Mickie Cathers
Collagen is a leader in the supplements market, advertised as a boon to joint and bone health, and a remedy for aspects of aging such as dehydration, loss of skin elasticity, and wrinkles. But is collagen supplementation all it’s cracked up to be?
Background
Collagen, elastin, and hyaluronic acid are the main components of the skin and play an important role in maintaining its structure and hydration. Collagen is the primary protein structure of various connective tissues, responsible for structural organization, integrity, elasticity, and strength of skin. Skin collagen is produced by fibroblasts, which comprise three components of the extracellular matrix of the dermis: collagen fibers, elastic fibers, and proteoglycans. This collagen-rich extracellular matrix builds and repairs the structure of skin components.
About 30% of protein content in the body is made from collagen. Three amino acids—glycine, proline, and hydroxyproline—constitute collagen’s characteristic triple helix. An adequate amount of vitamin C, zinc, copper, and manganese in the body allows this triple helix to be formed.
Collagen production naturally declines as we age, leading to the characteristic signs of getting older such as wrinkles and dry or sagging skin as well as reduced bone strength. These changes, including dehydration, loss of elasticity, and a reduction in epidermal thickness are due to a decrease in the number of blood vessels in the skin, and a decline in fibroblast activity and enzymes involved in the posttranslational processing of collagen.
Is there a benefit?
Results from many studies over the years support the beneficial effects of collagen supplementation but emphasize that the source of collagen supplementation and duration of use affects its impact.
Campos and colleagues evaluated the scientific evidence regarding the beneficial effects of collagen consumption in the treatment of skin and orthopedic changes such as bone strength, density, and mass; joint stiffness and mobility; and reduction of pain associated with bone loss due to aging in a literature review published online in the April 2023 issue of Heliyon. Authors indicated that the literature revealed that collagen supplementation can be beneficial in the treatment of skin changes by reducing wrinkles, increasing skin elasticity, hydration, and firmness, and increasing collagen synthesis.
Hyaluronic acid, a glycosaminoglycan with the capacity to retain water molecules, is a key molecule involved in skin hydration. Oral administration of hydrolyzed collagen that includes rich proline and hydroxyproline was seen to encourage hyaluronic acid production in the dermal fibroblast cells. The hydrolyzed collagen works in two ways: either providing amino acids for the synthesis of collagen and elastin fibers or stimulating the production of new collagen, elastin, and hyaluronic acid by binding bioactive peptides to fibroblast membrane receptors in the dermis.
Hydrolyzed collagen has also been shown to contain biologically active peptides that are able to reach joint tissues and promote cartilage production.
Reviewed studies also showed that the use of collagen in the treatment of orthopedic issues increased bone strength, density, and bone mass and decreased extracellular matrix degradation. Collagen inhibited inflammatory cytokines, and improved joint stability, functional capacity, stiffness/mobility, and muscle recovery. Some studies also reported reduced pain and the finding that collagen use mitigated markers of joint cartilage degradation.
Similarly, Pu and colleagues reviewed 26 randomized clinical trials to assess the effects of hydrolyzed collagen supplementation on skin hydration and elasticity published in a May 2023 systematic review and meta-analysis in Nutrients. The studies involved 1,721 patients taking collagen supplementation from 2 to 12 weeks. Collagen sources included fish, beef, chicken, and pork. Skin hydration levels were assessed using a noninvasive tool called a corneometer that measures the amount of water present in the top layer of skin through a high-frequency electric current. Skin elasticity was confirmed using cutometry, a noninvasive technique that applies controlled pressure to a small area of skin and measures the resulting deformation.
Results showed significant improvement in both skin hydration and elasticity from hydrolyzed collagen originating from fish, beef, chicken, pork, and unknown sources compared to the placebo group. Subgroup analyses revealed that effects of collagen supplementation on skin hydration varied based on the source of collagen and duration of supplementation. Collagen originating from fish had the strongest effect and chicken was seen to have the weakest effect. Beneficial effects were significant after 8 weeks or more of collagen supplementation.
Dosage and availability
Collagen supplements are available as gels, liquids, powders, and capsules. The supplement can be added to beverages, oatmeal, yogurt, smoothies, and desserts. On store shelves and online, collagen can be found in topical creams, moisturizers, and serums. Dosages vary in clinical studies with most study participants seeing benefits using 2.5 g/day to 15 g/day for 8 weeks or longer.
What to tell your patients
Collagen supplements are not associated with adverse effects and are generally regarded as safe to use. Encourage patients to read the labels and understand the potential risks of supplements mixed with other ingredients such as herbs or added vitamins.
It’s worth noting that the body makes collagen naturally and supplementation isn’t necessary when eating a balanced diet consisting of adequate protein, fruits, vegetables, nuts, seeds (especially hemp, pumpkin, and cashews); and specific sources of the amino acids commonly found in collagen, such as bone broth, eggs, dairy, legumes, tofu, spirulina, red meat, poultry, pork, and fish. ■