Abstract
Introduction
Hair plays a critical role in enhancing physical appearance, self-esteem, and identity. However, the impact of hair characteristics on daily life has received limited attention. This study aimed to assess the types and characteristics of hair, their variations according to age, gender, ethnicity, and country, and their effects on individuals’ daily lives.
Methods
A study was conducted between February 2022 and June 2023 across nine countries: USA, France, Brazil, India, China, Mexico, Japan, South Africa, and Indonesia. A total of 19,461 participants aged 18 and older were selected using stratified, proportional sampling. Participants completed a structured digital questionnaire evaluating hair thickness, type, damage, and curl degree, alongside questions on stress, sleep, and well-being. Data were analyzed using descriptive statistics and statistical tests (T-test, Pearson’s test).
Results
Thin hair was reported by 23.7% of males and 29.2% of females. Dry hair was more common in females (38.9%) than males (32.1%). Damaged hair was reported by 47% of females and 30% of males. Ethnic differences showed that thick hair was most common in African (40.7%) and least in Asian (26.3%) populations. The impact of hair type on daily life varied significantly across countries. Individuals with damaged or dry hair experienced higher stress, lack of sleep, and poor well-being, especially in Japan, India, and France. Hair type (straight, wavy, curly, kinky) also affected personal and professional stress levels differently in each country.
Conclusion
Our research shows that hair characteristics significantly influence daily life, self-image, and well-being, with notable variations by gender, ethnicity, and country. These findings highlight the need for interventions to address the psychological and social impacts of hair issues, contributing to better healthcare, body image, and product development.
Keywords: hair, impact on daily life, type, countries, region, quality of life
Introduction
Hair is considered to be one of the most important components of the beauty care processes and tends to attract the use of a variety of hair treating cosmetics.1 In fact, hair holds significant importance in the realm of beauty. It enhances physical appearance, expresses individuality and style, boosts confidence and self-esteem, and is a symbol of youthfulness and vitality.
In the field of dermatology, assessment of the impact on daily life is becoming an increasing interest in studies2–6 and remains important to estimate the burden of patients with skin conditions.7,8 Since hair beauty complements skin beauty by creating a cohesive and harmonious overall look that enhances natural beauty, it is equally important to evaluate the effect of hair conditions on daily life of individuals.
However, the impact of different hair types and characteristics on daily life of individuals has so far received minimal attention. Therefore, our objective was to perform the first international study that assesses types and characteristics of hair according to age, gender, ethnicity, and country, as well as their impact on daily life.
Materials and Methods
Population Selection
The survey was conducted by a polling company between February 2022 and June 2023 in USA [n=2512], France [n=1617], Brazil [n=2073], India [n=2960], China [n=2603], Mexico [n=2292], Japan [n=451], South Africa [n=2698] and Indonesia [n=2255].
The studied population was constituted of individuals aged 18 years and above, with around 3/4 females and 1/4 males, as this study was part of a larger international project on hair that focused on females, explaining the difference in proportions regarding gender. However, each of the male and female population of the study was a representative sample of the male and female population in each of the included countries. In fact, the selection used a stratified, proportional sampling with a replacement design.
In each of the countries in which it was conducted, proportional quota sampling was used based on the distribution of the population according to age, phototype, environment (large cities, towns, and rural areas), and income, in order to guarantee representativeness of the sample in each of the male and female group.
The eligibility of a respondent was based on demographic data, which were used to create a quota‐based sample. When a quota was filled, subsequent people in this category were no longer eligible.
Selected participants from all the respective countries were contacted by personal Email inviting them to take part in a survey without any specification of the subject of the survey. This prevented a self‐selection bias since participants with hair problems or concerns could have been more prone to participate in the study if its purpose had been disclosed. If contact was not successful, another potential participant with the same sociodemographic characteristics was randomly selected. To ensure the robustness of the data collected, individuals who did not complete the whole survey were excluded.
Questionnaire and Outcomes
Participants were asked to complete a structured digital questionnaire that evaluated patients’ 1) hair thickness: thick, thin, or no specificities, 2) hair type: dry, oily, or no specificities, 3) hair damage state: damaged or not, as well presence of some characteristics: frizzy due to humidity, difficult to smoothen, badly defined curls, too much volume, low density, split ends, dull without shine, hair loss, baldness 4) curl degree: straight, wavy, curly, and kinky. In order to specify the curl degree, participants were provided with a visual scale that represents the different curl degrees. We compared these types and characteristics according to age, gender, country and ethnicity (European, African, Hispanic, Asian, and other) (in countries where legislation permits to ask about ethnicity). We note that individuals in a same country can have different ethnicities and the same individual can have multiple ethnicities. We also asked participants whether or not they feel that they are stressed in their personal or professional life, tired, lack sleep, confidence, or cheerfulness, feel bad about themselves. We compared the impact on daily life according to thickness (thick vs thin), hair type (dry vs oily), hair damage state (damaged vs not damaged), damaged hair according to gender (damaged hair in males vs females), and curl degree (straight or wavy, curly, and kinky). Moreover, for damaged, oily, dry, and different curl degrees, we compared the impact on daily life among the different studied countries.
The questionnaire for data collection was designed in English by the scientific committee of the project which includes expert dermatologists and public health specialists. Once created, the questionnaire was administered to a small sample to ensure that they were properly understood. It was then translated into each language by native speakers living in the country concerned. To ensure linguistic similarity and cultural coherence between different language versions, the translations produced by native speakers were then “back‐translated” in English.
Statistical Analysis
Qualitative and ordinal variables were described by their number and frequency.
