the nail study is the tidiest one in the whole category

Nails are boring. Nobody starts drinking collagen for their nails. But they were the first thing I noticed, they were the first thing a friend noticed without me saying anything, and they are the reason I kept going long enough to care about everything else.

the study

Hexsel and colleagues, 2017, published in the Journal of Cosmetic Dermatology. Twenty five participants with brittle nail syndrome took 2.5 grams of specific bioactive collagen peptides daily for 24 weeks, then went four weeks without.

Nail growth rate rose by 12 percent. The frequency of broken nails fell by 42 percent. Sixty four percent of participants showed clinical improvement in brittle nails, and 88 percent showed improvement four weeks after they stopped.

Twenty five people is not a huge trial and I will say so plainly. But the measurements are objective, they were taken over six months, and the effect sizes are not subtle.

why nails are such a useful signal

This is the part I find genuinely clever about using nails as your personal test.

Nails grow at roughly three millimetres a month from the matrix under the cuticle. That growth is a recording. Whatever your body had available when a section was formed is locked into that section permanently, and then it slowly walks out to the end of your finger where you can see it.

You cannot talk yourself into a nail. Skin is easy to imagine improvements in, because lighting and sleep and mood all interfere. A nail either broke this month or it did not.

So if you want an honest read on whether a collagen habit is doing anything for you, nails are the cheapest instrument you own.

the dose thing again

Two and a half grams a day, every day, for twelve weeks before the effect was clear. Not a pinch. Not four days out of seven.

Nail keratin is protein, and building it needs amino acids, particularly the sulphur containing ones plus a steady supply of the glycine and proline that collagen delivers in unusual abundance. If the supply is intermittent, the recording shows it. You can sometimes see the gaps as ridges.

what to actually do

Take a photo of your hands today. Not an artful one, just a flat photo in daylight. In twelve weeks take another one in the same light.

Then keep the habit steady in between, which is the entire difficulty. Twenty grams of collagen protein in a can you finish because you like it beats 20 grams in a tub you open twice.

The nails will tell you the truth before anything else does. That is why I trust them.

the research i leaned on

• Hexsel D, Zague V, Schunck M, et al. Oral supplementation with specific bioactive collagen peptides improves nail growth and reduces symptoms of brittle nails. Journal of Cosmetic Dermatology. 2017;16(4):520-526.
• de Miranda RB, Weimer P, Rossi RC. Effects of hydrolyzed collagen supplementation on skin aging: a systematic review and meta-analysis. International Journal of Dermatology. 2021;60(12):1449-1461.

LÉS is a beverage, not medicine, and nothing here is medical advice.