If you have colored hair, you likely already understand the importance of using color-safe formulas to protect your hue. What you may not know is that your hair's pH can also have a notable impact on your color's vibrancy and lifespan. That's where acidic haircare products can come into play. Acidic products work to seal your hair’s cuticle, keeping your color locked in long after you leave the salon.
We chatted with Matrix colorist George Papanikolas and Agathe Lahaye, the Vice President of L’Oréal’s Hair Color Research & Innovation team, to get the scoop on acidic haircare. Ahead, learn more about hair pH and how it can affect your hue, and which L'Oréal professional products can help prolong the life of your color.
Why is hair pH important?
Before we dive into acidic haircare, let’s take a quick trip back to Chemistry 101 and revisit the pH scale. This scale measures the acidity or alkalinity of objects from zero to 14. The lower the number, the more acidic a substance is: zero through six is acidic, seven is neutral, and eight to 14 is alkaline (or basic).
Hair in its natural, healthiest state is slightly acidic, but chemical, mechanical, and environmental damage can cause hair to become more alkaline. Too much alkalinity can raise the hair’s cuticle and, in terms of color, allow dye molecules to escape, ultimately resulting in a faster color fade.
Photo credit: @kaciedoeshair_
What is acidic haircare?
Acidic haircare products help to restore your hair’s natural acidity, which allows it to hold onto hair dye more effectively. More specifically, Lahaye explains that acidic haircare “refers to products with a pH level below seven” that closely align with hair’s natural acidity. These products help re-seal the hair’s cuticle so it’s smoother and tighter, which can help prevent hair color from leaching out. The smoothing effect also allows light to reflect off the hair’s surface, giving your locks a shiny, glossy finish.
The benefits don’t end there, though: Layahe notes that sealing the cuticle can also help the hair retain essential moisture, making it less prone to concerns like breakage and frizz.
How do you find acidic hair products?
As with most haircare concerns, your first course of action when building a new routine should be to text your stylist. They can tell you if acidic haircare suits your particular hair type and color. If you’re not on meme-swapping terms, a standard consultation appointment or call to the salon will work just as well.
Some salon-grade hair products list their pH right on the packaging, making it easier for you to identify on store shelves. Papanikolas recommends looking for color-safe formulas that have a pH between 3.5 and 5.5. As mentioned, a lower pH number indicates a higher acidity, which preserves hair’s integrity by opening the cuticle less (that’s the goal, after all).
Pro-Approved Acidic Formulas to Try
If you’re in the market for acidic formulas to consider, our experts shared their top picks from L’Oréal’s portfolio of professional brands.
Redken Acidic Color Closs
The Acidic Color Gloss collection is a salon-inspired home glossing range that extends color, conditioning, and shine between salon appointments.
“[Acidic Color Gloss is] designed to retain and deposit shine, keeping color-treated hair vibrant and glossy,” says Lahaye. “It’s like giving your hair a little shield that makes it look fabulous and brings it closer to its natural, healthy state.”
The four-part system features a shampoo, conditioner, and leave-in spray, but Layahe says the Activated Glass Gloss Treatment is the true star of the line. The pH-balanced formula can give hair intense shine for up to three days* and “works wonders on all hair types for a dazzling sheen.”
*Based consumer test, Activated Glass Gloss Treatment
Matrix Keep Me Vivid
Papanikolas’ choice for color-treated hair is Matrix’s Keep Me Vivid Color Lamination Spray, which he says “falls on the lower end of the spectrum with a pH of 4.0-5.0.” He emphasizes that acid sprays are typically salon-only formulas but loves that this one is accessible to consumers.
The formula is fit for different points in your hair color journey: Your stylist can use it immediately post-color service, or you can take it home to extend your color vibrancy for up to 21 washes. To get the benefits, spritz the Lamination Spray onto your hair after using the Keep Me Vivid Shampoo. Let it sit for one minute, then layer it with Keep Me Vivid Conditioner. Rinse your hair and style as usual.
Biolage Professional Color Acidic Milk Rinse
When you want to sit back and let a professional take control, ask your salon if they offer Biolage Professional’s Color Acidic Milk Rinse. This salon-exclusive hair rinse smooths the cuticle, enhances color vibrancy and rebalances hair’s pH. Plus, the formula is infused with oat and coconut milk to help leave hair soft and silky.
Who should try acidic haircare?
Ultimately, Papanikolas says, acidic haircare is ideal for anyone who wants to protect and care for their color-treated hair. “The low pH formula will seal the color into the hair, giving you a richer and more vibrant color with lots of shine.”
When in doubt, ask your stylist about adjusting your haircare routine to involve more acidic formulas. You may be pleasantly surprised at how much of a difference it can make.
Next Up: Everything You Need to Know About Redken’s Acidic Haircare Lines
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