Collagen: What the Science Really Says.

Collagen is the most abundant structural protein in the human body — making up approximately 30% of our total protein content. It is literally the scaffolding that holds our skin, joints, bones, tendons, and blood vessels together. In longevity research, it has come to the forefront for a simple reason: from around the age of 25, the body's own collagen production declines by approximately 1–1.5% per year. From the age of 40, this decline accelerates noticeably.

That may sound abstract at first, but it manifests very concretely: reduced skin elasticity, joint stiffness, slower wound healing, decreased bone density. Longevity medicine is fundamentally the science of slowing these molecular decay processes — and collagen is a central target.

This is one of the most important questions, and unfortunately it is often not answered clearly in marketing materials. A regular collagen molecule is too large to be absorbed directly after oral intake — its molecular size is around 300,000 Daltons. Hydrolyzed collagen is enzymatically broken down into small dipeptides and tripeptides, typically below 3,000 Daltons, often below 1,000 Daltons.

These small peptides are intestinally absorbable. Crucially, after absorption they do not simply get used up — they act actively: they stimulate fibroblasts — the collagen-producing cells in the skin — through receptor signalling pathways such as ERK/MAPK and PI3K/Akt. This means they signal the body to produce more of its own collagen.

Absolutely necessary — I would go so far as to say: without Vitamin C, a collagen formula is incomplete. Vitamin C is an indispensable cofactor for two enzymes critical to collagen stability: prolyl-4-hydroxylase and lysyl hydroxylase. These enzymes hydroxylate proline and lysine in the pro-alpha chains — a process that is absolutely required for the formation of the stable triple-helix structure of collagen.

Without sufficient Vitamin C, structurally unstable collagen molecules are produced. Historically we know this as scurvy. In modern supplementation this extreme case is not the concern, but the principle is identical: less Vitamin C means less functional collagen. Additionally, Vitamin C acts as an antioxidant directly in the skin: it reduces UV-induced oxidative stress, inhibits melanin synthesis, and protects the dermal collagen matrix from degradation by free radicals.

Hyaluronic acid is a glycosaminoglycan — a complex sugar molecule — that occurs naturally in skin, joint cartilage, and synovial fluid. Its most remarkable property: it can bind up to 1,000 times its own weight in water. This makes it the most powerful natural moisture reservoir we know of.

In combination with collagen, it acts on two levels. First, it complements the structural support function of collagen in the skin matrix — collagen provides tensile strength, hyaluronic acid provides volume and turgor. Second, it lubricates joints: in synovial fluid, it significantly reduces friction between cartilage surfaces.

BioPerine® is a patented black pepper extract standardised to at least 95% piperine. And it is, in my view, one of the most underestimated elements in nutritional supplement formulas. Piperine inhibits certain metabolic enzymes in the intestinal mucosa and in the liver — specifically CYP3A4 and P-glycoprotein — which normally break down a significant proportion of ingested active compounds before they enter the bloodstream.

The result: the bioavailability of the other ingredients increases by 30–50% in clinical studies. If the collagen formula without BioPerine® has an absorption rate of 60%, BioPerine® can raise this to up to 90%. This is not a marginal effect — it is a fundamental difference in the actual concentration of active compounds reaching the tissue.

This is the question I always ask my patients when they purchase nutritional supplements: who developed it, and how was it tested? The market is unfortunately flooded with products that promise impressive ingredients but neither disclose dosages nor have been independently tested for purity and potency.

This is not marketing — it is the minimum I expect as a physician from a serious product. And honestly: many do not meet it.

In principle, the clinically relevant collagen decline begins at around age 25 — but for most people the tangible effects appear in the mid-to-late thirties. I see four main groups that benefit particularly:

Hydrolyzed collagen is considered very well tolerated and safe at recommended dosages. A few points to be aware of:

Collagen is not a medication with an immediate effect. Collagen works on biological timescales — on the timescale at which your skin renews itself, your cartilage cells regenerate, your fibroblasts are activated. That takes time.

Results are significantly better with consistent daily intake than with irregular use. Collagen is a daily investment — not an occasional supplement.

I am selective when it comes to recommendations. In my practice I only recommend products when I am convinced by the formulation, quality assurance, and scientific basis.

REVVY® Collagen convinces me on several levels: the dual Peptan® combination of bovine and marine peptides covers different collagen types. BioPerine® demonstrably increases efficacy. The accompanying nutrients — Vitamin C, hyaluronic acid, biotin — have not been added arbitrarily, but are physiologically well-chosen. And the quality assurance meets the standard I expect as a physician.

What additionally convinces me is the Swiss development. Regulatory standards in Switzerland and the EU are very high by global comparison. This gives me as a physician — and should give consumers — considerable confidence.