Results were tabulated in Excel and subsequently analysed. The student’s two-tailed T-test was used to determine statistical significance between groups. Pearson’s test was used to determine correlation. Results were considered statistically significant at a p-value <0.05.
The statistical analyses were carried out using the HARMONIE 1.7 software, registered with the INPI under the name DSE‐HARMONIE since 25 April 2013 with the registration number 4000937.
Ethics
The study has the following IRB number: 2023-A02701-44.
All participants provided informed consent, in accordance with the Declaration of Helsinki.
Results
In total, there were 19,461 participants in the study, of which 14317 (73.6%) females and 5138 (26.4%) males. The mean age was 39.7±13 y.o [median 40].
Thin hair was reported in 23.7% of males vs 29.2% of females (p <10−3). Thick hair was reported in 31.4% of males and females (p=0.9). Dry hair was reported in 32.1% of males vs 38 0.9% of females (p <10−3). Oily hair was reported in 12.9% of males vs 11.1% of females (p <10−3). Damaged hair was reported in 47% of females vs 30% of males (p <10−3). The comparison of types and characteristics of hair according to age and gender are represented in Table 1. Hair types and characteristics based on ethnicity are represented in Table 2. Thick hair was reported in 40.7% of African ethnicity and 26.3% of Asian ethnicity. Thin hair was reported in 34.7% of European ethnicity and 23.3% of Asian ethnicity. Dry hair was found in 46.7% of African, 33.2% of European, 35.8% of Hispanic, and 35.1% of Asian ethnicity. Damaged hair was reported in 47.6% of Asian ethnicity and 34.7% of European ethnicity. The impact on daily life of individuals according to hair thickness, oily/dry types, hair damage state, and curl degree is represented in Table 3.
Table 1.
Characteristics of Hair Based According to Age and Gender
| n | Female n=14317 | Male n=5138 | p value | <40 y n=9622 | ≥40 y n=9839 | p value | |||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| n | % | n | % | n | % | n | % | ||||
| Thick | 6104 | 4489 | 31.4% | 1615 | 31.4% | 0.931 | 3440 | 35.8% | 2664 | 27.1% | 0.000 |
| Thin | 5401 | 4184 | 29.2% | 1217 | 23.7% | 0.000 | 2268 | 23.6% | 3133 | 31.8% | 0.000 |
| Dry | 7212 | 5562 | 38.8% | 1650 | 32.1% | 0.000 | 3345 | 34.8% | 3867 | 39.3% | 0.000 |
| Oily | 2258 | 1595 | 11.1% | 663 | 12.9% | 0.001 | 1245 | 12.9% | 1013 | 10.3% | 0.000 |
| Damaged | 8266 | 6723 | 47.0% | 1543 | 30.0% | 0.000 | 4234 | 44.0% | 4032 | 41.0% | 0.000 |
| Frizzy due to humidity | 2703 | 2064 | 14.4% | 639 | 12.4% | 0.000 | 1285 | 13.4% | 1418 | 14.4% | 0.000 |
| Difficult to smoothen | 1801 | 1363 | 9.5% | 438 | 8.5% | 0.037 | 918 | 9.5% | 883 | 9.0% | 0.000 |
| Badly defined curls | 1566 | 1168 | 8.2% | 398 | 7.7% | 0.368 | 770 | 8.0% | 796 | 8.1% | 0.000 |
| Too much volume | 2055 | 1539 | 10.7% | 516 | 10.0% | 0.165 | 1087 | 11.3% | 968 | 9.8% | 0.000 |
| Low density | 2066 | 1544 | 10.8% | 522 | 10.2% | 0.222 | 966 | 10.0% | 1100 | 11.2% | 0.000 |
| Split ends | 3272 | 2533 | 17.7% | 739 | 14.4% | 0.000 | 1631 | 17.0% | 1641 | 16.7% | 0.000 |
| Dull without shine | 2028 | 1538 | 10.7% | 490 | 9.5% | 0.016 | 956 | 9.9% | 1072 | 10.9% | 0.000 |
| Hair loss | 10470 | 7964 | 55.6% | 2506 | 48.8% | 0.000 | 5122 | 53.2% | 5348 | 54.4% | 0.000 |
| Bald | 364 | 198 | 1.4% | 166 | 3.2% | 0.000 | 172 | 1.8% | 192 | 2.0% | 0.000 |
| CURL | |||||||||||
| Straight | 6355 | 4285 | 29.9% | 2068 | 40.2% | 0.000 | 3027 | 31.5% | 3328 | 33.8% | 0.000 |
| Wavy | 8092 | 6354 | 44.4% | 1737 | 33.8% | 0.000 | 3992 | 41.5% | 4100 | 41.7% | 0.796 |
| Curly | 2487 | 2042 | 14.3% | 443 | 8.6% | 0.000 | 1269 | 13.2% | 1219 | 12.4% | 0.000 |
| Kinky | 2526 | 1636 | 11.3% | 890 | 17.3% | 0.000 | 1334 | 13.9% | 1192 | 12.1% | 0.000 |
Table 2.
