A collagen overview: From science to supplements

May 7, 2024 - By Kelsey Butler, MS, RDN

Editor’s note: This is an article in our monthly series, Healing Bites, which explores the healing properties of food.

Collagen has surged in popularity across health and wellness landscapes, touted for its purported benefits ranging from enhanced skin elasticity to improved joint health. As this trend continues to gain momentum, it will be important for health and wellness professionals to delve deep into the science and claims surrounding collagen to offer sound, evidence-based advice to their clients, patients and consumers.

By exploring both the hype and the substantiated benefits of collagen, health and wellness professionals and dietitians can better navigate client consultations and recommendations, ensuring that their guidance is informed by current trends and grounded in rigorous scientific understanding. This comprehensive approach will enable dietitians to effectively address clients’ growing curiosity and concerns about collagen and its role in health and wellness.

Collagen 101

Collagen, the predominant protein in the human body, is integral to the structural integrity of skin, bones, tendons and cartilage. It functions primarily to provide tensile strength and elasticity, thereby pivoting in tissue repair and structural support. The body synthesizes collagen from various amino acids, primarily glycine, proline and hydroxyproline, derived from dietary intake and endogenous production.

The body contains several types of collagen, with types I, II and III being the most common:

• Type I collagen: This type is predominantly found in skin, bone and connective tissues and is essential for skin elasticity and wound healing.
• Type II collagen: Located mainly in cartilage, it’s crucial for joint health and resilience.
• Type III collagen: Supports the structure of muscles, organs and arteries and often works in conjunction with Type I.

As aging progresses, collagen synthesis naturally declines, leading to the typical signs of aging, such as increased skin laxity and joint discomfort. External factors like UV exposure, smoking and high-sugar diets can exacerbate this decline, compounding the degenerative effects on collagenous tissues.

For health and wellness professionals, a deep understanding of collagen’s biochemistry and its systemic roles is crucial when assessing the validity of collagen supplementation claims and guiding patients, clients and consumers in evidence-based dietary strategies to support collagen production. This foundational knowledge enables dietitians to critically evaluate emerging research and trends related to collagen and its health implications.

Sources of collagen

Understanding the various sources of collagen is crucial for dietitians when advising clients on how to incorporate collagen into their diets naturally or when selecting supplements. Here’s a detailed look at natural food sources of collagen and the factors affecting collagen production in the body:

Natural food sources

• Animal products: The richest natural sources of collagen are found in animals’ connective tissues and bones. Foods like bone broth, chicken skin, pork skin and beef are particularly high in collagen. Cooking methods that slow-cook these parts (like stewing or braising) help release collagen, making it more digestible.
• Fish and shellfish: The skins and bones of fish and shellfish are excellent sources of marine collagen. This highly bioavailable protein is often used in supplements because it is more easily absorbed by the body.
• Dairy and eggs: While not as rich in collagen as connective tissues, these contain the necessary amino acids, particularly glycine and proline, that help form collagen in the body.

Supporting collagen production

Nutrients that enhance collagen synthesis:

• Vitamin C: An essential cofactor in collagen synthesis, found abundantly in citrus fruits, strawberries, bell peppers and broccoli.
• Zinc: Activates proteins essential for collagen synthesis. Good sources include beef, lamb, pumpkin seeds and lentils.
• Copper: Involved in forming collagen and elastin, found in organ meats, sesame seeds, cocoa powder and cashews.
• Collagen supplements: Collagen supplements typically come in hydrolyzed collagen (also known as collagen peptides), which is easier for the body to absorb. These supplements can be derived from various sources, including bovine (cow), porcine (pig), chicken and marine (fish) sources, each varying slightly in their type of collagen and specific amino acid composition.

When advising clients, dietitians should consider both dietary preferences and potential allergens. For instance, individuals allergic to fish should avoid marine collagen supplements. Furthermore, vegetarians or vegans who may not consume traditional sources of collagen can focus on increasing their intake of the necessary amino acids and nutrients that support collagen production in the body.

Research on collagen

The growing popularity of collagen supplements has been paralleled by an increase in scientific research exploring their potential health benefits. Here’s a closer look at what the current body of research suggests regarding collagen’s impact on various aspects of health:

Skin health

A 2023 systematic review analyzed 11 studies and found that collagen supplementation significantly improved skin elasticity, hydration and dermal collagen density. The study suggests that collagen peptides facilitate the skin’s natural production processes, which may help in slowing signs of aging.

Joint health

Research in “Nutrients” from 2023 indicated that collagen hydrolysate could be beneficial for osteoarthritis patients. It showed a significant improvement in joint pain and function over time. This aligns with the theory that collagen supplementation might contribute to joint cartilage regeneration and support overall joint health.

