Can heat damaged hair be reversed? Jamien Lim, Senior Hair Research Scientist from Dyson says, “To simply answer the question, heat damage is irreversible. Once the protein bonds are broken and the hair cuticles are cracked, the inner cortex is exposed to all types of damage which makes it weaker and less pliable.”

Due to heat, hair strands start to split at the ends where the hair is oldest and has experienced the most damage, but those splits can move up the hair shaft splitting multiple times, making the damage worse. Because the hair has lost its elasticity, the strands are more susceptible to breakage. When the hair becomes too weak, the ends will snap off, which will eventually lead to fly aways.

While it is irreversible, Jamien Lim, Senior Hair Research Scientist from Dyson answers some important questions about heat damage.

What causes heat damaged hair?

Heat damaged hair occurs when you blow dry your hair,or usea flat iron, or curler at the highest temperature settings over an extended period while styling your hair. Most hot tools reach temperatures of more than 400°F, which affect all types of hair types starting from pin straight to tightly curled.

Why is hair heat damage irreversible?

Each strand of hair is made up of a protein known as keratin that has a natural curve called the alpha helix. This is present in both curly hair and straight hair. High temperatures permanently alter the structures of the protein bonds in one’s hair.

When the keratin is heated to temperatures higher than 400°F, the alpha helix begins melting. Once the alpha helix is melted, the change is permanent, and the hair will retain the shape of the melted keratin bonds.Once the hair starts growing past the follicle, it's made up of dead cells. Because of this, the cells can't adapt, and when they're changed, it's permanent. There are no active cells that can be sent in to repair the damage.

The damage done to the hair is cumulative. The chances to experience heat damaged hair after one blow dry or one straightening session are slim. However, using hot tools at high temperatures on a regular basis prolongs the changes to the protein bonds and moisture levels of each strand. If you continue using hot tools, the damage progresses as well.

Eight Signs of heat damaged hair

Dryness and dullness

The cuticles of your hair are whatmakeit shiny. When the cuticles are damaged, the hair loses its shine. After the hair wash, the hair should look brighter and shinier than it was. If it's dull, that's one of the first signs of heat damaged hair. Dryness also contributes to dull hair. Damaged hair doesn't properly maintain moisture, leaving the tresses dehydrated and prone to breakage.

Split ends & Breakage

Heat damaged hair loses elasticity because applying heat on a regular basis affects the hair’s ability to retain moisture, often resulting in split ends. Split ends weaken the structure of the hair, which increases the chances of hair breakage. Exposing hair to frequent high heat also increases the risk of breakage because it loses its elasticity.

Flyaways

Flyaways are often a sign of breakage and are short hair strands that stand up after breaking off near the roots. Flyaways can be difficult to manage and tame and can affect the overall look of the hair, especially if one is trying for a sleek and polished style. Use the Airwrap multi-stylerTM flyaway attachment to tame those flyaways, especially during the monsoon season.

Rough or changed texture

To determine if the texture has changed, one can run the fingers through the hair. Heat damaged curly hair may lose its spring and not bounce back the way it did when the hair was healthy. Damaged straight hair can go from feeling smooth and silky to feeling rough and coarse. You may even describe heat damaged hair as feeling frayed or singed at the tips.

Knots and tangles

Hair cuticles are made up of “shingles”. When the hair cuticles become damaged, the shingles begin to stick out, causing strands of hair to easily knot with other strands. Knots and tangles make brushing or combing the hair more difficult and can lead to further breakage.

Incorrect hair colour

Heat damaged hair can't properly retain colour. If your hair has become too porous, it might absorb too much of the dye and make the colour darker than you have desired for. Your hair colour might also fade faster than normal as damaged hair has high porosity, it releases more colourduring hair wash.

Hair loss

The average person has approximately 80,000 to 120,000 hairs on their head. Hair strands grow for 2 to 6 years, and it's normal to shed hairs. During these 2 to 6 years, strands collect damage. If one has heat damaged hair, the strands are weaker therefore, one might witness more hair loss.

As it is established that damaged hair repair isn't possible because the protein bonds and cuticles have been permanently altered. Knowing the signs of heat damaged hair will help you determine if that's what you're dealing with, and it allows you to start taking steps to get your hair in a healthy state once again.

Source - IANS