Characteristics of Hair Based on Ethnicity
| n | European n=3480 | African n=3468 | Hispanic n=3009 | Asia n=8457 | Others n=1949 | ||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Population | n | % | n | % | n | % | n | % | n | % | |
| Thick | 6104 | 1135 | 32.6% | 1411 | 40.7% | 1010 | 33.6% | 2219 | 26.2% | 630 | 32.3% |
| Thin | 5401 | 1207 | 34.7% | 867 | 25.0% | 946 | 31.4% | 1968 | 23.3% | 721 | 37.0% |
| Dry | 7212 | 1153 | 33.1% | 1617 | 46.6% | 1077 | 35.8% | 2964 | 35.0% | 723 | 37.1% |
| Oily | 2258 | 333 | 9.6% | 324 | 9.3% | 320 | 10.6% | 1122 | 13.3% | 227 | 11.6% |
| Damaged | 8266 | 1205 | 34.6% | 1181 | 34.1% | 1328 | 44.1% | 4028 | 47.6% | 826 | 42.4% |
| Frizzy due to humidity | 2703 | 847 | 24.3% | 363 | 10.5% | 377 | 12.5% | 934 | 11.0% | 428 | 22.0% |
| Difficult to smoothen | 1801 | 324 | 9.3% | 403 | 11.6% | 248 | 8.2% | 744 | 8.8% | 174 | 8.9% |
| Badly defined curls | 1566 | 390 | 11.2% | 230 | 6.6% | 307 | 10.2% | 526 | 6.2% | 246 | 12.6% |
| Too much volume | 2055 | 400 | 11.5% | 561 | 16.2% | 503 | 16.7% | 388 | 4.6% | 320 | 16.4% |
| Low density | 2066 | 389 | 11.2% | 222 | 6.4% | 185 | 6.1% | 1153 | 13.6% | 208 | 10.7% |
| Split ends | 3272 | 730 | 21.0% | 510 | 14.7% | 560 | 18.6% | 1237 | 14.6% | 449 | 23.0% |
| Dull without shine | 2028 | 455 | 13.1% | 226 | 6.5% | 383 | 12.7% | 801 | 9.5% | 264 | 13.5% |
| Hair loss | 10470 | 1838 | 52.8% | 1387 | 40.0% | 1662 | 55.2% | 5031 | 59.5% | 1014 | 52.0% |
| Bald | 364 | 42 | 1.2% | 112 | 3.2% | 58 | 1.9% | 137 | 1.6% | 30 | 1.5% |
| CURL | |||||||||||
| Straight | 6355 | 1094 | 31.4% | 1143 | 33.0% | 975 | 32.4% | 2835 | 33.5% | 605 | 31.0% |
| Wavy | 8092 | 1493 | 42.9% | 1441 | 41.6% | 1155 | 38.4% | 3588 | 42.4% | 769 | 39.5% |
| Curly | 2488 | 423 | 12.2% | 417 | 12.0% | 419 | 13.9% | 1066 | 12.6% | 293 | 15.0% |
| Kinky | 2526 | 470 | 10.5% | 466 | 10.4% | 460 | 11.5% | 968 | 11.4% | 282 | 14.5% |
Table 3.
Impact on Daily Life of Individuals According to Hair Thickness, Types, Hair Damage State, and Curl Degree
| Stress Level in Personal Life | Tiredness | Lack Sleep | Stress Level in Professional Life | Lack Energy | Lack Confidence | Feel Bad About Myself | Lack Cheerfulness | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| N | % | N | % | N | % | N | % | N | % | N | % | N | % | N | % | |||
| Hair thickness | 19097 | |||||||||||||||||
| Thick | 6104 | 31.96% | 4030 | 66.02% | 3598 | 58.94% | 3199 | 52.41% | 2622 | 42.96% | 1357 | 22.23% | 978 | 16.02% | 899 | 14.73% | 831 | 13.61% |
| Thin | 5401 | 28.28% | 3618 | 66.99% | 3248 | 60.14% | 2885 | 53.42% | 2414 | 44.70% | 1186 | 21.96% | 866 | 16.03% | 792 | 14.66% | 688 | 12.74% |
| 0.273 | 0.1936 | 0.2798 | 0.06045 | 0.72525 | 0.9862 | 0.9228 | 0.166160 | |||||||||||
| Hair type | 9470 | |||||||||||||||||
| Dry | 7212 | 76.16% | 4636 | 64.28% | 4173 | 57.86% | 3720 | 51.58% | 3066 | 42.51% | 1676 | 23.24% | 1253 | 17.37% | 1124 | 15.59% | 1038 | 14.39% |
| Oily | 2258 | 23.84% | 1547 | 68.51% | 1352 | 59.88% | 1222 | 54.12% | 1041 | 46.10% | 543 | 24.05% | 389 | 17.23% | 376 | 16.65% | 330 | 14.61% |
| 0.0002 | 0.090 | 0.0351 | 0.00266 | 0.4284 | 0.8727 | 0.2256 | 0.79340 | |||||||||||
| Hair damage | 19096 | |||||||||||||||||
| Damaged | 8266 | 43.29% | 6156 | 74.47% | 5091 | 61.59% | 4781 | 57.84% | 4133 | 50.00% | 1957 | 23.68% | 1502 | 18.17% | 1344 | 16.26% | 1195 | 14.46% |
| Not damaged | 10830 | 56.71% | 6711 | 61.97% | 6329 | 58.44% | 5676 | 52.41% | 4606 | 42.51% | 2123 | 19.60% | 1483 | 13.69% | 1373 | 12.68% | 1273 | 11.75% |
| <0.0001 | <0.0001 | <0.0001 | <0.0001 | <0.0001 | <0.0001 | <0.0001 | <0.0001 | |||||||||||
| Damaged male | 1541 | 29.99% | 1110 | 72.03% | 917 | 59.51% | 903 | 58.60% | 859 | 55.74% | 340 | 22.06% | 276 | 17.91% | 256 | 16.61% | 265 | 17.20% |
| Damaged female | 6723 | 46.96% | 5046 | 75.06% | 4174 | 62.09% | 3878 | 57.68% | 3274 | 48.70% | 1616 | 24.04% | 1225 | 18.22% | 1087 | 16.17% | 929 | 13.82% |
| 0.0153 | 0.0646 | 0.5300 | 0.0000 | 0.1073 | 0.8037 | 0.6980 | 0.0008 | |||||||||||
| CURL degree | ||||||||||||||||||
| Straight or wavy | 11236 | 58.84% | 7527 | 66.99% | 6486 | 57.73% | 6074 | 54.06% | 4906 | 43.66% | 2196 | 19.54% | 1655 | 14.73% | 1450 | 12.90% | 1323 | 11.77% |
| Curly | 4340 | 22.73% | 2912 | 67.10% | 2865 | 66.01% | 2499 | 57.58% | 2201 | 50.71% | 1088 | 25.07% | 803 | 18.50% | 732 | 16.87% | 641 | 14.77% |
| Kinky | 3521 | 18.44% | 2182 | 61.97% | 1889 | 53.65% | 1700 | 48.28% | 1468 | 41.69% | 727 | 20.65% | 467 | 13.26% | 477 | 13.55% | 457 | 12.98% |
| 19,097 | <0.0001 | <0.0001 | <0.0001 | <0.0001 | <0.0001 | <0.0001 | <0.0001 | <0.0001 | ||||||||||
Note: P-values that are significant are shown in red [P-value <0.05].
