“Is It Really Best for a Straight Perm to Last as Long as Possible?”

Before and after of a straightening treatment. Left: wavy and frizzy hair. Right: naturally smooth and straight hair. Photo taken in a salon with large windows overlooking the city.

Is It Really Best for a Straight Perm to Last Long?

“It’s better if it lasts a long time, right?”
This is something I often hear—not just about straightening, but also about cuts and perms in general.

But actually, “long-lasting equals better” isn’t always true.

In this post, I want to focus specifically on straightening and share my thoughts.

There Are Two Main Types of Straightening Treatments

When people in Japan hear the word “straightening,” they often think of:

Japanese straight perm (shukumoukyousei)
Straight perm
Hair texture improvement
Acid straightening
Acid heat treatment, etc.

But broadly speaking, they fall into two categories:

① Straightening with chemicals + flat iron
→ Japanese straightening / texture improvement / acid straightening / acid heat treatment

② Straightening with chemicals only
→ Standard straight perm

What I usually recommend is the latter: straightening without using a flat iron.

Non-Long-Lasting Straightening = Natural, Low-Maintenance Style

Straightening with a flat iron has the advantage of completely straightening even strong curls, and it lasts long.

However, it also has these drawbacks:

New hair growth makes the difference at the roots obvious
Busy people often end up looking like they haven’t maintained their hair
The ends can look unnaturally stiff
It’s hard to return to your natural hair once done
It causes heavy damage, making it hard to combine with coloring or perms

In contrast, non-flat-iron straightening that lasts about 1–3 months has these benefits:

Natural blend between roots and ends
The overall balance stays better even as it grows
You can return to your natural texture over time
Easy maintenance and still looks “neatly done”
Less damage, so it works well with coloring and perms

Of course, depending on your hair type, some wave may remain if no iron is used.
Still, when considering the overall pros and cons, I often recommend it—especially for busy people.

“Hair Texture Improvement = Healthier Hair” Isn’t Quite Accurate

These days you often see terms like “hair texture improvement” or “acid heat treatment.”

The names might make you think, “It’s just a treatment that makes your hair healthier,”
but in reality, they are straightening methods that use both chemicals and heat—just like Japanese straightening.

They’re not all bad, of course, but…

Sometimes it’s advertised as ‘makes your hair shiny,’ but in fact, it causes strong damage…

This is not uncommon.
That’s why it’s important to understand the actual procedure instead of being misled by names or images.

Softness and Styling Ease Are Also Big Advantages

Straightening without a flat iron may leave a bit of wave.
But on the flip side…

Your hair stays soft and flexible
It retains some volume, making it easier to manage
It pairs well with coloring or perms

You don’t have to worry as much about things like:
“If I get a straight perm, I probably can’t get a perm or color anymore…”

Choose What Suits Your Lifestyle

There are certainly people who benefit from long-lasting straightening.
But the opposite is also true—“Not lasting too long can actually help you stay naturally beautiful.”

For example…