ninety healthy volunteers with a mean body mass index (BMI) of 25.6 ± 1.9 kg/m² were assigned to the intervention group, which received 2000 mg of SCP per day, or to the control group given a placebo for 12 weeks; 81 (90%) participants completed the study.

Changes in body fat were evaluated using dual-energy X-ray absorptiometry (DEXA scan). At the end of the trial, the percentage of body fat and body fat mass in the intervention group was significantly better than those of subjects in the control group. SCP was well tolerated, and no notable adverse effect was reported from either group.

A second study also showed positive results. In a cohort of 77 premenopausal individuals assigned female at birth, resistance training, in combination with collagen supplementation, induced a significantly higher increase in fat-free mass and hand-grip strength than resistance training paired with placebo supplementation.

In addition, there was a significantly higher loss in fat mass and a more pronounced increase in leg strength in the treatment group compared to the control group.

Side Effects and Precautions

HC’s high level of safety makes it appealing as an agent for long-term use. Still, some people may experience side effects, such as mild digestive issues.

Certainly, those allergic to fish or shellfish should avoid any products containing these ingredients, such as marine collagen. They are also not suitable for vegetarians or vegans since they contain animal by-products.

In addition, the FDA has issued warning letters to cosmetic companies that make unproven claims about their products or classify them as drugs, not cosmetics. These letters state that the products are being marketed with drug claims, indicating they are intended to treat or prevent disease or change the body’s structure or functions.

These have included claims that certain products increase the production of collagen and elastin, resulting in skin that is more elastic and firmer, with fewer wrinkles.

Finally, collagen supplements have not been tested for safety. This includes specific populations such as pregnant people, nursing parents, children, and those with medical conditions or who are taking medications.

How to Take Hydrolyzed Collagen

In most cases, collagen supplements are ingested orally, as a tablet, capsule, or in powder form. HC is frequently used as an ingredient in food supplements as well, as it has antioxidant and antimicrobial properties. It can also be consumed by eating bone broth or pork skin.

Depending on the condition being treated, recommended dosages can vary, from 2.5 grams to 30 grams per day.