A 64.3% of individuals with dry hair had high stress levels in their personal life vs 68.5% of those with oily hair (p<10−3). Moreover “lack of sleep”, and “ stress level in professional life” were significantly higher in oily hair individuals (54.1% vs 51.6%, p=0.03, and 46.1% vs 42.5%, p=0.002). Hair damage state and different curl degrees also had significantly different impact on daily life (Table 3).
Our results show that the highest proportion of damaged hair was in China (44.8%) and Japan (44.6%) and the lowest in France (35.4%). Among those with damaged hair, the highest level of stress in personal life was in Japan (81.1%), stress in professional life in India (68.1%), and impact on sleep in India (66.5%) (Table 4). The highest proportion of dry hair was in Japan (44.8%) and USA (40.5%) and lowest in China (33%). Among those with dry hair, the highest level of stress in personal life was in Japan (84.4%), stress in professional life in India (63.9%), and impact on sleep in India (68.3%). The highest proportion of oily hair was in China (14.3%) and India (13.8%) and lowest in France (7.7%). Among those with oily hair, the highest level of stress in personal life was in Japan (84.4%), stress in professional life in India (63.9%), and impact on sleep in India (68.8%) (Table 4).
Table 4.
Impact on Daily Life per Country in Those with Damaged, Dry, and Oily Hair
| Stress Level in Personal Life | Tiredness | Lack Sleep | Stress Level in Professional Life | Lack Energy | Lack Confidence | Feel Bad About Myself | Lack Cheerfulness | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Hair damage | N | % | N | % | N | % | N | % | N | % | N | % | N | % | N | % | |||
| 19,461 | 8266 | 42.5% | 5431 | 65.7% | 4787 | 57.91% | 4352 | 52.65% | 3640 | 44.04% | 1760 | 21.29% | 1308 | 15.82% | 1170 | 14.15% | 1088 | 13.16% | |
| Brazil | 2073 | 882 | 42.5% | 572 | 64.9% | 615 | 69.73% | 450 | 51.02% | 485 | 54.99% | 272 | 30.84% | 160 | 18.14% | 196 | 22.22% | 140 | 15.87% |
| China | 2603 | 1166 | 44.8% | 808 | 69.3% | 490 | 42.02% | 532 | 45.63% | 356 | 30.53% | 202 | 17.32% | 137 | 11.75% | 150 | 12.86% | 121 | 10.38% |
| France | 1617 | 573 | 35.4% | 420 | 73.3% | 401 | 69.98% | 348 | 60.73% | 135 | 23.56% | 82 | 14.31% | 76 | 13.26% | 57 | 9.95% | 22 | 3.84% |
| India | 2960 | 1302 | 44.0% | 829 | 63.7% | 888 | 68.20% | 866 | 66.51% | 887 | 68.13% | 265 | 20.35% | 251 | 19.28% | 196 | 15.05% | 220 | 16.90% |
| Indonesia | 2255 | 1000 | 44.3% | 445 | 44.5% | 533 | 53.30% | 484 | 48.40% | 323 | 32.30% | 266 | 26.60% | 183 | 18.30% | 137 | 13.70% | 166 | 16.60% |
| Japan | 451 | 208 | 46.1% | 170 | 81.7% | 57 | 27.40% | 77 | 37.02% | 45 | 21.63% | 43 | 20.67% | 78 | 37.50% | 37 | 17.79% | 27 | 12.98% |
| Mexico | 2292 | 1023 | 44.6% | 746 | 72.9% | 967 | 94.53% | 550 | 53.76% | 510 | 49.85% | 147 | 14.37% | 104 | 10.17% | 96 | 9.38% | 85 | 8.31% |
| South Africa | 2698 | 1090 | 40.4% | 711 | 65.2% | 549 | 50.37% | 468 | 42.94% | 404 | 37.06% | 236 | 21.65% | 179 | 16.42% | 169 | 15.50% | 179 | 16.42% |
| USA | 2512 | 1022 | 40.7% | 730 | 71.4% | 618 | 60.47% | 577 | 56.46% | 495 | 48.43% | 247 | 24.17% | 140 | 13.70% | 132 | 12.92% | 128 | 12.52% |
| Stress Level in Personal Life | Tiredness | Lack Sleep | Stress Level in Professional Life | Lack Energy | Lack Confidence | Feel Bad About Myself | Lack Cheerfulness | ||||||||||||
