You're brushing hair WRONG! Wait 30 mins to comb after applying heat

"Heat makes hair temporarily much weaker and more brittle, they explained, which in turn makes it more likely to break under pressure. However, this effect is reversible - and all it requires is a little bit of patience. In their study, the researchers found that hair fully recovered when it was allowed to 'rest' for two hours after being straightened. But for those who don't have that much time to spare, waiting half an hour is also likely to be beneficial."

"Application of heat causes a dramatic reduction in performance...which is completely restored by a period of resting. This well-known effect, presumably due to dehydration and rehydration, is clearly and quantifiably demonstrated. For the study the team, from the University of Dublin, made a machine to reproduce what happens when you brush tangled hair."

"The individual hair strands are very thin and flexible, so they can literally tie themselves in knots - that's a tangle. When you brush your hair you force the tangle to move along the hair, down to the end. This puts huge stresses on the hairs, which can cause them to break or split. His team tested a range of different hair types including straight, curly, strong, treated hair prone to breakage and natural hair prone to breakage."

"Instead of pulling hair straight until it snaps, they used a 'moving loop fatigue test' to bend hair repeatedly and force it through a tight loop, simulating the repeated stress of tangled hair being brushed. Analysis revealed that heat makes hair temporarily much weaker. When hair was heated with straighteners at 150°C, the number of cycles it could withstand before breaking dropped dramatically."

Heat from straighteners temporarily reduces hair performance by making strands weaker and more brittle. The reduction is reversible after a resting period, with full recovery reported after two hours of rest. Waiting half an hour can also be beneficial. Brushing tangled hair forces knots to move toward the ends, creating large stresses that can cause breakage or splitting. A machine was used to reproduce brushing-related stress by repeatedly bending hair and forcing strands through a tight loop. Hair types tested included straight, curly, strong, treated hair prone to breakage, and natural hair prone to breakage. Results showed that heating at 150°C sharply lowered the number of cycles hair could withstand before breaking.

Read at Mail Online