Everything DoseRank tracks on the keratin skin care shelf — Huperzine A. The category itself is never ranked: 77 products get scored the moment you say what you want them to do.
How to read the scores
This legend covers the scores on this page — for data sources, scoring weights, and limits, read the full methodology →
Answer a few questions about your goals, habits, stack, and budget. Then, DoseRank will find the products that best match your needs based on your answers. It's free and only takes 60 seconds! No account is required.
A saved, shareable breakdown: your matched products, dose math, interaction flags to discuss with a clinician, and a price-tracked stack you can revisit.
Questions
Each product gets a composite score blending clinical strength, evidence, dose fit, trust and value — computed for the goal you picked, across this category's products. The #1 on the DoseRank tab has the highest composite; the other tabs re-rank the same products by Value, Trust, or Popularity. Placement is never paid.
Start with a goal, not a brand
Browsing keratin skin care supplements without a goal makes no sense — different products do different jobs, and “best” flips depending on which job you're hiring for. These are the 45 health outcomes that matter for this category. Pick yours, and the full evidence-ranked shelf loads for that goal alone.
Activities of daily livingCapacity to complete routine self-care activities independently.2 rankedStrong
Immune toleranceBalanced immune regulation without excessive reactivity.2 rankedLimited
Strength performanceMaximum or functional force production.4 rankedStrong
Reaction timeSpeed of physical or cognitive response to a stimulus.7 rankedStrong
Perceived exertionSubjective difficulty of physical effort.3 rankedStrong
Range of motionExtent of achievable joint movement.2 rankedModerate-strong
Hair growth or densityIncrease or preservation of scalp or body hair.7 rankedModerate-strong
Wrinkle severityDegree of visible skin wrinkling.7 rankedModerate-strong
Serum creatinineBlood marker commonly used to estimate kidney function.3 rankedStrong
Biotin statusBiochemical sufficiency of biotin.13 rankedStrong
Nail brittlenessFragility or easy breakage of nails.17 rankedLimitedSperm countNumber of sperm in semen.2 rankedLimited
Joint functionAbility of joints to move and support normal activity.15 rankedStrong
Nail strengthResistance of nails to splitting or breaking.13 rankedLimited
MemoryAbility to encode, store, and retrieve information.21 rankedStrongNothing is ranked yet — the shelf stays locked until you pick a goal.
No goal, no ranking.
A “best keratin skin care supplement” list without a goal would be marketing, not evidence. Pick what you want to improve and DoseRank scores all 77 products against that goal's trials.