| Hair type | N | % | N | % | N | % | N | % | N | % | N | % | N | % | N | % | |||
| Dry | 19461 | 7212 | 37.1% | 4774 | 66.2% | 4175 | 57.89% | 3836 | 53.19% | 3175 | 44.02% | 1518 | 21.05% | 1119 | 15.52% | 987 | 13.69% | 918 | 12.73% |
| Brazil | 2073 | 717 | 34.6% | 454 | 63.3% | 499 | 69.60% | 354 | 49.37% | 397 | 55.37% | 228 | 31.80% | 124 | 17.29% | 143 | 19.94% | 113 | 15.76% |
| China | 2603 | 860 | 33.0% | 577 | 67.1% | 353 | 41.05% | 389 | 45.23% | 265 | 30.81% | 156 | 18.14% | 121 | 14.07% | 114 | 13.26% | 102 | 11.86% |
| France | 1617 | 564 | 34.9% | 428 | 75.9% | 407 | 72.16% | 343 | 60.82% | 133 | 23.58% | 72 | 12.77% | 81 | 14.36% | 62 | 10.99% | 23 | 4.08% |
| India | 2960 | 1033 | 34.9% | 666 | 64.5% | 712 | 68.93% | 706 | 68.34% | 707 | 68.44% | 205 | 19.85% | 184 | 17.81% | 153 | 14.81% | 166 | 16.07% |
| Indonesia | 2255 | 833 | 36.9% | 397 | 47.7% | 428 | 51.38% | 410 | 49.22% | 262 | 31.45% | 216 | 25.93% | 155 | 18.61% | 117 | 14.05% | 133 | 15.97% |
| Japan | 451 | 202 | 44.8% | 169 | 83.7% | 63 | 31.19% | 74 | 36.63% | 50 | 24.75% | 48 | 23.76% | 76 | 37.62% | 41 | 20.30% | 33 | 16.34% |
| Mexico | 2292 | 903 | 39.4% | 645 | 71.4% | 859 | 95.13% | 493 | 54.60% | 464 | 51.38% | 129 | 14.29% | 85 | 9.41% | 88 | 9.75% | 73 | 8.08% |
| South Africa | 2698 | 1083 | 40.1% | 713 | 65.8% | 541 | 49.95% | 502 | 46.35% | 405 | 37.40% | 236 | 21.79% | 166 | 15.33% | 153 | 14.13% | 162 | 14.96% |
| USA | 2512 | 1017 | 40.5% | 725 | 71.3% | 618 | 60.77% | 565 | 55.56% | 492 | 48.38% | 228 | 22.42% | 127 | 12.49% | 116 | 11.41% | 113 | 11.11% |
| Stress Level in Personal Life | Tiredness | Lack Sleep | Stress Level in Professional Life | Lack Energy | Lack Confidence | Feel Bad About Myself | Lack Cheerfulness | ||||||||||||
| Hair type | N | % | N | % | N | % | N | % | N | % | N | % | N | % | N | % | |||
| Oily | 19461 | 2258 | 11.6% | 1495 | 66.2% | 1327 | 58.77% | 1226 | 54.30% | 1043 | 46.19% | 459 | 20.33% | 350 | 15.50% | 320 | 14.17% | 292 | 12.93% |
| Brazil | 2073 | 227 | 11.0% | 150 | 66.1% | 162 | 71.37% | 124 | 54.63% | 132 | 58.15% | 60 | 26.43% | 36 | 15.86% | 47 | 20.70% | 34 | 14.98% |
| China | 2603 | 373 | 14.3% | 269 | 72.1% | 169 | 45.31% | 177 | 47.45% | 120 | 32.17% | 65 | 17.43% | 43 | 11.53% | 40 | 10.72% | 37 | 9.92% |
| France | 1617 | 125 | 7.7% | 97 | 77.6% | 92 | 73.60% | 76 | 60.80% | 30 | 24.00% | 14 | 11.20% | 14 | 11.20% | 14 | 11.20% | 3 | 2.40% |
| India | 2960 | 407 | 13.8% | 248 | 60.9% | 288 | 70.76% | 277 | 68.06% | 260 | 63.88% | 82 | 20.15% | 83 | 20.39% | 67 | 16.46% | 74 | 18.18% |
| Indonesia | 2255 | 283 | 12.5% | 133 | 47.0% | 164 | 57.95% | 140 | 49.47% | 115 | 40.64% | 65 | 22.97% | 49 | 17.31% | 35 | 12.37% | 41 | 14.49% |
| Japan | 451 | 45 | 10.0% | 38 | 84.4% | 12 | 26.67% | 18 | 40.00% | 10 | 22.22% | 12 | 26.67% | 21 | 46.67% | 11 | 24.44% | 8 | 17.78% |
| Mexico | 2292 | 264 | 11.5% | 197 | 74.6% | 254 | 96.21% | 144 | 54.55% | 141 | 53.41% | 37 | 14.02% | 28 | 10.61% | 34 | 12.88% | 21 | 7.95% |
| South Africa | 2698 | 281 | 10.4% | 186 | 66.2% | 130 | 46.26% | 126 | 44.84% | 98 | 34.88% | 61 | 21.71% | 42 | 14.95% | 40 | 14.23% | 41 | 14.59% |
| USA | 2512 | 253 | 10.1% | 177 | 70.0% | 144 | 56.92% | 144 | 56.92% | 137 | 54.15% | 63 | 24.90% | 34 | 13.44% | 32 | 12.65% | 33 | 13.04% |
Note: In red, the cumulative values for the 9 countries involved in the project.
