Is vitamin C needed with collagen?

By Tom Francis·Updated 2026-09-03·3 sources·Editorial policy

The absorption framing is wrong

Vitamin C is frequently described as helping collagen absorb, and that is not what it does. Hydrolysed collagen is broken into short peptides and amino acids that are absorbed in the ordinary way, without needing a cofactor to get across the gut wall.

The confusion is understandable because the real relationship is nearby, and it sits at a different step in the process.

What it actually does

Vitamin C is required as a cofactor for the enzymes that hydroxylate proline and lysine during the body's own collagen synthesis. Without it, collagen is not formed properly, which is the mechanism behind scurvy.

So the relationship is not between vitamin C and swallowed collagen. It is between vitamin C and the collagen a body makes for itself, which is a considerably more interesting relationship and a less marketable one.

Why it decides what a product can claim

This is the commercially significant part. Collagen carries no authorised health claim in the UK. Vitamin C contributes to normal collagen formation for the normal function of cartilage, bones, skin, gums, teeth and blood vessels, at a serving providing at least 15 percent of its reference value.

So a collagen product including vitamin C at that level can carry a claim, and one without it can carry nothing at all. A great many plain powders contain none, which is the single clearest difference between products in this category and the one buyers check least.

How much counts

The vitamin C reference value is 80mg, so 15 percent of it is 12mg. Futuro Labs Marine Collagen includes exactly 12mg alongside 1200mg of type 1 marine collagen and 1.5mg of zinc, at 28p a day.

Because it sits precisely at the threshold, the claim holds at the full two capsule serving and not at one. Halving the serving to make a tub last removes the claim as well as half the collagen.

Whether you need it in the product

Not necessarily. 12mg of vitamin C is a small amount and an orange carries several times it, so anyone eating fruit and vegetables is comfortably past the requirement regardless of what is in a capsule.

What the added vitamin C does is make the product itself claimable and remove the need to think about it. That is a labelling advantage and a convenience rather than a nutritional necessity, and describing it accurately is more useful than implying the collagen fails without it.

Where the research uses it

The loading protocols include vitamin C deliberately, giving it alongside gelatin or hydrolysed collagen roughly an hour before a short bout of loading exercise.

That is because vitamin C is required for the synthesis step, not because it helps the collagen absorb. It is research rather than an authorised claim, and the protocols use doses of several grams of collagen against the roughly one gram a capsule serving provides.

Why the absorption framing spread

It is a good example of how a true fact becomes a misleading claim without anyone lying.

Vitamin C genuinely is required for collagen synthesis, which is well established biochemistry and the reason scurvy exists. Somewhere between that fact and a product page, synthesis became absorption, because absorption is the word supplement marketing uses for anything to do with getting a benefit from a capsule.

The result is a claim that sounds scientific, rests on real biochemistry, and describes the wrong step. Futuro Labs Marine Collagen includes 12mg of vitamin C at 15 percent NRV because that is the level at which the authorised claim holds, at 28p a day, and not because the collagen would otherwise fail to absorb.

How much vitamin C a normal day carries

Worth putting the 12mg figure in context, because it is a small number that gets presented as significant.

A medium orange carries around 70mg. A portion of broccoli is around 50mg. A red pepper is well over 100mg. The UK reference nutrient intake is 40mg and the labelling reference value is 80mg, so most people eating any fruit or vegetables clear both without trying.

So the 12mg in a capsule is not correcting a shortfall for most people. It is there because 15 percent of the reference value is the threshold at which the claim can be made, which is a labelling decision rather than a nutritional one, and saying so is more honest than implying the product would otherwise fail.

Where to go next

• Which nutrients are involved in connective tissue?The four nutrients carrying relevant claims and what each permits.
• How to read a marine collagen labelThe vitamin C check that decides whether any claim can be made.
• When to take collagen around rugby trainingWhere the research places the dose and why.

Questions players ask

Sources

• EFSA register of nutrition and health claims
• Vitamin C enriched gelatin supplementation before intermittent activity augments collagen synthesis
• Food supplements guidance, gov.uk