Bone density

A 2018 randomized control study found that collagen supplementation in postmenopausal women led to a statistically significant increase in bone mineral density compared to a placebo. The collagen appeared to help decrease bone breakdown, suggesting potential as a supportive treatment for osteoporosis.

Gut health

Preliminary studies, such as this 2022 study, have begun to explore collagen’s role in gut health, particularly its potential to support the integrity of the gut barrier. These studies suggest collagen might have a role in managing conditions like inflammatory bowel disease, though more research is needed.

Cardiovascular health

A 2023 meta-analysis found that collagen peptide supplements were associated with reduced systolic blood pressure and improved blood lipid profiles in healthy adults, indicating potential heart health benefits.

Health and wellness professionals must critically evaluate the evidence supporting collagen supplements, recognizing the variability in study designs, populations and outcomes. While the research is encouraging, it’s important to note that many studies are industry-funded, which could influence results. Dietitians should consider these factors when discussing collagen supplementation with clients, ensuring recommendations are based on unbiased, comprehensive research analysis. Staying informed about ongoing studies will help dietitians provide the most current and scientifically grounded advice.

Myths and facts around collagen

The popularity of collagen supplements has spawned numerous claims and myths, particularly propagated through social media and marketing efforts. As dietitians, you may need to address these myths with evidence-based facts to ensure clients are well-informed. Here’s a closer look at some prevalent myths and the realities that debunk them:

Myth: Collagen supplements reverse skin aging and eliminate wrinkles.

Fact: Research, such as studies published in the Journal of Drugs in Dermatology, indicates that collagen can improve skin elasticity and hydration, which may reduce the appearance of fine lines and wrinkles. However, it does not completely reverse skin aging or eliminate wrinkles. The improvements are generally modest and should be considered part of a broader skincare and health maintenance regimen.

Myth: Consuming collagen will directly rebuild collagen in targeted areas like joints and skin.

Fact: When ingested, the digestive system breaks down collagen peptides into amino acids and then absorbed into the bloodstream. The body uses these amino acids where needed, which may not necessarily be the areas consumers are targeting with their supplementation. The process is more about supporting overall collagen synthesis and less about directing collagen to specific body parts.

Myth: All collagen products offer the same benefits regardless of the source or type.

Fact: The effectiveness of a collagen supplement can vary based on its origin (bovine, marine, porcine) and the type of collagen it contains (Type I, II, III, etc.). Different types have different amino acid compositions and may be more beneficial for certain conditions; for example, Type II collagen is often studied for joint health, while Type I is noted for skin health. Additionally, the processing method can affect the size and bioavailability of the produced peptides.

Myth: Collagen supplements are a necessary part of everyone’s diet.

Fact: Collagen supplementation is not essential for everyone. It should be considered when there is a specific therapeutic need or goal, such as improving skin hydration or joint function, and based on individual dietary intake and health assessment. For many people, adequate protein intake from a varied diet may be sufficient for supporting natural collagen production.

Dietitians must encourage clients to approach collagen supplementation with a critical mindset, evaluating the credibility of sources and the evidence behind claims, particularly those trending on social media. This ensures that clients rely on scientifically backed information and practical expectations when considering collagen as part of their health regimen.

Collagen plays a critical role in maintaining the structural integrity of various body tissues, and its popularity in the health and wellness industry continues to grow. As health and wellness professionals, it is important to understand collagen’s functions, sources and the research that supports its benefits and limitations. Dietitians can guide their clients through the complexities of collagen supplementation and natural intake by debunking myths, clarifying the facts and providing evidence-based recommendations.

FAQs

Can diet alone provide sufficient collagen for health benefits?

While certain foods are rich in collagen, such as bone broth, meats and fish, diet alone may not always provide enough collagen for specific health outcomes, like improved skin elasticity or joint health, especially as natural production decreases with age. In such cases, supplements might be beneficial.

What should be considered when recommending collagen supplements to clients?

Dietitians should assess individual needs based on age, health status and specific goals. Choosing high-quality collagen supplements, preferably those that have undergone third-party testing for purity and efficacy, is important. Consider any dietary restrictions, such as vegetarian or vegan preferences, which might affect the type of collagen supplement recommended.

Are there any side effects or risks associated with collagen supplementation?

Collagen supplements are generally considered safe for most people. However, some individuals may experience minor digestive side effects, such as feelings of fullness or heartburn. Starting with lower doses is crucial to monitor tolerance and adjust as needed.