The highest prevalence of straight or wavy hair was in China (86.6%) and Japan (84.3%). Among those with straight or wavy hair, the highest stress levels in personal life was in Japan (81.3%) and the lowest in Indonesia (45.5%) and Brazil (58.6%). The highest impact on sleep was in India (68.2%) and France (60%) and the lowest in Japan (37.4%). The highest stress level in professional life was in India (68.4%) and the lowest in Japan (23.4%) and France (22.6%). The highest prevalence of curly hair was in Brazil (42.6%) and lowest in China (5.5%). Among those with curly hair, the highest stress level in personal life was in France, stress in professional life in India (64.2%), and impact on sleep in France (68.5%). The highest prevalence of kinky hair was in South Africa (59.4%) and lowest in Japan (0.9%) (Table 5).
Table 5.
Impact on Daily Life per Country According to the Degree of Curl
| 1 | 5 | 5 | 5 | 1 | 1 | 1 | 1 | ||||||||||||
| Stress Level in Personal Life | Tiredness | Lack Sleep | Stress Level in Professional Life | Lack Energy | Lack Confidence | Feel Bad About Myself | Lack Cheerfulness | ||||||||||||
| CURL degree | N | % | N | % | N | % | N | % | N | % | N | % | N | % | N | % | |||
| Straight or wavy | 19461 | 11,236 | 57.7% | 7527 | 67.0% | 6486 | 57.73% | 6074 | 54.06% | 4906 | 43.66% | 2196 | 19.54% | 1655 | 14.73% | 1450 | 12.90% | 1323 | 11.77% |
| Brazil | 2073 | 476 | 23.0% | 279 | 58.6% | 323 | 67.86% | 234 | 49.16% | 278 | 58.40% | 135 | 28.36% | 82 | 17.23% | 100 | 21.01% | 74 | 15.55% |
| China | 2603 | 2255 | 86.6% | 1580 | 70.1% | 960 | 42.57% | 1021 | 45.28% | 716 | 31.75% | 390 | 17.29% | 261 | 11.57% | 279 | 12.37% | 229 | 10.16% |
| France | 1617 | 1142 | 70.6% | 859 | 75.2% | 817 | 71.54% | 685 | 59.98% | 258 | 22.59% | 151 | 13.22% | 156 | 13.66% | 126 | 11.03% | 38 | 3.33% |
| India | 2960 | 2108 | 71.2% | 1341 | 63.6% | 1429 | 67.79% | 1437 | 68.17% | 1442 | 68.41% | 358 | 16.98% | 307 | 14.56% | 246 | 11.67% | 299 | 14.18% |
| Indonesia | 2255 | 1620 | 71.8% | 737 | 45.5% | 822 | 50.74% | 772 | 47.65% | 523 | 32.28% | 391 | 24.14% | 256 | 15.80% | 195 | 12.04% | 235 | 14.51% |
| Japan | 451 | 380 | 84.3% | 309 | 81.3% | 121 | 31.84% | 142 | 37.37% | 89 | 23.42% | 98 | 25.79% | 148 | 38.95% | 75 | 19.74% | 64 | 16.84% |
| Mexico | 2292 | 1435 | 62.6% | 1060 | 73.9% | 1426 | 99.37% | 789 | 54.98% | 756 | 52.68% | 199 | 13.87% | 147 | 10.24% | 141 | 9.83% | 108 | 7.53% |
| South Africa | 2698 | 749 | 27.8% | 559 | 74.6% | 436 | 58.21% | 400 | 53.40% | 323 | 43.12% | 236 | 31.51% | 166 | 22.16% | 161 | 21.50% | 163 | 21.76% |
| USA | 2512 | 1071 | 42.6% | 803 | 75.0% | 657 | 61.34% | 594 | 55.46% | 521 | 48.65% | 238 | 22.22% | 132 | 12.32% | 127 | 11.86% | 113 | 10.55% |
| 19,461 | 11,236 | 7527 | 617.8% | 6991 | 55127 | 6074 | 47146 | 4906 | 38131 | 2196 | 19339 | 1655 | 15651 | 1450 | 13104 | 1323 | 1144 | ||
| Stress Level in Personal Life | Tiredness | Lack Sleep | Stress Level in Professional Life | Lack Energy | Lack Confidence | Feel Bad About Myself | Lack Cheerfulness | ||||||||||||
| CURL degree | N | % | N | % | N | % | N | % | N | % | N | % | N | % | N | % | |||
| Curly | 19461 | 4340 | 22.3% | 2912 | 67.1% | 2865 | 66.01% | 2499 | 57.58% | 2201 | 50.71% | 1088 | 25.07% | 803 | 18.50% | 732 | 16.87% | 641 | 14.77% |
| Brazil | 2073 | 884 | 42.6% | 609 | 68.9% | 645 | 72.96% | 494 | 55.88% | 524 | 59.28% | 308 | 34.84% | 163 | 18.44% | 187 | 21.15% | 152 | 17.19% |
| China | 2603 | 142 | 5.5% | 101 | 71.1% | 77 | 54.23% | 70 | 49.30% | 51 | 35.92% | 28 | 19.72% | 25 | 17.61% | 24 | 16.90% | 25 | 17.61% |
| France | 1617 | 346 | 21.4% | 285 | 82.4% | 278 | 80.35% | 237 | 68.50% | 118 | 34.10% | 47 | 13.58% | 56 | 16.18% | 47 | 13.58% | 15 | 4.34% |
| India | 2960 | 806 | 27.2% | 472 | 58.6% | 591 | 73.33% | 548 | 67.99% | 518 | 64.27% | 213 | 26.43% | 225 | 27.92% | 183 | 22.70% | 183 | 22.70% |
| Indonesia | 2255 | 583 | 25.9% | 281 | 48.2% | 330 | 56.60% | 292 | 50.09% | 203 | 34.82% | 167 | 28.64% | 131 | 22.47% | 92 | 15.78% | 99 | 16.98% |
