Choosing a hair product usually comes down to what you want it to do for you.
When you're comparing a concentrated leave-in serum with a colour-depositing shampoo, you're really choosing between two different jobs: supporting hair density and covering grey. If your primary goal is a thicker, fuller look over time, you need one kind of routine. If you want to wash away grey quickly, you need another. Here's how to separate the two.
Quick Verdict
If you want to support your scalp and help hair look thicker and fuller over time, choose The Ordinary Hair Care Multi-Peptide Serum. If your main goal is grey coverage while you cleanse, choose Polar-Hair Dye Shampoo. These aren't competing versions of the same product; they're two different tools.
At a glance
| Product | Price | Format | Best for |
|---|---|---|---|
| The Ordinary Hair Care Multi-Peptide Serum | $15.49 | Leave-in scalp serum | Daily scalp care for fuller-looking hair |
| Polar-Hair Dye Shampoo | $9.99 | 2-in-1 colour shampoo | Quick grey coverage while cleansing |
Where each product wins
- The Ordinary Multi-Peptide Serum: A dedicated daily treatment with peptides and plant extracts, suited for people who want a targeted scalp step in their routine.
- Polar-Hair Dye Shampoo: A fast, convenient color-and-cleanse option that covers grey in about ten minutes and holds the colour for weeks with proper care.
Product notes
The Ordinary Hair Care Multi-Peptide Serum for Hair Density
This is a lightweight, concentrated leave-in serum. You apply a few drops to a clean, dry scalp once a day, preferably before bed, and massage it in. The active mix includes REDENSYL, CAPIXYL, caffeine, and plant extracts such as Larix Europaea Wood Extract and Pisum Sativum Extract, all chosen to support the scalp and help hair appear thicker and fuller. If you prefer a daily ritual that targets the scalp over time, this hair product is the one to use. It's also alcohol-free, sulfate-free, and vegan, which fits a clean-formula routine. The limitation: it won't cover grey, and it isn't a shampoo, so it adds a step to your routine rather than replacing one.
Polar Hair Dye Shampoo
Polar is a 2-in-1 shampoo that colours your hair while cleansing it. This version is Black, one of four shades available. It's designed to cover grey hair in as little as ten minutes and can keep a natural-looking colour for up to four to six weeks with proper care. For someone who wants a fast, no-mess way to refresh colour while washing, this is a practical pick. The formula uses natural botanical ingredients. The trade-off is that it doesn't offer the same peptide-focused scalp support as The Ordinary serum, so if grey coverage is the goal, a dedicated density treatment isn't part of this product.
Final choice by use case
- For hair density and scalp support: The Ordinary Hair Care Multi-Peptide Serum is the pick. Use it as a daily leave-in step.
- For grey coverage and quick colour: Polar-Hair Dye Shampoo is the pick. Use it when you want to cleanse and colour in one go.
