Collagen is perhaps the most common protein in the animal world. It is only responsible for about four percent of our body weight. If we joined together all the collagen fibers in our bodies, it would reach a length of about one hundred trillion (1014) meters—a distance so great that if we attempted to cross it at the speed of light, the endeavor would take us roughly four days.
In recent years, dietary supplements containing collagen have been growing in popularity. Collagen is a really impressive protein, but do we really need it as a supplement? To answer this, we must understand what collagen does in our bodies and how it is produced.
It is no coincidence that collagen is so common in our body, as it is largely responsible for the integrity of our bodies and the strength of our tissues.
That’s because collagen is the main building block of the extracellular matrix – the collection of fibers, enzymes and polysaccharides responsible for holding all of your body’s cells together and providing tissues with structural support, a substrate for growth and more.
Collagen’s role in this matrix is somewhat similar to that of steel rods in concrete in modern buildings. In fact, collagen fibers can be 5-10 times stronger than steel, and can withstand stretching up to half their length without tearing.
Similar to many other proteins, collagen fibers are made of smaller protein chains. These chains coil together in a triple helix of three collagen units, and the two spirals are twisted together into very strong braids.
Although the basic units are 330 nanometers (billionths of a meter) long, single collagen fibers can be several millimeters long—a huge size for a single molecule.
Collagen is found in all tissues of the body, but its concentration is particularly high in tissues that require significant structural strength, such as skin, bones, teeth, tendons, muscles, and blood vessels.
Because of its role in these tissues, it is no wonder that collagen is intimately involved in damage repair processes. For example, when we have a skin wound, the collagen fibers will be cut and realigned to repair the injured tissue.
However, the repair process is not without accidents, and excess collagen build-up in the skin may leave a scar.
In internal organs, the buildup of collagen may lead to a condition called fibrosis, in which collagen fibers, similar to a scar, displace healthy tissue, impairing the function of the organ. Fibrosis can affect many body systems, especially organs such as the lungs, kidneys, heart, and liver.
In recent years, dietary supplements containing collagen have grown in popularity. Similar to all other proteins in our bodies, collagen is produced in our tissues on demand, when they are being built or replenished, and therefore we do not need an external excess of collagen.
Even if we had such a need, the amount of protein in food supplements is very low, if not completely negligible, and will not affect the functioning of the body in the least.
On the upside, and for the same reason, this supplement cannot harm us – fibrosis develops due to lack of collagen removal and breakdown, and under normal circumstances excess collagen is broken down into its building blocks.
Collagen is used in cosmetics in creams, but there is a different role; It is not meant to be absorbed by the skin, but rather acts as a water absorbent in order to retain moisture and thus enrich the cream. Collagen is not unique in this role, and is often replaced by derivatives of vitamins, lactic acid, various alcohols, and other molecules.
But the really important point is that the collagen in these supplements will simply not reach its destination, because it will be broken down before long.
In the late 1970s, it was found that collagen, similar to other proteins, is hydrolyzed in the digestive tract into its constituent amino acids, and therefore its consumption by ingestion is similar to the consumption of any other protein in our food.
Moreover, collagen itself does not contain an exceptional amount of essential amino acids, so even if we lack the building blocks of protein, there are more readily available sources in the food we eat.
Furthermore, most collagen supplements do not contain collagen in it’s whole form at all. As mentioned earlier, collagen is a very large protein, and as a result it cannot cross the intestinal walls where it is supposed to be absorbed (it would be very bad if it did).
To enable its absorption, manufacturers break down collagen into its building blocks — short protein fragments called peptides or even individual amino acids. Although these fragments can be absorbed by the body, they are not collagen, in the same way that shards of glass do not function like the plate they were once part of.
This is why there is no advantage to consuming collagen-derived amino acids instead of amino acids and peptides derived from any protein-containing foods.
However, the supply of these supplements is constantly growing, and it’s no wonder – the global beauty supplement market is expected to reach seven billion dollars by 2024, and manufacturers have a strong incentive to develop new products.
In an independent study of 176 dietary supplements, physicians from the us found that most of these products included outdated dietary recommendations and made medical claims that were not supported by independent research studies.
In their report, the researchers emphasized that the companies were able to make such claims because of the relatively moderate control of dietary supplements, in contrast to medical treatments that must meet more stringent requirements.
The researchers also note that while these are only dietary supplements, they are not without risk, and still need to be tested for potential effects on pregnant women, drug interactions, and more.
A review by harvard medical school sheds some light on the status of collagen supplements and illustrates the importance of independent scientific studies. The review revealed that most of the studies published to date on the activity of collagen supplements have been funded by the supplement manufacturers themselves.
One of the most important factors for the credibility of scientific research is its independence, that is, the authors of the study are not concerned with obtaining a specific result.
When a study on a dietary supplement is funded by the company producing it, particularly when the company is actively involved in that research, there is concern that the study will be fundamentally biased, because it is clear that the manufacturers have a huge stake in the success of their products.
In fact, many studies’ author lists included employees of the company itself, and in one study credit was given to the CEO of the company. However, studies on collagen supplements have failed to demonstrate that there is a difference between consuming collagen and a balanced consumption of proteins as part of a balanced diet.
Therefore, our body is a well-oiled metabolic machine. Thus, it is able to convert proteins absorbed from food into their building blocks – amino acids – and produce whole body proteins.
Collagen is only found in foods of animal origin, but despite this there is no evidence that a vegan diet has any kind of effect on the production of proteins and collagen by the body, as long as it contains the right proportions of essential amino acids.
The importance of scientific research to understanding the world is enormous. However, science itself is also a product of human activity, and therefore it is not without prejudices. Therefore, it is crucial that scientific research be conducted in a transparent, honest and independent manner.
In a field with such high economic incentives, the apparent absence of independent studies is particularly frustrating and does not bode well for the necessity of these nutritional supplements.