A few small clinical studies suggest that collagen supplements can reduce pain in people with knee osteoarthritis. However, the improvements are modest and benefits may take three to five months to appear.yacobchuk/iStockPhoto / Getty Images
Judging by the multitude of collagen supplements available – from capsules and gummies to liquids and powders – collagen is big business.
And no wonder. The sought-after ingredient is credited for rejuvenating skin and smoothing wrinkles, promoting nail and hair growth, easing joint pain, strengthening bones, even building muscle.
But do collagen supplements deliver on their promises? Here’s what the science says.
What is collagen?
The most abundant protein in the body, collagen is the main component of connective tissue, which provides structure and support to other body tissues.
Collagen-rich connective tissue keeps our skin supple and elastic, strengthens bones, supports joints and tendons and maintains flexible blood vessels. It’s also an important component of skeletal muscle.
There are different types of collagen in the body. Most common is Type I, found in bones, ligaments, tendons and skin. Type II comes from cartilage and joints, while Type III collagen is found in skin and blood vessels.
With age, our body produces less collagen, making us prone to wrinkles, sore joints and weakened bones. Cigarette smoking, excessive sun exposure, heavy alcohol intake and lack of sleep accelerate collagen loss.
Supplementing with collagen, then, can seem like an appealing way to slow aging.
About collagen supplements
Collagen supplements are made from animal parts, such as bovine or chicken bones and skins or fish scales. They’re sold as hydrolyzed collagen or collagen peptides, which are smaller units of collagen that are easier for the body to absorb.
Collagen peptides contain the same protein-building blocks (amino acids) as the animal products they’re derived from. Some supplements may also contain other ingredients thought to benefit skin or joint health.
Are collagen supplements beneficial?
It’s important to note that many studies are funded, at least partially, by companies that manufacture collagen, which could potentially bias the results.
Skin aging
Supplementing with four to 10 g of collagen daily for four to 12 weeks seems to benefit skin health, especially in older women. A 2021 review of 19 randomized clinical trials conducted in 1,125 women, for example, concluded that hydrolyzed collagen was beneficial for skin hydration and elasticity (e.g., wrinkles and roughness).
The research is unclear, however, whether collagen supplements reduce skin wrinkles to a cosmetically significant degree.
Joint health
A few small clinical studies suggest that collagen supplements can reduce pain in people with knee osteoarthritis. However, the improvements are modest and benefits may take three to five months to appear.
Preliminary research also suggests that taking five to 10 g of collagen daily for six months can modestly ease joint pain during exercise in student athletes. In adults 50 and older, collagen supplements don’t appear to reduce joint pain.
A combination product containing fish collagen, chondroitin, glucosamine and L-carnitine, however, was shown to lessen joint pain in older adults. But it was unclear if the benefit was due to collagen, the other ingredients, or the combination.
Bone health
There’s conflicting evidence that collagen supplements protect against bone loss in postmenopausal women with low bone density.
In one study, taking collagen along with calcium and vitamin D for one year had no effect bone density compared to taking calcium and vitamin D alone. Another study found that 10 g of collagen taken daily for 12 months modestly increased bone density of the spine compared to placebo.
Muscle-building
A few small studies suggest that collagen supplements, combined with resistance training, may increase muscle strength and lean muscle in premenopausal women, young men and older men with sarcopenia (age-related muscle loss) compared to a placebo.
However, when compared to whey protein, research has shown collagen to be ineffective at increasing muscle protein synthesis in young adults and in older women. Not surprising, since collagen is a low quality protein; it’s made up mostly of non-essential amino acids, ones the body can make on its own.
Collagen is also low in leucine, an essential amino acid that is key for stimulating muscle protein synthesis. (The body can’t make essential amino acids; they must come from diet.)
Bottom line
Supplementing with collagen seems to improve signs of aging skin, but don’t expect your wrinkles to disappear. Taking collagen may also modestly reduce joint pain people with knee osteoarthritis and in young athletes.
There’s scant evidence, though, that collagen supplements counteract bone loss. And if your goal is to gain muscle, don’t trade in your whey (or pea) protein for a collagen supplement.
Collagen supplements are considered safe and without adverse effects in doses up to 10 grams.
Leslie Beck, a Toronto-based private practice dietitian, is director of food and nutrition at Medcan. Follow her on Twitter @LeslieBeckRD
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