| Japan | 451 | 45 | 10.0% | 37 | 82.2% | 11 | 24.44% | 16 | 35.56% | 8 | 17.78% | 9 | 20.00% | 17 | 37.78% | 9 | 20.00% | 6 | 13.33% |
| Mexico | 2292 | 596 | 26.0% | 448 | 75.2% | 564 | 94.63% | 327 | 54.87% | 309 | 51.85% | 84 | 14.09% | 61 | 10.23% | 67 | 11.24% | 47 | 7.89% |
| South Africa | 2698 | 283 | 10.5% | 200 | 70.7% | 154 | 54.42% | 147 | 51.94% | 124 | 43.82% | 86 | 30.39% | 57 | 20.14% | 58 | 20.49% | 53 | 18.73% |
| USA | 2512 | 655 | 26.1% | 479 | 73.1% | 414 | 63.21% | 368 | 56.18% | 346 | 52.82% | 146 | 22.29% | 68 | 10.38% | 65 | 9.92% | 61 | 9.31% |
| Stress Level in Personal Life | Tiredness | Lack Sleep | Stress Level in Professional Life | Lack Energy | Lack Confidence | Feel Bad About Myself | Lack Cheerfulness | ||||||||||||
| CURL degree | N | % | N | % | N | % | N | % | N | % | N | % | N | % | N | % | |||
| Kinly | 19461 | 3521 | 18.1% | 2181 | 61.9% | 1888 | 53.62% | 1700 | 48.28% | 1467 | 41.66% | 727 | 20.65% | 467 | 13.26% | 477 | 13.55% | 457 | 12.98% |
| Brazil | 2073 | 707 | 34.1% | 426 | 60.3% | 491 | 69.45% | 378 | 53.47% | 395 | 55.87% | 229 | 32.39% | 132 | 18.67% | 152 | 21.50% | 122 | 17.26% |
| China | 2603 | 135 | 5.2% | 80 | 59.3% | 44 | 32.59% | 61 | 45.19% | 42 | 31.11% | 24 | 17.78% | 18 | 13.33% | 18 | 13.33% | 16 | 11.85% |
| France | 1617 | 120 | 7.4% | 86 | 71.7% | 80 | 66.67% | 81 | 67.50% | 34 | 28.33% | 16 | 13.33% | 12 | 10.00% | 12 | 10.00% | 8 | 6.67% |
| India | 2960 | 28 | 0.9% | 12 | 42.9% | 20 | 71.43% | 21 | 75.00% | 23 | 82.14% | 8 | 28.57% | 7 | 25.00% | 6 | 21.43% | 5 | 17.86% |
| Indonesia | 2255 | 31 | 1.4% | 15 | 48.4% | 23 | 74.19% | 22 | 70.97% | 12 | 38.71% | 13 | 41.94% | 7 | 22.58% | 8 | 25.81% | 9 | 29.03% |
| Japan | 451 | 4 | 0.9% | 4 | 100.0% | 2 | 50.00% | 2 | 50.00% | 0 | 0.00% | 1 | 25.00% | 1 | 25.00% | 0 | 0.00% | 0 | 0.00% |
| Mexico | 2292 | 221 | 9.6% | 152 | 68.8% | 168 | 76.02% | 101 | 45.70% | 99 | 44.80% | 31 | 14.03% | 26 | 11.76% | 26 | 11.76% | 19 | 8.60% |
| South Africa | 2698 | 1602 | 59.4% | 982 | 61.3% | 734 | 45.82% | 652 | 40.70% | 532 | 33.21% | 240 | 14.98% | 179 | 11.17% | 172 | 10.74% | 181 | 11.30% |
| USA | 2512 | 673 | 26.8% | 425 | 63.2% | 381 | 56.61% | 382 | 56.76% | 331 | 49.18% | 165 | 24.52% | 85 | 12.63% | 83 | 12.33% | 97 | 14.41% |
Notes: In red, the cumulative values for the 9 countries involved in the project.
Discussion
This is the first multinational study that assessed hair type and characteristics and impact on daily life. Even subtle manipulations of a person’s hair can alter people’s perception of his age, attractiveness, and health.9 Most dermatological literature on hair has focused on effect of hair loss on people’s daily lives, yet none has assessed the impact of hair types on quality of life. Hair that is healthy, strong, and shiny signals overall physical health. Conversely, hair that is dry, damaged, and thin is perceived to be unhealthy and related to an illness, which makes the person less attractive.9 Since people tend to be seduced by healthy, young, and attractive individuals, well-groomed and good-looking hair may signal these parameters.9,10 However, our study showed that around a quarter of males and a third of females reported thin hair, and a significant difference as noted in those aged ≥40 y.o compared to those <40 y.o. Moreover, around a third of males and 40% of females reported dry hair, with a significantly higher proportion in those ages 40 and above. With regard to damaged hair, it is reported in around half of females and a third of males, with surprisingly, a higher proportion in those below the age of 40 compared to those aged 40 and above. A significantly higher proportion of females reported their hair being “frizzy due to humidity”, “dull without shine”, “with split ends”, or “difficult to smoothen”. Difference between males and females was noted regarding hair having “badly defined curls”, “too much volume”, and “low density”. The proportion of curly hair in females was significantly higher than in males. Kinky hair was significantly more frequent in males and in those <40 y.o.
