Wet Hair Is Fragile: How to Dry It and Heat Temperature Guidelines

When hair absorbs water it swells, its hydrogen bonds break and it softens. Wet hair is weaker against pulling than dry hair, and with the cuticle open it is easily damaged by friction.

Towel-drying

Don't rub; press the hair between the folds of a towel. With a highly absorbent towel, most of the water comes out at this stage and blow-drying time is shorter.

Hair dryer

• Apply a leave-in treatment first to protect the surface from heat and friction
• Dry from the roots. Do the ends lightly at the end
• Keep the nozzle at least 15 cm from the hair and don't keep it on one spot, so the hair surface doesn't get too hot
• When hair is about 80% dry, finish with cool air. The hydrogen bonds set in that shape, giving shine and manageability
• Air-drying is not recommended because it lengthens the time hair stays wet and fragile

Flat irons and curling irons

Keratin is said to start denaturing at around 130–150°C, and above 180°C the effect becomes large even in a short time. Applying high heat to wet hair makes the water inside boil and breaks down the structure (bubble hair), so always dry hair first.

• Guideline: 140–160°C for fine or damaged hair; up to 160–180°C even for thick, healthy hair
• Don't pass over the same spot repeatedly. Divide hair into sections that need only one pass
• Even when using a heat-protecting leave-in, apply it, dry the hair, then use the iron

Related: Leave-in treatments / Beauty devices