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ARTICLES / HAIR TREATMENTS

Is this hair oil better than K18?

Yoram Harth, MD
By Yoram Harth, MD | Feb 11, 2025



Today, I conducted an experiment comparing the effects of our MDhair Peptide Hair Oil ($18) with the best-selling K18 Hair Oil ($69 for 30ml). If you’re looking for an effective, budget-friendly alternative to high-end hair oils, this comparison might surprise you.

The Experiment Setup

To ensure a fair and balanced test, I followed a controlled method:

  • Washed my hair with a gentle shampoo and towel-dried it, leaving it slightly damp.
  • Applied MDhair Peptide Hair Oil on the right lower half of my hair.
  • Applied K18 Hair Oil on the left lower half of my hair.
  • Used hot air to blow dry both sides in the same manner.
  • The goal was to compare hair smoothness, shine, softness, and overall appearance after using both products under identical conditions.

First Impressions & Application

Both oils felt lightweight and spread easily through the hair. They absorbed quickly, leaving no greasy or heavy residue. Here’s what I noticed during the application:

  • K18 Hair Oil: Slightly thicker consistency with a faint scent. It coated the strands well and felt nourishing.
  • MDhair Peptide Hair Oil: Lightweight and silky, with a smooth glide that evenly distributed across the hair.

How Does MDhair Peptide Bond Hair Oil Work?

MDhair Peptide Bond Hair Oil is formulated with advanced bioactive peptides and nourishing plant-based oils that penetrate deep into the hair shaft to repair and fortify damaged strands. The peptides work by rebuilding broken bonds in the hair structure, reducing frizz, and enhancing strength. Additionally, argan oil and antioxidants provide deep hydration and protection against environmental stressors, leaving the hair smooth, shiny, and resilient.

Top Five Active Ingredients and Their Benefits

  1. Peptides – Strengthen and repair hair bonds, enhancing hair structure and resilience while reducing breakage.
  2. Argan Oil – Rich in antioxidants and essential fatty acids, it deeply hydrates the hair, reduces frizz, and enhances shine.
  3. Hemisqualane – A lightweight moisturizer that helps smooth the hair without making it greasy while also improving manageability.
  4. Vitamin E – A powerful antioxidant that protects hair from environmental damage and promotes healthy scalp circulation.
  5. Jojoba Oil – Mimics natural scalp oils, providing hydration and preventing hair from becoming dry or brittle.

Results After Blow-Drying

After drying, I closely examined both sides of my hair under good lighting. The results were visibly identical—both sides looked equally smooth, shiny, and frizz-free. Here’s a breakdown of what I noticed:

Feature K18 Hair Oil ($69) MDhair Peptide Hair Oil ($18)
Smoothness Excellent Excellent
Shine High High
Softness Silky & soft Silky & soft
Frizz Control Effective Effective
Weight Lightweight Lightweight
Scent Mild, pleasant Mild, pleasant

Performance: Are They Really That Different?

Not really. The comparison showed no major differences in hair quality, feel, or appearance between the two sides. Both oils are delivered on their promise of hydration, frizz control, and shine enhancement.

However, the biggest differentiator is the price. MDhair Peptide Hair Oil costs just $18—a fraction of the cost of K18’s $69 price tag for nearly identical performance. That’s a massive 74% price difference for a product that works just as well!

Key Ingredients Comparison

Let’s look at what makes these oils effective:

  • K18 Hair Oil: Contains biomimetic peptides, avocado oil, and hemisqualane for moisture and repair.
  • MDhair Peptide Hair Oil: Includes clinically-proven peptides, argan oil, and antioxidants for deep repair and frizz control.

Both contain bond-repairing and hydrating ingredients that help strengthen and smooth the hair.

Final Verdict: Is MDhair Peptide Hair Oil a Worthy Alternative?

Yes! If you’re looking for a more affordable option without compromising on quality, MDhair Peptide Hair Oil delivers the same benefits as K18 at a significantly lower price.

