Collagen supplements are big business. And is it any wonder when they are touted as the solution for ever youthful and glowing skin. With plenty of A-list celebrities singing its praises, it is no wonder collagen is having its moment in the spotlight. And a look at Google Trends shows search interest in collagen supplements really took off at the start of 2019 and it is showing no signs of slowing down.
Reading the shopping list of health claims made about collagen—from turning back the clock on your skin, treating joint pain and even ‘healing your gut’—you should rightly raise your sceptical flag. Yet when you look at the scientific evidence, there could just be some validity to some of these claims.
What is collagen?
Collagen’s key role is as a major structural protein in numerous tissues of the body including tendons, ligaments, cartilage, blood vessels and skin. It is so abundant in the body, that it makes up almost 30 percent of our total protein mass. The structure of collagen is defined by a triple helix arrangement which forms an incredibly strong structure. Think of collagen as like a rope with many fibres intertwined to make it super strong. No wonder then its key role is in forming a scaffold for the structure and strength of tissues such as skin and bones.
Collagen is not one molecule, but at least 28 distinct types. But it is Types I, II and III collagens that are the most abundant in the body. You’ll find type I collagen in the connective tissue of tendons, ligaments, corneas, bones and skin. Type III collagen is usually found along with type I collagen in the skin and blood vessels. While type II collagen is primarily found within cartilage.
When it comes to commercial oral collagen supplements, it is hydrolysed collagen that dominates the market. ‘Hydrolysed’ simply means the breaking down of a molecule with water. Hydrolysed proteins are smaller in length compared to undenatured whole proteins, so they are usually absorbed faster and more efficiently.
The collagen that is used in supplements can be derived from numerous sources including from cattle, pigs, chicken and marine sources. It is a nice use of what would mostly be a waste product in the processing of these animals and fish for human consumption. Marine collagen is a common source for use in supplements and is similar in terms of biocompatibility and amino acid content to the collagen from pigs or cattle.
If you have been paying attention, you would have noticed that all the sources of collagen I’ve mentioned come from animals or fish. Yet you may have come across vegan collagen sold as a supplement. And all I can say is that I’m calling vegan collagen a scam.
Firstly, plants don’t make collagen. End. Of. Story. In a lab, collagen can now be made using genetically modified yeast and bacteria, but this form of collagen is not widely available. And I don’t know how well the terms ‘GMO’ and ‘lab-grown’ may gel with a vegan philosophy.
If you see collagen being promoted as vegan it is usually a sleight of hand by focussing instead on a mixture of amino acids and peptides that could be similar to what you find in hydrolysed collagen. Research to support any health claims with this sort of mixture? Zero.
Collagen metabolism 101
But why even bother with collagen? Surely all protein just becomes an amino acid soup in our body after digestion? Hydrolysed collagen reaches the small intestine where it is absorbed into the bloodstream, both in the form of small collagen peptides and free amino acids. These collagen peptides and free amino acids are then distributed in the human body, in particular to the skin, where it has been shown they can remain in place for up to 2 weeks.
Those collagen peptides can also interact with skin fibroblast cells to mimic peptides naturally produced from the catabolic breakdown of the body’s own collagen. The result is stimulation of the fibroblasts to increase their collagen metabolism and a higher production of dermal collagen.
So, there is some functional specificity here in how the body treats collagen in our diet for how it contributes to connective tissue building rather than just entering into the general protein and amino acid pool. This is a critical point as it gives a potential mechanism to explain why clinical studies seem to point to a benefit of taking collagen. More on that in a minute, but first: a detour into bone broth.
Is bone broth a good source of collagen?
We can thank the Paleo fad for launching an explosion in interest in bone broth. The extensive list of health claims made about this miracle substance is astounding. Almost as astounding as the lack of any solid evidence to support the claims.
Bone broth is made by simmering bone and connective tissue of various animals for extended periods to extract collagen (in the form of gelatin which is just the name for cooked collagen) as well as additional amino acids, minerals, and bone marrow.
