NEW
💅 Keratin
Cost per serving
$0.06
Cheap·−86%
other · 6 active deals
The best-value Keratin right now is about $0.06 per dose — across 6 tracked products the median is $0.137/dose, so shopping on cost-per-dose can cut your cost several-fold. Every Keratin deal here is ranked by cost per dose— what you actually pay per serving, not the sticker price — because forms and absorption differ, so the cheapest bottle isn’t always the cheapest dose.
Right now the best value across our full Keratin catalog is at $0.06 per serving.
Keratin is the structural protein of hair and nails; the supplement is a solubilized (hydrolyzed) keratin, usually sold under the branded form Cynatine HNS, marketed for hair and nail strength. Be clear-eyed about the evidence, because it is the thinnest of any beauty active we track: it rests on a single small trial (50 women, 90 days) that was funded by the ingredient's manufacturer (Roxlor Global) and co-authored by its general manager. That trial reported improvements in hair loss and nail hardness and concluded the supplement is "effective," but there is no independent replication, and because the product combines keratin with a vitamin and mineral stack, any benefit cannot be pinned on the keratin itself. — per the Cynatine HNS clinical trial (NIH PMC); not medical advice.
Sold as capsules stating milligrams of keratin per serving — the figure our cost-per-dose ranking uses. The studied amount was 500 mg/day (two 250 mg capsules), each also carrying zinc, biotin, niacin, copper, B6 and pantothenic acid; so a "keratin" product is typically a hair-skin-nails blend built around keratin, and its biotin content can interfere with some lab blood tests.
The evidence is the weakest of the beauty actives we track: a single small, manufacturer-funded trial (n=50, 90 days), funded by Roxlor Global — the maker of the ingredient — whose general manager was an author, reported improvements in hair loss and nail hardness and concluded the supplement "is an effective supplement for improving hair and nails." The product is keratin combined with a vitamin/mineral stack, so any effect cannot be attributed to keratin alone, and there is no independent replication. — per the Cynatine HNS clinical trial (NIH PMC); not medical advice.
In the single trial available, a 90-day study of solubilized keratin (Cynatine HNS) in 50 women, "there were no adverse events reported during the study." There is no long-term safety data and no established upper limit. Note that Cynatine HNS products also contain biotin, which can interfere with some lab blood tests (troponin, thyroid and hormone assays) — tell your doctor before testing. — not medical advice.
Source: NIH Office of Dietary Supplements — Keratin fact sheet
Every Keratin deal above is ranked by real cost per dose with no paid placement — see our and .
BulkSupplements.com Hydrolyzed Keratin Powder - Gluten Free at $0.06 — the lowest cost-per-dose keratin in our catalog. See the full ranking on the Best Keratin page.
We're tracking 6 active Keratin deals across Amazon US and partner retailers, ranked by community votes and cost-per-dose — not paid placement.
Across 6 tracked Keratin deals the median cost-per-dose is $0.137; the cheapest quartile comes in under $0.110 . Anything below the median is a solid deal for the same molecule.
Deals are submitted by the community and ranked by net votes (hot minus cold) plus cost-per-dose normalised across container sizes. We take no affiliate kickbacks for ordering; sponsored slots, when present, are clearly badged.
The evidence is the weakest of the beauty actives we track: a single small, manufacturer-funded trial (n=50, 90 days), funded by Roxlor Global — the maker of the ingredient — whose general manager was an author, reported improvements in hair loss and nail hardness and concluded the supplement "is an effective supplement for improving hair and nails." The product is keratin combined with a vitamin/mineral stack, so any effect cannot be attributed to keratin alone, and there is no independent replication. — per the Cynatine HNS clinical trial (NIH PMC); not medical advice.
We link primary sources and paraphrase their findings — never copy their text, tables, or images. Cost-per-dose figures are our own first-party catalog data.
Cost per serving
$0.06
Cheap·−86%Cost per serving
$0.16
Avg·−38%Cost per serving
$0.11
Cheap·−75%240 servings · ~240-day supply
Cost per serving
$0.18
Pricey60 servings · ~60-day supply
Cost per serving
$0.12
Avg·−69%120 servings · ~120-day supply
Cost per serving
$0.25
Pricey60 servings · ~60-day supply
Amazon.com · 💅 Keratin
CPS
Price
$31.97
Amazon.com · 💅 Keratin
CPS
Price
$37.71
Amazon.com · 💅 Keratin
CPS
Price
$25.99
Amazon.com · 💅 Keratin
CPS
Price
$11.09
Amazon.com · 💅 Keratin
CPS
Price
$13.99
Amazon.com · 💅 Keratin
CPS
Price
$14.95
In the single trial available, a 90-day study of solubilized keratin (Cynatine HNS) in 50 women, "there were no adverse events reported during the study." There is no long-term safety data and no established upper limit. Note that Cynatine HNS products also contain biotin, which can interfere with some lab blood tests (troponin, thyroid and hormone assays) — tell your doctor before testing. — not medical advice.
Dosage, upper-limit, deficiency, food-source and interaction facts are sourced from the NIH Office of Dietary Supplements Keratin fact sheet. General information, not medical advice.
500 servings · ~500-day supply
240 servings · ~240-day supply
