Ammonia is a chemical commonly found in hair dye that helps open the hair cuticle so the color can penetrate the hair shaft. However, ammonia has gotten a bad reputation, with some believing it damages hair. This has led to an increase in ammonia-free hair colors on the market. But is ammonia-free hair color actually better for your hair? Here’s a look at the pros and cons of ammonia hair color.
What is ammonia and why is it used in hair color?
Ammonia is a colorless gas that is used to create alkaline conditions. In hair color, ammonia:
- Swells the hair cuticle so dye molecules can penetrate the cortex where pigment is deposited
- Lifts the cuticle so natural pigment can be removed from hair
- Helps dye spread evenly through the hair
By raising the pH and swelling the cuticle, ammonia allows permanent hair color to deposit or remove pigment for predictable, even results. The amount of ammonia in hair dye ranges from 1% to 10%. Higher levels are used in hair lighteners.
What are the concerns about ammonia in hair dye?
There are a few main concerns about ammonia in hair color:
- Irritation – Ammonia has an unpleasant, strong odor that can irritate the eyes, skin, and respiratory system.
- Hair damage – Some claim high levels of ammonia overprocess hair, leaving it dry and brittle. However, reputable studies have not found a link between ammonia and hair damage at the levels used in hair dye.
- Allergic reactions – Ammonia is a known allergen. Those with sensitive skin may experience redness, itching, or burning from ammonia-containing dyes.
While an annoyance for some, ammonia itself is not considered dangerous at the concentrations present in hair color when used as directed. Still, people looking to avoid potential irritation or allergic response may want an ammonia-free option.
What are the pros of ammonia-free hair dye?
Going ammonia-free offers some benefits:
- Reduced odor – Ammonia produces a strong, unpleasant smell some find overwhelming.
- Less irritation – Lower risk of eye, skin, or respiratory irritation in sensitive individuals.
- Gentler feel – Some report ammonia-free colors feel less harsh on hair and scalp.
- Shorter processing – Removing ammonia may shorten application and development time.
Many seeking an ammonia-free alternative like the idea of a formula that is gentler on hair. However, there are some downsides.
What are the cons of ammonia-free hair color?
While ammonia-free hair dye seems ideal, there are a few potential drawbacks:
- Less lifting power – Ammonia-free colors have less ability to lighten hair. They work best for darker colors or touch-ups.
- Shorter lasting color – Removing ammonia may produce color that doesn’t last as long or fades faster.
- Inconsistent coverage – Lack of cuticle penetration can lead to uneven color results.
- Premature fading – Some ammonia-free dyes wash out quickly and leave hair brassy.
Formulating permanent hair dye without ammonia is challenging. While irritation may be reduced, the trade-off is color performance in many cases.
How does ammonia-free hair color work?
Permanent hair color uses a two-step process – first opening the cuticle, then depositing color inside the hair shaft. Ammonia-free formulas take a few approaches:
- Monoethanolamine (MEA) – This ammonia substitute still swells the cuticle but is less alkaline. However, it may cause similar irritation.
- Amino acids – Gentler amino acids found in hair proteins help lift cuticles. Performance is milder than ammonia.
- Oils – Some oils can penetrate hair without needing to lift cuticles as much. However, results are less consistent.
- Heat – Warming the color during application aids cuticle swelling and dye penetration without ammonia.
While these alternatives can reduce the need for ammonia, they may not achieve the same level of cuticle lifting and color penetration. More passes may be needed to get the desired result.
Are ammonia-free hair colors less damaging?
Since ammonia itself is not considered damaging at the levels used in hair dye, ammonia-free colors don’t necessarily cause less damage. However, some other differences may have an effect:
- Lower peroxide levels – Some ammonia-free dyes use less peroxide, which causes oxidative damage during lifting.
- Shorter processing – With less time on hair, there is less opportunity for damage to occur.
- Gentler ingredients – Replacing harsh ammonia with oils and amino acids is intrinsically gentler.
Any reduced damage is likely due to shorter processing and the use of gentler substitute ingredients. However, this gentleness usually comes at the cost of less lightening power and longevity.
What’s the difference between semi-permanent and ammonia-free permanent color?
It’s easy to confuse semi-permanent and ammonia-free permanent hair dye. The main differences are:
|No lifting of natural pigment
|Can lighten hair slightly by swelling cuticle
|Small color molecules sit on outside of hair
|Larger color molecules penetrate hair shaft
|Washes out over 4-8 weeks
|Lasts 4-6 weeks before fading
|No ammonia or peroxide
|Contains lower levels of one or both
While ammonia-free dye doesn’t last as long as a standard permanent color, it still has better longevity than a true semi-permanent which sits only on the hair surface.
Is professional ammonia-free color better than boxed?
Both boxed and professional ammonia-free hair colors reduce or remove ammonia content. However, professional dyes offer some advantages:
- Lower ammonia – Professional brands can formulate with little to no ammonia.
- Alternatives – Salons have access to high-tech ammonia alternatives not found in boxed dyes.
- More shades – Professionals offer a wider range of colors to customize results.
- Expert application – Cosmetologists are skilled at technique to maximize color penetration.
With knowledge of hair properties and access to advanced ingredients, a professional stylist can offer ammonia-free color with better results than a boxed kit at home.
What’s the bottom line on ammonia-free hair color?
Here are some quick takeaways on the pros and cons of ammonia-free dye:
- Less odor and fumes
- May be gentler on hair
- Reduced irritation for sensitive scalps
- Less reliable lightening ability
- Color may fade faster
- Can be more difficult to apply evenly
Ammonia-free colors provide an option for those seeking to avoid odor and potential irritation. However, removing ammonia means accepting some reduction in performance. For reliable results with minimal odor, consult a professional stylist about the best ammonia-free permanent color and application techniques for your hair.
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