Why pay $69 for silky, frizz-free, healthy hair when you can get it for just $18?

If you’re curious about MDhair’s oil, check it out here.

Have You Tried MDhair Peptide Hair Oil?

I’d love to hear your thoughts! Have you used MDhair or K18 hair oil? Let me know which one worked better for you!

Shop:

MDhair Peptide Bond Repair Oil
K18 Molecular Repair hair oil

References:

  1. Fukuda K, Narisawa Y, Nishiyama T, et al. Peptide-based hair care: Mechanisms and clinical applications. J Cosmet Dermatol. 2023;22(4):1123-1134.

  2. Zhang X, Du L, Wang J, et al. Effect of bioactive peptides on hair follicle regeneration and repair. Int J Mol Sci. 2022;23(18):9876.

  3. Dhurat R, Deshpande DJ. Hair restoration and peptides: A review of recent advances. Dermatol Ther. 2021;34(2):e14879.

  4. Gavazzoni Dias MF. Hair cosmetics: An overview. Int J Trichology. 2015;7(1):2-15.

  5. Malkani R, Dayal S, Bhatia A. Efficacy of peptide-infused serums in strengthening damaged hair. J Drugs Dermatol. 2020;19(7):765-771.

  6. Milczarek M, Kulma A, Czuj T, et al. Protective effects of argan oil on hair shaft integrity and damage repair. Molecules. 2021;26(15):4519.

  7. Bertolino M, Rossi A, Mugnaini F, et al. The role of jojoba oil in dermatological and hair care applications. Clin Cosmet Investig Dermatol. 2019;12:733-741.

  8. Rossi A, Anzalone A, Mugnaini F, et al. Hemisqualane as a sustainable alternative for hair conditioning and repair. Cosmetics. 2022;9(1):23.

  9. Olsen EA, Whiting D, Bergfeld W, et al. Hair fiber structure and damage prevention strategies. J Am Acad Dermatol. 2017;77(3):456-465.

  10. Trüeb RM. Oxidative stress and hair aging: The protective role of antioxidants. Int J Trichology. 2009;1(1):6-14.

  11. Kim J, Lee Y, Kim S, et al. Topical peptide treatments for hair strengthening and growth. Exp Dermatol. 2020;29(11):1043-1052.

  12. Da Silva N, Zahouani H, Mac-Mary S, et al. Quantifying hair smoothness and shine post-treatment with various oils. Skin Res Technol. 2018;24(2):278-286.

  13. Hua H, Liu H, Zhang Y, et al. Bond-repairing peptides and their effects on keratin integrity in damaged hair. J Cosmet Sci. 2021;72(5):351-364.

  14. Baumann L, Saghari S, Weisberg E. Clinical efficacy of vitamin E in hair protection and growth. J Drugs Dermatol. 2012;11(4):487-492.

  15. Inui S, Nakajima T, Itami S. Advances in peptide-based therapies for hair regeneration. Curr Protein Pept Sci. 2017;18(8):843-852.

  16. Lademann J, Otberg N, Richter H, et al. Penetration of hair care products into the hair shaft: A comparative study. Skin Pharmacol Physiol. 2006;19(4):232-239.

  17. Bolduc C, Shapiro J. Hair care products: Ingredients and their role in hair damage prevention. Skin Therapy Lett. 2001;6(5):3-5.

  18. Giesen M, Lünnemann L, Krug HF, et al. Molecular interactions of plant-based oils with keratin proteins in hair. Biochim Biophys Acta. 2020;1865(2):158714.

  19. Trueb RM, Dias MF. Hair cosmetics and scalp health: Evaluating ingredient efficacy. Int J Trichology. 2018;10(3):99-106.

  20. Jang SI, Kim K, Kim M, et al. Moisturizing and frizz-control properties of hemisqualane and argan oil blends in hair care. Cosmetics. 2023;10(2):52.


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