How Long a Perm Will Last
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If you keep the hair well-conditioned, you can easily expect the body wave to look good for about 8-12 weeks.
Body waves have the same risk of drying out the hair as regular perms since they use the same basic formulation and raise the cuticle layer in order for the perming solution to penetrate into the shaft. This makes the hair more porous and likely to lose moisture.
Keeping the hair conditioned will make sure the hair stays smooth, and will keep the wave looking good.
©Hairfinder.com
See also:
Perms
Are permanent curls right for you?
Is there such a thing as a semi-permanent perm?