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.

Not all collagens are equal. To make an informed choice, several criteria need to be considered: the form, the origin, the dose and the quality of manufacture.

Hydrolysed collagen

Hydrolysed collagen, also known as collagen peptides, is the most widely used form in food supplements. It is collagen broken down into smaller fragments, which are more readily absorbed by the body.

A low molecular weight is generally sought to support absorption.

Marine collagen

Marine collagen is particularly beneficial for the skin. It is often well tolerated, soluble and rich in type I collagen. It is also the most widely used form in beauty and skin ageing products.

The right dose

For the skin, benefits are generally observed from 2.5 to 5 g per day. For joints, higher doses are often used in studies on hydrolysed collagen.

Beyond the dose, consistency is key. Collagen works over time. A one-off intake cannot deliver the same results as supplementation taken regularly over several weeks.

Jolly Mama collagen

At Jolly Mama, we use a low molecular weight collagen (2000 Da), which ensures optimal absorption by the body. Our collagen is primarily type I. This marine collagen is extracted from fish sourced through sustainable fishing, from which collagen peptides are derived. It is certified FRIEND OF THE SEA®. 

One serving of our collagen supplement peach flavour provides 3 g of collagen, supported by scientific studies. Our products are also rich in acerola vitamin C natural. Also available in cacao, coffee (caffeine-free) and unflavoured. 

And for an extra indulgent treat, our Banana glow snack with chocolate chips and banana also contains 3 g of our collagen.  

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.