Does collagen help hair and nails?

The asymmetric pair: the one open-label nail study, the zero hair trials, and why neither appendage is built from what collagen supplies

Does collagen help hair and nails is a question that arrives as a pair because the shelf never sells the two apart, the words hair, skin and nails running together on every beauty collagen label as if they were one tissue with one evidence base, and the honest page splits them, because the two appendages have asymmetric evidence and a reader who hears the pair answered together hears the stronger side stretched across both. The nail side has one study, and the honest page describes it precisely because the shelf describes it loosely. Around twenty-five people with brittle nails, nails that split, peeled and broke, were given 2.5g of specific collagen peptides a day for twenty-four weeks, and at the end their nails were growing faster than at the start, by a millimetre or so a month, and were breaking less often, with most participants reporting improvement. That is the finding, and these are its limits: there was no placebo group, so nobody took a matching powder of nothing for twenty-four weeks for comparison; there was no blinding, so everyone knew they were taking collagen for their nails; the funding came from the peptide's manufacturer; and the condition studied, brittle nails, improves on its own with the seasons, with the hand care and reduced wet-dry cycling that joining a nail study prompts, and with the attention that measurement brings, so that nothing in the design could separate the collagen's contribution from all of that, which is why it is called an open-label study rather than a trial and why the nail clock on the collagen and nails timing page treats its result as a possibility to be checked with a cuticle mark rather than a finding to be bought on. It is also, and this is the asymmetry, one more study than hair has. No randomised controlled trial has given collagen alone, as powder, capsule, liquid or gummy, to anyone and measured hair growth, hair density, shaft thickness or shedding against a placebo, not once, in any population, which is a remarkable gap for the appendage that sells the most collagen; the trials quoted on hair-marketed collagen products gave proprietary complexes built around a marine protein extract with vitamin C, zinc, biotin, horsetail silica and other nutrients, and reported improved hair density and reduced shedding over three to six months in women with thinning hair, results that belong to a complex several of whose passengers hold hair claims in their own right and from which the collagen cannot be separated, with the hair cycle that makes any hair claim take six months to test on the collagen and hair timing page. The reason the evidence is thin on both sides is the same, and it is the protein. Hair and nails are made of keratin, a family of proteins quite different from collagen in sequence and structure, and keratin is built heavily from cysteine, the sulphur-containing amino acid whose disulphide bonds cross-link the keratin chains and give hair its strength and curl and a nail its hardness; collagen almost entirely lacks cysteine, being a third glycine and a quarter proline and hydroxyproline, so that the amino acid profile a collagen supplement delivers is nearly the inverse of what a hair follicle or a nail matrix assembles, and both draw their amino acids from the body's general pool, which any complete protein fills and which a reader eating enough protein of any kind is not short of.

The lawful sentences and who holds them, how to read a hair-and-nails label, the real drivers to check first, and the worked example

The register settles the pair from the regulatory side, and it settles it the same way for both. The authorised health claims for hair and nails belong to a short list of nutrients: biotin, zinc and selenium each contribute to the maintenance of normal hair, biotin, zinc and selenium each contribute to the maintenance of normal nails, and copper contributes to normal hair pigmentation, with the claims permitted on a product that supplies at least fifteen percent of the nutrient's reference value per daily dose; no other nutrient and no protein of any kind, collagen included, holds a hair or nail sentence, and a label that says collagen supports hair and nails has stepped outside the register. That is why a hair-and-nails collagen product almost always contains biotin, zinc or selenium beside the collagen: the passengers make the hair and nail claims lawful and the collagen rides along under them, so that a reader who wants to know what a product may honestly be said to do for their hair and nails reads the passenger list and ignores the collagen line, asking whether biotin, zinc or selenium is present at the fifteen percent threshold and whether they are plausibly short of any of them, which on a varied diet is rare for biotin and selenium and uncommon for zinc; the format question for hair, equal at zero in capsules and powder alike, is on the capsules versus powder for hair page. The real drivers of thinning hair and brittle nails are examined before any supplement, because they account for most cases and none of them is a collagen question. For hair: iron stores, which a ferritin test measures and which are low in many women with thinning hair; thyroid function; a shed three months after an illness, a birth, a crash diet or a shock, which resolves on its own over a hair cycle; and the hormonal pattern loss of a widening parting or a receding hairline, which a dermatologist treats and no nutrient addresses. For nails: wet-dry cycling and detergents, which split the nail plate's layers and which gloves and a cuticle oil address; age; iron again; and, rarely, a nail disease that a dermatologist recognises. A reader with brittle nails who wants to test the one open-label study's possibility marks one nail at the cuticle and measures the distance travelled a month later, before and six months into a 2.5g dose, and a reader with thinning hair counts the plughole for a set week before and after six months of anything, and both check the real drivers first. The worked example illustrates the passenger logic in its own label, stated on its true terms: two capsules, 1200mg hydrolysed type 1 marine collagen with 12mg vitamin C at 15% of its reference value plus zinc, 120 for £16.99 at 28p a day, lab tested and UK made, in which the zinc holds the maintenance of normal hair and normal nails sentences if it reaches its fifteen percent threshold, the vitamin C holds collagen formation for skin, and the 1200mg of collagen holds no hair or nail claim and sits below the 2.5g of the one nail study, so that a reader buying it for hair and nails is buying the zinc and should know it. Does collagen help hair and nails: nails, on one open-label study without a placebo, possibly; hair, on no trial of collagen alone, not that anyone has shown; and the sentences a label may print about either belong to biotin, zinc, selenium and copper.

What to check on the label