Collagen and ageing: the real effects on skin, joints and weight

Collagen is the most abundant structural protein in the human body. It is found in the skin, tendons, ligaments, bones, cartilage, and many connective tissues. Its role is essential: it contributes to the strength, flexibility, and cohesion of tissues [1].

The natural production of collagen begins to slow down from adulthood. Over the years, this decline becomes more pronounced. From the age of 25, natural collagen production decreases by approximately 1.5% per year, and by the age of 35, we have already lost nearly 20% of our reserves [2].

Certain everyday factors can also accelerate its breakdown, such as excessive sun exposure, smoking, alcohol, lack of sleep, pollution, or an unbalanced diet.

This gradual decline is not only visible on the face. It also affects joint comfort, tissue tone, and more broadly, the way the body changes over time.

Skin that is less firm, less supple and more easily lined

When collagen decreases, the skin gradually loses some of its natural support. It becomes less firm, less elastic and often less well hydrated. Fine lines and wrinkles appear more easily, and the skin texture can seem less plump.

This is one of the reasons why collagen is so widely studied in the field of skin ageing. It is not a miracle ingredient capable of turning back the clock, but a valuable support for helping skin through its natural changes.

What the studies on supplementation show

The most robust studies on collagen peptide supplementation show benefits for skin hydration, elasticity and firmness. Effects have been observed with daily intakes of 2.5 to 3 g per day, generally over a period of 8 to 12 weeks [3][4].

In practice, this means that taking collagen regularly may help improve the appearance of the skin, provided it is taken over the long term. Results are gradual: skin often appears more supple, better hydrated and less lined.

Which collagen is best for skin?

For skin, hydrolysed marine collagen is often the preferred choice. It is primarily rich in type I collagen, which is abundantly present in the dermis. In hydrolysed form, it is broken down into smaller peptides, which supports absorption.

This is also one of the reasons why marine collagen is so often used in food supplements targeting skin radiance, firmness and suppleness.

Ageing is not limited to visible signs on the skin. It also affects the supporting tissues, in particular cartilage, ligaments and tendons. Over time, joints can become stiffer, less comfortable and more sensitive to physical exertion.

Why joints become more sensitive

Cartilage acts as a natural shock absorber between the joints. Its structure also changes with age. As tissues lose quality, mobility can become less fluid and certain discomforts may appear more readily, particularly in the knees, hips or wrists.

Collagen is indeed a component of these tissues, which is why it attracts so much interest in the field of joint comfort.

What to expect from collagen

Collagen supplementation may help to improve joint comfort and reduce certain feelings of discomfort, particularly in people who are beginning to experience age- or wear-related discomfort. The effects observed depend on the form used, the dose and the consistency of intake.

For joints, studies often use higher doses than for the skin. 

A dose of around 10 g per day of hydrolysed collagen is frequently used. Results have shown, for example, that in healthy subjects with knee osteoarthritis, this could potentially reduce pain, improve quality of life and reduce functional impairment [5].

Here too, it is important to remain realistic: collagen is not a medical treatment, but a useful support for preserving joint comfort over time.

The link between collagen and weight gain is often misunderstood. Collagen is not a "slimming" ingredient as such. It does not melt fat on its own, and it should not be presented as a supplement for weight loss.

However, it may be of interest as part of a broader approach to the body's ageing process.

The body changes with age, not just on the scales

Over time, body shape often changes for several reasons: a gradual decline in muscle mass, hormonal changes, reduced physical activity, loss of tissue tone and a relative increase in body fat. The number on the scales therefore does not tell the whole story.

In this context, collagen may be of interest not for "weight loss", but to support tissue quality and body composition in certain situations.

What we can say concretely

Some studies suggest that collagen peptide supplementation, when combined with resistance training, may support a better change in body composition, with greater maintenance of lean mass and a more marked reduction in body fat compared to exercise alone.

For example, one study with a 15 g supplementation showed that it significantly helped improve the symptoms of sarcopenia compared to a placebo, through an increase in lean muscle mass and an improvement in muscle function [6].

In mice fed a high-fat diet, marine collagen helped limit weight gain and the increase in body fat. It also showed interesting effects on certain markers related to metabolism and inflammation. However, these are animal study results, not yet proven in humans [7].

The most accurate way to put it is therefore this: collagen does not cause weight loss, but it can support the changes associated with ageing by helping to maintain tissues, lean mass in certain contexts, and skin quality.

Tous les collagènes ne se valent pas. Pour faire un choix pertinent, il faut tenir compte de plusieurs critères : la forme, l’origine, la dose et la qualité de fabrication.

Le collagène hydrolysé

Le collagène hydrolysé, aussi appelé peptides de collagène, est la forme la plus utilisée dans les compléments alimentaires. Il s’agit d’un collagène découpé en fragments plus petits, mieux assimilés par l’organisme.

Un faible poids moléculaire est généralement recherché pour favoriser l’absorption.

Le collagène marin

Le collagène marin est particulièrement intéressant pour la peau. Il est souvent bien toléré, soluble et riche en collagène de type I. C’est aussi la forme la plus utilisée dans les produits orientés beauté et vieillissement cutané.

La bonne dose

Pour la peau, les bénéfices sont généralement observés à partir de 2,5 à 5 g par jour. Pour les articulations, des doses plus élevées sont souvent utilisées dans les études sur le collagène hydrolysé.

Au-delà de la dose, la régularité reste essentielle. Le collagène agit dans le temps. Une prise ponctuelle ne permet pas d’attendre les mêmes effets qu’une supplémentation suivie pendant plusieurs semaines.

Le collagène Jolly Mama

Chez Jolly Mama, nous utilisons un collagène de faible poids moléculaire (2000 Da) ce qui garantit une absorption optimale par le corps. Notre collagène est principalement de type 1. Ce collagène marin est extrait de poissons issus de la pêche durable dont on extrait les peptides de collagène. Il est garanti FRIEND OF THE SEA®. 

Une dose de notre complément de collagène goût pêche apporte 3g de collagène, soutenu par les études scientifiques. Nos produits sont également riches en vitamine C d'acérola naturelle. Existent aussi au goût cacao, café (sans caféine) et neutre. 

Et pour encore plus de gourmandise, notre snack Banana glow aux pépites de chocolat et banane contient lui aussi 3g de notre collagène.  

Supplementation can be helpful, but it does not replace the basics. To produce its own collagen, the body needs several key nutrients, including protein, vitamin C and zinc.

A few simple habits can also help to preserve existing collagen:

• protect your skin from the sun;
• avoid tobacco;
• limit excess alcohol;
• ensure adequate protein intake;
• get enough sleep;
• engage in regular physical activity.

Collagen therefore fits into a holistic approach to healthy ageing, rather than a single-solution mindset.

Collagen plays a far wider role than is often imagined. With age, its decline can manifest as less firm skin, less comfortable joints and changes in body shape linked to tissue quality and body composition.

Collagen supplementation, particularly in the form of hydrolysed marine collagen peptides, can offer useful support in accompanying these changes. The best-documented effects relate to skin and joint comfort. Regarding weight, a nuanced view is needed: collagen does not cause weight loss, but it can form part of a broader strategy to support the ageing body.