The Complete Guide to Stronger, Healthier Nails — Backed by Research

The Complete Guide to Stronger, Healthier Nails — Backed by Research

Your nails say a lot about your overall health. Here's what the science suggests about keeping them strong, and what actually works.

Why Nails Break: The Basics

Nails are made primarily of keratin, a protein that also makes up your hair and the outer layer of your skin. Brittle nails — which affect up to 20% of the population — can result from frequent water exposure, harsh chemicals, nutritional gaps, or simply ageing.

Collagen and Nail Strength

One of the most cited studies on collagen and nails was published in the Journal of Cosmetic Dermatology. Researchers found that 24 weeks of oral bioactive collagen peptide supplementation led to a 12% increase in nail growth rate and a 42% decrease in broken nails (Hexsel et al., 2017, PMID: 28786550).

A 2024 double-blind trial confirmed these findings in a broader population, showing that collagen peptides were associated with visible improvements in both skin and nail appearance (Vleminckx et al., 2024, PMID: 39143887).

Supplements: What the Evidence Supports

A 2025 review in Skin Appendage Disorders examined the evidence for nail supplements, including collagen and biotin, and provided guidance on when supplementation may be appropriate for nail concerns (Zaraa & Richert, 2025, PMID: 40176998).

The review noted that while many nail supplements show promise, consistency over several months is key — nails grow slowly (about 3mm per month for fingernails), so visible improvements take time.

Cuticle Care: Don't Skip It

Your cuticles are the protective seal between your nail plate and the surrounding skin. Keeping them hydrated helps prevent hangnails, infection, and damage to the nail matrix (where new nail grows).

  • Moisturise daily — Apply cuticle oil before bed and let it absorb overnight
  • Push, don't cut — Gently push cuticles back after a shower when they're soft
  • Protect your hands — Wear gloves when washing dishes or using cleaning products
  • Stay hydrated — Internal hydration matters for nail moisture too

Products With These Ingredients

Adashiko Pure Collagen provides the same type of bioactive collagen peptides used in the Hexsel et al. (2017) study — 2.5g daily dose of hydrolysed collagen peptides. Adashiko Collagen Noni Gel combines marine collagen with noni fruit extract for topical nourishment. Verdo Cuticle Oil is an organic, NZ-made cuticle treatment that keeps cuticles hydrated — critical for protecting the nail matrix where new nail growth begins.

We've put together a Nail Care Routine that combines internal and external support:

The Bottom Line

Stronger nails come from consistent care — both inside and out. The research supports collagen peptide supplementation as a promising approach for nail strength, while simple habits like cuticle oil and hand protection make a meaningful difference day to day.

Individual results may vary. If you have persistent nail concerns, consult a dermatologist to rule out underlying conditions.

References

  1. Hexsel D, et al. (2017). Oral supplementation with specific bioactive collagen peptides improves nail growth and reduces symptoms of brittle nails. J Cosmet Dermatol. PMID: 28786550
  2. Vleminckx S, et al. (2024). Influence of collagen peptide supplementation on visible signs of skin and nail health. J Cosmet Dermatol. PMID: 39143887
  3. Zaraa I & Richert B (2025). Nail Supplements: When, How, and Why? Skin Appendage Disord. PMID: 40176998
  4. Colombo VE, et al. (1990). Treatment of brittle fingernails and onychoschizia with biotin: scanning electron microscopy. J Am Acad Dermatol. PMID: 2273113 | Google Scholar
  5. Chessa MA, et al. (2020). Pathogenesis, Clinical Signs and Treatment Recommendations in Brittle Nails: A Review. Dermatol Ther. PMID: 31749091 | Google Scholar
  6. DiBaise M & Tarleton SM (2019). Hair, Nails, and Skin: Differentiating Cutaneous Manifestations of Micronutrient Deficiency. Nutr Clin Pract. PMID: 31144371 | Google Scholar

Disclaimer: This article is for informational purposes only and does not constitute medical advice. Individual results may vary. Always consult a qualified healthcare professional or dermatologist before starting any new skincare treatment. Verdo Cosmetics makes no therapeutic claims about the products or services mentioned.

Frequently asked questions

What are nails actually made of?
Nails are made primarily of keratin, the same protein found in hair and the outer layer of skin. The article notes that brittle nails affect up to 20% of the population and can come from frequent water exposure, harsh chemicals, nutritional gaps, or ageing.
Does collagen help with nail strength?
The article cites a 2017 study in the Journal of Cosmetic Dermatology (Hexsel et al.) in which 24 weeks of oral bioactive collagen peptide supplementation was associated with a 12% increase in nail growth rate and a 42% decrease in broken nails. It frames this as research findings rather than a guaranteed outcome.
How long does it take to see a difference in nail health?
Because fingernails grow slowly, at about 3mm per month, the article explains that visible improvements take time and consistency over several months matters. The 2017 study it references ran over 24 weeks.
How should I care for my cuticles at home?
The article suggests moisturising daily by applying cuticle oil before bed and letting it absorb overnight, gently pushing cuticles back after a shower when they are soft rather than cutting them, wearing gloves when washing dishes or using cleaning products, and staying hydrated. It describes cuticle care as important for protecting the nail matrix, where new nail growth begins.
Where can I buy these nail care products in NZ?
The article mentions three products available through Verdo Cosmetics: Adashiko Marine Collagen Pure (a 2.5g daily dose of hydrolysed marine collagen), Adashiko Collagen Noni Gel (marine collagen with noni fruit extract for topical nourishment), and the organic, NZ-made Verdo Cuticle Oil. Verdo Cosmetics is located at 245 Parnell Road, Parnell, Auckland.
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