Edible Collagen: Why It Isn't Absorbed Directly into the Skin and How to Choose Correctly

An increasing number of people are looking for inner beauty supplements such as collagen or hyaluronic acid for skin elasticity and hydration. However, questions remain as to whether nutrients consumed orally are delivered directly to the skin to cause dramatic changes. Professor Oh Seung-won of the Department of Family Medicine at Seoul National University Hospital explained the absorption process of edible collagen, the limitations of its actual efficacy, and the matters that must be checked when choosing a product through a Seoul National University Hospital TV video.

The reason collagen intake does not go directly to the skin

While many expect that consuming collagen will deliver its components directly to the skin, our body's digestive system works differently. Collagen is a type of protein, and when consumed, it passes through the stomach and intestines to be broken down into amino acids or small peptide fragments. These broken-down nutrients move throughout the entire body, and our body prioritizes allocating nutrients to repair essential vessels, muscles, and organs for survival. In other words, because facial skin elasticity is low on the priority list for maintaining life, consumed nutrients are not allocated to the skin first.

However, according to recent research, there is a hypothesis that collagen is not completely broken down into only amino acids, but some is absorbed in the form of small peptides, which can signal skin cells to induce collagen synthesis. Therefore, while edible collagen and hyaluronic acid may provide some help to skin-related indicators, it is difficult to expect a magical effect that makes the skin young again as depicted in advertisements.

Low-molecular collagen and hyaluronic acid, what is the effective way to choose?

The explanation that 'low-molecular fish collagen' with a small molecular weight has a high absorption rate makes sense, but this does not directly translate to skin improvement effects. The difference in efficacy depending on whether it is fish-derived or animal-derived is also not overwhelming. There are also studies suggesting that hyaluronic acid can have a positive effect on hydration, but this may be a temporary supply of moisture and differs from fundamentally improving the skin barrier itself. If basic lifestyle habits such as sufficient sleep, water intake, and the use of moisturizers are not supported, there are limits to supplements alone.

Then, what should be checked when selecting supplements? Professor Oh Seung-won presented the following four criteria.

First, check for the 'Health Functional Food' label and specific functionality. It is important not to look only at the content of the ingredients, but to check whether the product has been recognized by the Ministry of Food and Drug Safety for functionalities such as 'may help in skin hydration.' Second, in the case of complex products, check for overlapping ingredients. If Vitamin C, biotin, or zinc are included, they may overlap with multivitamins already being taken, leading to excessive intake. Third, check for allergies and target groups requiring caution. Fish-derived products may be unsuitable for people with seafood allergies, and pregnant or breastfeeding women need to be careful before consumption. Lastly, if symptoms such as itching, discharge, inflammation, or rash appear on the skin, it is a priority to visit a medical institution for treatment rather than relying on supplements.

In conclusion, it must be kept in mind that the most important things in preventing skin aging and maintaining health are basic lifestyle habits such as using sunscreen, sufficient water intake, consuming vegetables and fruits, and sufficient sleep and moisturizing, rather than a single packet of expensive supplements.