What dose of Biotin & Keratin is effective for Nail strength?

Dose-range data is not available for this formula yet. DoseRank scores this product's dose fit at 77 out of 100.

How much does the best Nail strength supplement cost?

Life Extension, Hair, Skin & Nails, Collagen Plus Formula, 120 Tablets works out at $0.74 per serving. $0.74 per serving — high price tier for this outcome. The cheapest ranked pick here is $0.06 per serving.

Does DoseRank get paid to rank a product first?

No. Retailer links may be affiliate links, but rankings and placement are never paid. Every product is scored by the same public model, and the ranking is recomputed from the underlying product data rather than edited by hand.

The short answer · Nail strength

Take biotin & keratin for nail strength. This is the one to buy.

Life Extension, Hair, Skin & Nails, Collagen Plus Formula, 120 Tablets

4.7· 6,824 ratings· $0.74/serving

DoseRank score87

Biotin 2500 mcg — inside the studied 2500-5000 mcg window

Of 2,219 products scored for Nail strength, Life Extension, Hair, Skin & Nails, Collagen Plus Formula, 120 Tablets ranks #1 with a DoseRank score of 87. Evidence is still thin for Biotin and Keratin.

View on iHerb 60-sec quiz instead

Cheaper alternative$0.06 per serving21st Century, Biotin, 360 Tablets

Retailer links may be affiliate links. Rankings and placement are never paid.

The form“Why Biotin & Keratin?”

Evidence is still thin for Biotin and Keratin.

BiotinThe pick
Limited evidence · 2500 mcg
Vitamin B7 and cofactor for carboxylase enzymes in fat and amino acid metabolism; deficiency causes hair thinning and skin rash.
KeratinThe pick
Limited evidence · 500 mg
Fibrous structural protein that forms hair, nails, and the outer skin layer; taken to support hair strength and reduce nail brittleness.

Buy the #1 pick

The dose“Is the dose actually effective?”

Dose-range data is not available for this formula yet.

Biotin

Studied window 2500-5000 mcg · this pick 2500 mcg

Keratin

Studied window 500-500 mg · this pick 500 mg

13.7 mg

2500 mg

1.6 mg

18 mg

2 mg

1.5 mg

15 mg

The ranking“Why should I trust this pick?”

Strong trust signals — consistently high marks from verified buyer ratings. Each product gets a DoseRank score blending clinical strength, evidence, dose fit, trust and value. Retailer links may be affiliate links — the scoring model decides placement, never payment from a brand.

2,219 products scored
Never paid placement
Evidence level: Limited · 60
288 brands
6 ingredients

See the full analysis — every score, every product How the ranking works

The price“Can I do better than $0.74 a serving?”

$0.74 per serving — high price tier for this outcome. The cheapest ranked pick here is $0.06 per serving.

9
Nutricost, Biotin, 10,000 mcg, 240 CapsulesScore 85 · $0.06/serving
iHerb
4
21st Century, Biotin, 360 TabletsScore 86 · $0.06/serving
iHerb

Why not the absolute cheapest? The DoseRank score also weighs clinical strength, evidence, dose fit and trust — the very cheapest listings rarely hold up everywhere else.

Ready?

The #1 pick is $0.74 a serving.

Life Extension, Hair, Skin & Nails, Collagen Plus Formula, 120 Tablets — in stock at a tracked retailer.

View on iHerb

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Questions

Frequently asked

Life Extension, Hair, Skin & Nails, Collagen Plus Formula, 120 Tablets ranks #1 for Nail strength with a DoseRank score of 87. The score blends clinical strength, evidence, dose fit, trust signals and value across 2,219 products scored for this outcome.

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Other outcomes

Nail brittlenessFragility or easy breakage of nails.

Frequently asked