Fact or fiction: do collagen supplements work?

Many people swear by the numerous purported benefits of collagen supplements, but scientific evidence appears to be lacking, writes Sanet Oberholzer

02 April 2023 - 00:00
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Collagen supplements hold promises of youth at exorbitant prices. But do they work?
Collagen supplements hold promises of youth at exorbitant prices. But do they work?
Image: 123RF/yulisitsa

We’ve heard the promises: collagen will improve your skin’s elasticity and hydration, promote healthy hair and nails, prevent bone loss, boost muscle mass and relieve joint pain. It may even help reduce your chances of pesky ingrown toenails, assist in treating arthritis and reduce the risk of heart conditions. No wonder people are willing to pay hundreds of rand for a few hundred grams: it’s marketed as a wonder supplement. And a cash cow it is! According to Future Market Insights, the global demand for collagen supplements is set to reach $2.8bn (more than R50bn) by 2032. But what is it and does it really work?


Collagen is a protein that makes up about 80% of our skin, 60% of cartilage and 30 to 40% of protein in the body. It provides tissues with an elastic quality and is crucial for the formation of connective tissue, the structural component in skin, bone, muscles, cartilage, tendons, hair, nails, blood vessels, intestinal lining — even organs.  

As we age, natural collagen production drops and the well-organised network of such fibres in our bodies starts to fray, a process sped up by environmental factors such as sun exposure, smoking, excessive alcohol consumption and too little exercise and sleep.

More than 20 types of collagen have been identified in the human body, but three are usually found in collagen supplements: type I, found in skin, bones, ligaments and tendons, provides elasticity and strength; type II makes up cartilage; and type III is found in skin, blood vessels and organs with type I collagen.


“‘What are our thoughts on collagen?’ is the most common question I'm asked by clients,” says Philippa Bramwell-Jones, registered dietitian and founder of Joburg-based Intuitive Nutrition. “I’m in favour of supplementation, but there should be valid reasons behind it and it should be well sourced, bioavailable and measurable.”

Bramwell-Jones is convinced research shows collagen supplements can benefit the treatment of osteoarthritic pain and type II diabetes, as well as assist in wound healing, skin ageing, post-exercise muscle recovery, loss of muscle mass, tendinitis, rheumatoid arthritis and hypertension.

But there are ways that work and ways that don’t. “Collagen must be digested and absorbed through the gut lining to provide benefits; it can't be absorbed in its raw form,” she says.

It would be a medical breakthrough if the claims made by companies producing collagen were true. Cosmetic practitioners wouldn't have a place in society
Dr Rakesh Newaj

“It's broken down into small particles called peptides (shorter protein molecules or short chains of amino acids) through a process called hydrolysation. Some collagen supplements contain these hydrolysed collagen peptides and others don't. The hydrolysed version is far superior in its bioavailability.”

Once digested, collagen is broken down into amino acids which the body uses when it needs protein; they aren't always used in the production of collagen.

Forget about vegan supplements that claim to do the same job as non-vegan ones. “Plants provide the ingredients needed for the manufacture of collagen, but don't contain collagen itself,” she says.

“Humans are able to synthesise collagen and so are all other animals. Collagen supplements therefore come from two sources: animal-based (usually ovine, bovine or porcine) or marine-based (usually fish skin or scales, shellfish or jellyfish).

You can surmise that eating a healthy, balanced diet could replace the need for supplements by promoting natural collagen production.

According to an article by Harvard’s School of Public Health, last reviewed in 2021, “natural collagen production is supported through a healthy and balanced diet by eating enough protein foods, whole grains, fruits and vegetables, and reducing lifestyle risk factors”.

Bramwell-Jones says a good way of adding collagen to your diet, without breaking the bank, is by making bone broth.


I asked Dr Rakesh Newaj, a Johannesburg-based dermatologist specialising in diseases of the skin, hair and nails, what his opinion is of collagen supplements. He confirmed a nagging rationale: “It would be a medical breakthrough if the claims made by companies producing collagen were true. Cosmetic practitioners wouldn't have a place in society.

"Collagen supplements are useless to the skin. First, collagen is already broken by the acids in the stomach. Little, if any, is absorbed. Some companies claim that they tagged the ingested collagen with a radioactive material and detected the radioactive collagen in the dermis. This doesn't prove that the radioactive collagen was of any use in boosting elasticity and health,” Newaj says.

Collagen’s effectiveness in skin creams and serums is also dubious. As the Harvard article states: “Collagen is not naturally found on the skin’s surface, but in the deeper layers. The fibres are too large to permeate the skin’s outer layers and research hasn't supported that shorter chains of collagen, peptides, are more successful at this feat.”


What about claims that collagen supplements relieve joint pain or prevent disease? “We need more robust, scientific studies to confirm a beneficial effect in prevention and treatment of osteoarthritis and osteoporosis,” says Teréza Hough, CEO of the National Osteoporosis Foundation of South Africa.

Her claim is supported by world-renowned expert in the field Prof Jean-Yves Reginster of the University of Liège in Belgium and the president of the European Society for Clinical and Economic Aspects of Osteoporosis and Osteoarthritis (ESCEO).

“In osteoporosis, no robust scientific data supports the positive action of these compounds,” Reginster says. “There are some small studies, including one from my department, which can be considered as preliminary reports suggesting that in some cases, a mild benefit could be obtained.  

“At this stage, ESCEO doesn't recommend the use of collagen supplements for osteoarthritis andI don't see any reason why we should consider these chemical entities for the treatment of osteoporosis."


According to a 2019 article in The New York Times, “some studies show that taking collagen supplements for several months can improve skin elasticity as well as signs of ageing. Others have shown that consuming collagen can increase density in bones weakened with age and can improve joint, back and knee pain.”

The problem is, many of these studies were funded by companies that produce collagen supplements or written by authors who are tied to these industries.

The bottom line: initial data appears to be there but more evidence is needed — not least to rule out conflict of interest or biased studies. For now though, opinions are divided until more concrete science becomes available.

If you're willing to fork out the kind of money needed to sustain a monthly supply of collagen supplements in the long run, they haven’t been shown to cause any negative side effects. You could also reduce harmful external factors and consider a healthy, balanced diet an alternative to expensive supplements.

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