TLDR A new 6-point scale reliably measures heat damage to hair from styling tools.
The study addresses the lack of a standardized method for measuring heat damage to hair caused by styling tools. Researchers propose a 6-point heat damage scale based on single-fibre tensile strength measurements, focusing on 8 wet tensile parameters. This scale is designed to be robust, reproducible, and relevant to consumers. The study demonstrates a strong correlation between the technical damage scale and human perception of hair damage, validating its applicability to various heated hair straighteners on the market. The research was conducted by Good Hair Day (GHD) and funded internally, with data available upon request.
13 citations
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March 2019 in “Journal of cosmetic dermatology” Heat damages hair, with Asian hair losing more protein than Caucasian hair.
175 citations
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January 1995 in “Birkhäuser Basel eBooks” Human hair growth and structure are influenced by keratin proteins, genes, melanin, and lipids.
January 2017 in “Clinical approaches and procedures in cosmetic dermatology” Cosmetic procedures can harm hair, but damage can be minimized with knowledge and care; however, once hair is damaged, it cannot be reliably repaired.
October 2024 in “Cosmetics” ATG effectively reduces hair frizz without damaging hair strength.
December 2025 in “Biopolymers” Heat worsens damage in chemically treated hair, especially bleached and straightened hair.
3 citations
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February 2023 in “ACS omega” Grape seed oil improved hair quality the most, followed by rosehip and safflower seed oils, and reduced damage from shampoo.
1 citations
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January 2017 in “Clinical approaches and procedures in cosmetic dermatology” Hair can't be reliably repaired once damaged; prevention and proper product use are key to maintaining hair health.