Thick hair was more frequent in African followed by Hispanic, European, and finally Asian ethnicity. On the contrary, thin hair was more frequent in European (over a third of individuals) followed by Hispanic, African, and lastly Asian ethnicity. Dry hair was significantly higher in African ethnicity followed by Hispanic, Asian, and lastly European ethnicity. Asian hair is known for exhibiting the strongest mechanical properties and is known for its straightness, and large diameter which is attributed to the cuticle layer being thicker than that in Caucasians with more compact cuticle cells.11,12 Surprisingly, the highest proportion of damaged hair was noted in Asian followed by Hispanic, European, and lastly African ethnicity.
Straight hair was most frequent in Asian ethnicity, wavy hair in European and Asian ethnicity, curly hair in Hispanic and Asian ethnicity, while kinky hair was most frequent in Hispanic ethnicity.
Impact on daily life in patients with alopecia areata and androgenetic alopecia has been studied quite extensively13–20 and reflects the impairment that hair problems can have, which is a greater impairment than that of other common dermatoses like acne vulgaris. Androgenetic alopecia is also associated with impairment in emotions, which is greater than in the function and symptom dimensions.13 However, comparably, very little is known on the effect of hair types on an individual’s personal well-being. Our study showed that individuals with damaged hair tend to be significantly more tired, have higher stress levels on personal and professional lives and lack of sleep. Moreover, they tend to be less energetic, confident, cheerful, feel less good about themselves. No significant difference was noted between those who have thick vs thin hair regarding stress levels, lack of sleep, tiredness, work–life balance, confidence, cheerfulness, and feeling good about themselves. However, those with oily hair tend to be more stressed and those with dry hair tend to have less work–life balance. Damaged hair in males and females had a different impact on daily life. Males with damaged hair were more likely to have stress in their professional life and to lack cheerfulness. On the contrary, females with damaged hair were more likely to have stress in their personal life.
Hair types and characteristics on daily life differed significantly among countries. Moreover, their impact on daily life also differed among countries. This might highly be attributed to differences in perception of beauty among cultures.
Our results show that the highest proportion of damaged hair was in China and the lowest in France. The highest proportion of dry hair was in Japan and lowest in China. The highest proportion of oily hair was in China and lowest in France. The highest prevalence of straight or wavy hair was in China. The highest prevalence of curly hair was in Brazil and lowest in China. The impact of curl degree on daily life differed between countries. Among those with straight or wavy hair, the highest stress level in personal life was in Japan and the lowest in Indonesia and Brazil. In fact, in Brazil, curly hair is celebrated and considered a symbol of beauty. This is probably due to the country’s culture and diverse population. It would be interesting to conduct future studies aiming to assess the exact relation between societal pressure and impact of curl degree and damage status on daily life. Despite the presence of a growing appreciation for curly hair in recent years in many countries, curly hair had significant impact on daily lives of individuals. Among those with curly hair, the highest stress level in personal life was in France, stress in professional life in India, and impact on sleep in France. Having more manageable hair that remains straight and capable of defying humidity has been a long-time desire among women across different ethnic groups. This is evident in the multitude of straightening techniques used across the globe.
Conclusion
Our research shows that, while hair problems vary by age, gender, and ethnicity, they remain widespread. Given that hair is a prominent feature of physical appearance, our findings highlight the significant impact that hair type has on an individual’s daily life. Hair plays a crucial role in shaping self-image and identity, and understanding how hair characteristics affect both men and women’s daily experiences is essential. Our study demonstrates how individuals perceive themselves and how they are perceived by others, emphasizing the importance of hair in personal and social contexts. This insight can inform interventions aimed at enhancing body image and self-esteem. Additionally, our research contributes to a deeper understanding of the comprehensive impact of hair on people’s lives, which can lead to improvements in healthcare, social attitudes, and product development.
Acknowledgments
The authors acknowledge the technical support of Aurelie Abric, Cecilia Trehin and Thierry Lageat.
Funding Statement
This project was funded by L’Oréal Research and Innovation.
Data Sharing Statement
The data that support the findings of this study are available from the corresponding author upon reasonable request.
Ethical Considerations
The research was approved by L’Oréal Research and Innovation, the national ID-RCB number is 2023-A02701-44.
Disclosure
Frederic Flament; Aurelie Maudet; Philippe Barbarat; Meriem Jabnoun; Muriel Bayer-Vanmoen; Audrey Imbert Legrain; Stéphanie Leclerc Mercier & Laurence Lebarbanchon are employees of L’Oréal. Charles Taieb and Charbel Skayem are sub-contracted to help in data analysis and writing. Stephanie Leclerc-Mercier reports being an employee of Vichy, during the conduct of the study. The authors report no other conflicts of interest in this work.
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Associated Data
This section collects any data citations, data availability statements, or supplementary materials included in this article.
Data Availability Statement
The data that support the findings of this study are available from the corresponding author upon reasonable request.