Many people with dark hair who want to go blonde opt to get a double process, which involves both lightening and toning the hair in one salon visit. While double processing can achieve drastic color results quickly, it does put significant stress on the hair. Understanding the risks and proper aftercare can help minimize damage from double processing.
What is double processing?
Double processing refers to lightening and toning hair in the same appointment. This involves applying lightener to lift the underlying pigment, rinsing, then applying toner to neutralize unwanted tones and deposit the desired shade.
For brunettes going blonde, a double process is usually required to reach platinum or extra light shades in one session. Dark hair has more underlying pigment, so lightening alone often results in orange or brassy tones. The toner is necessary to counteract those warm tones and achieve an icy blonde.
Doing two chemical services back-to-back allows the colorist to dramatically lighten and alter the hair color in a short timeframe. However, the combined chemicals make it very taxing on the hair’s structure.
Risks and dangers of double processing
While double processing allows faster, more radical color transformations, it comes at a cost. Some risks and dangers include:
- Extreme dryness and damage – Lightener opens the cuticle and removes pigment, while toner re-deposits artificial pigment. This level of chemical penetration leads to desiccated, fragile strands.
- Increased risk of breakage – The harsh process leaves hair severely compromised and prone to snapping off.
- Loss of elasticity – Chemical processing can degrade the disulfide bonds in keratin, causing strands to lose their stretch and resiliency.
- Weakened, thinning hair – Overprocessing causes cumulative damage that steadily diminishes the integrity and diameter of each strand.
- Scalp irritation – The combination of chemicals can inflame the scalp, causing redness, itching, and tenderness.
- Hair loss – Repeated chemical trauma can impair the growth cycle and lead to shedding or bald patches.
Is double processing always bad?
How damaging a double process is depends on several factors:
- Hair health and history – Hair in poor condition or previously damaged from chemicals is more prone to injury during double processing.
- Desired color level – The lighter the target shade, the more intense the lightening step will be.
- Hair type and texture – Fine, fragile, or highly porous hair tends to sustain more chemical damage than coarse, dense hair.
- Products used – Gentler formulas with reparative oils and natural extracts can help mitigate damage.
- Stylist expertise – An experienced colorist will evaluate hair and use precise technique to avoid overlap and unnecessary stress.
- Post-salon care – Proper at-home conditioning and protective styling helps combat chemical effects.
When done with care on healthy virgin hair, a double process may only cause minimal damage. But repeatedly double processing fragile, chemical-treated hair can severely compromise integrity over time.
Can you double process at home?
It’s not advisable for beginners to attempt double processing at home. Improper application and overlapping lightener with toner can quickly lead to chemical burns and disastrous results.
If you insist on DIY double processing:
- Do a strand test first to gauge lift and timing.
- Carefully follow all instructions and never overlap lightener with toner.
- Use a timer and check frequently to avoid overprocessing.
- Have someone help you apply to the back sections thoroughly.
- Opt for an ammonia-free, conditioning lightener formula.
- Use a toner with a low-volume developer to minimize further damage.
- Focus on conditioning and hydrating for weeks afterward.
Getting professional help reduces the risks of a botched home double process. But if you take great care, monitor development, and avoid overlap, it may be possible. Be very cautious and prepared for a long repair process if hair sustains significant damage.
Can you double process at home?
It’s not advisable for beginners to attempt double processing at home. Improper application and overlapping lightener with toner can quickly lead to chemical burns and disastrous results.
If you insist on DIY double processing:
- Do a strand test first to gauge lift and timing.
- Carefully follow all instructions and never overlap lightener with toner.
- Use a timer and check frequently to avoid overprocessing.
- Have someone help you apply to the back sections thoroughly.
- Opt for an ammonia-free, conditioning lightener formula.
- Use a toner with a low-volume developer to minimize further damage.
- Focus on conditioning and hydrating for weeks afterward.
Getting professional help reduces the risks of a botched home double process. But if you take great care, monitor development, and avoid overlap, it may be possible. Be very cautious and prepared for a long repair process if hair sustains significant damage.
Aftercare tips for double processed hair
To combat the drying, damaging effects of a double process, incorporate restorative steps into your routine:
- Use a deep conditioning hair mask 1-2 times per week.
- Shampoo less frequently, every 3-4 days, to avoid over-stripping oils.
- Rinse with cool water and use minimal heat styling.
- Get occasional reparative salon treatments like Olaplex or Brazilian Blowouts.
- Use a leave-in conditioner and heat protectant before hot tools.
- Sleep on a silk pillowcase to minimize overnight friction.
- Get regular trims to remove split ends before they travel up the shaft.
- Consider a short, chin-length cut to remove the most damaged lengths.
While discipline with aftercare can help restore some health, severely processed strands will remain fragile. Be extra gentle and avoid chemical services until hair is strong enough.
When to avoid double processing
Those at great risk of intense damage should not double process hair:
- Children or teens under age 16
- Pregnant or breastfeeding women
- People with sensitivities or scalp conditions
- Individuals with very fine, porous, or fragile hair
- Anyone with hair previously damaged from chemicals or heat styling
- People wanting to go more than 3-4 levels lighter
In some cases, spacing out lightening and toning into two separate appointments may be safer. While slower, it gives hair recovery time between chemical services.
Double process vs. highlights: Which causes more damage?
In general, double processing all over puts more stress on hair than highlights. Here’s a comparison:
| Double Process | Highlights | |
|---|---|---|
| Lightening | Applied evenly to all hair | Applied only to thin strands |
| Toning | Coats all hair to desired shade | Usually not needed |
| Results | Uniform color transformation | Gradual, natural-looking lightness |
| Damage level | High – Chemicals penetrate all hair | Lower – Less chemical interaction |
However, heavily highlighted hair can also sustain significant cumulative damage over time. Both processes require caution to avoid breakage and maintain condition.
Conclusion
While double processing allows for dramatic, fast color makeovers, proceeding with caution is crucial. On healthy, virgin hair, permanent damage may be minimal if proper technique is used. But the repeated use of overlapping chemicals risks major structural degradation of strands.
To make an informed decision, understand your hair’s current state and how much risk it can withstand. Be realistic about the level of blonde you can achievable in one session. And invest in restorative salon treatments and at-home conditioning to combat the drying effects.
While double processing is not universally damaging, it should not be taken lightly. Being selective about when to employ this intensive chemical process can help preserve your hair’s health and integrity long-term.