Unlike gelatin though, hydrolysed collagen is more suitable for taking as a supplement because it dissolves in water and is well absorbed. And the other big issue with using bone broth as a source of collagen is that there no way of knowing how much collagen is in your homemade or commercial broth. And at least one study has found a lower content of the key amino acids glycine, proline and hydroxyproline in bone broth compared to a collagen supplement. That’s why the commercial hydrolysed collagen supplements are so popular because of the known dose. And once you know the dose you are in the ballpark for potential health benefits for your skin and even more.
Collagen and your skin
The sad fact of ageing is that the amount of collagen in our body and skin declines. After the age of 18, we lose about 1 percent of it each year. And by the time we are 80, we may have just a quarter of the collagen in our skin compared to when we were young adults.
Less collagen means weak, wrinkly and aged skin. Enter collagen supplements. And this is where we now have what I consider a small, but growing body of clinical trials showing promising results for collagen supplements improving skin health.
Take one study for instance from 2014. It was a randomised placebo-controlled trial in 69 women between the ages of 35 and 55 years who were randomly allocated to one of three groups. The women took either 2.5 grams or 5 grams of hydrolysed collagen each day or were given a placebo powder. And they did this for 8 weeks. There was a significant improvement in skin elasticity in the collagen groups at the end of the study. And there was also an indication that skin moisture was also improved.
The above study doesn’t stand on its own. I can now count over a dozen human randomised placebo-controlled clinical trials published so far looking at collagen supplements on markers of skin health and ageing. In fact, a recent systematic review brought together most of the research on the use of oral collagen supplements on skin health. Eleven studies were included involving over 800 people and with doses of collagen hydrolysate ranging from 2.5 to 10 grams per day for up to 6 months.
And the conclusion? Positive and promising results for wound healing and skin ageing which included increased skin elasticity, hydration and dermal collagen density. And with every study showing some type of positive outcome. All with no reported adverse events.
Some of the studies used additional ingredients in the ‘secret sauce’ of collagen supplements such as vitamins C and E, biotin and zinc. But taking the research as a whole, it does suggest that the consumption of hydrolysed collagen may be effective at improving markers of skin ageing. There isn’t yet enough detail to know if there are differences in what type of collagen is best as far as the source of it or if it should be Type I, II, or III or a mixture.
It doesn’t stop at a benefit for skin health though. There is now a growing research field on the effect of collagen supplements on osteoarthritis. Osteoarthritis is a degenerative disease of joint cartilage resulting in pain and swelling and making it hard to move around for activities of daily living.
Multiple clinical trials find that oral hydrolysed collagen may be an effective supplement in managing the painful symptoms of osteoarthritis. And there has even been a meta-analysis published in this area in 2018 which showed that hydrolysed collagen is effective at improving osteoarthritis symptoms. The analysis could include data from five randomised placebo-controlled trials where collagen was taken by people with osteoarthritis. Typical doses ranged from 2 to 10 grams per day. Common benefits reported by those who took the hydrolysed collagen supplement was a decrease in pain, stiffness, and functional limitations.
Other benefits of collagen
Hydrolysed collagen may also be beneficial in athletes with joint pain and discomfort caused by their sport. In one study, 73 athletes who consumed 10 grams of collagen daily for 24 weeks experienced a significant decrease in joint pain while walking and at rest, compared with a group that did not take it. In another study, athletes with functional knee pain who took 5 grams of collagen daily for 12 weeks had a significant reduction in activity-related joint pain and were better able to engage in physical activity than those who did not take it.
And it’s not all about skin and joints. There is some really interesting preliminary work showing that hydrolysed collagen may be effective at improving insulin sensitivity, glucose and lipid metabolism, and reducing hypertension in people with type 2 diabetes.
Gut health fail
I want to make a special mention of gut health because it comes up a lot in those promoting collagen – especially in the more Insta influencer world. There is zero evidence in humans to support collagen doing anything to ‘plug those holes’ in your ‘leaky gut’. That doesn’t mean that it will do nothing, only that the claims made in this space are based on some very courageous leaps of logic from the amino acid content of collagen.
What it all means
For hydrolysed collagen, it reads like a shopping list of health benefits that sound too good to be true. But for those who are regular readers of this blog, you would know that I have a high evidence threshold for making claims, and at least with collagen, there definitely appears to be something to the story. That makes oral hydrolysed collagen supplements potentially beneficial in offsetting some of the physiological declines associated with ageing.