International Journal of Cosmetic Science, 2015, 37, 92–97
doi: 10.1111/ics.12174
A study on seasonal variation of skin parameters in Korean males E. J. Song*, J. A. Lee*, J. J. Park*, H. J. Kim*, N. S. Kim*, K. S. Byun*, G. S. Choi† and T. K. Moon* *Ellead Co., Ltd., 325, Hwangsaeul-ro, Bundang-gu Seongnam-si Gyeonggi-do 463-824, Korea and †Department of Dermatology, Inha University College of Medicine, Incheon, South Korea
Received 08 July 2014, Accepted 11 October 2014
Keywords: clinical evaluation, environment, korean men, skin physiological parameters
Synopsis OBJECTIVE: The physiological characteristics of the skin are varied greatly, depending on gender, age, region and race, and many dermatologic researches have been performed through various research methods. This study aimed to examine how Korean men’s skin conditions were influenced by temperature or humidity changes caused by seasonal rotations. METHODS: A total of 100 healthy Korean men, age range 20–59 years, participated in the study for both summer and winter. We compared on the characteristics of skin between summer and winter. The skin hydration, skin pH and TEWL were evaluated on the forehead, cheek and forearm. The skin sebum content of the glabella, nasal ala and cheek was measured using Sebumeterâ (SM810, Courage+Khazaka, Germany). Cutometerâ (MPA 580 Courage+Khazaka, Germany) the elasticity was measured by on the cheeks, and PRIMOS liteâ (Phase shift Rapid in vivo Measurement of Skin, GFMesstechnik GmbH, Germany) was used to evaluate wrinkles on crow’s feet. Lastly, in addition, the skin pore of the face was measured using the Janusâ (PSI, Korea) which is a facial analysis system. RESULTS: The results were as follows: the comparison of hydration in summer and winter shows significant differences in their forehead, cheeks and forearm. The pH values of the skin surface were generally higher in winter, and significantly different on each site, and the sebum content was higher in summer than in winter. As a result of the pore measurement, the summer showed more pores compared to the winter, and there was a statistically significant difference in skin pores between summer and winter. The sensitivity measured by stinging test increases significantly more in winter than in summer. However, there were no seasonal differences in wrinkles and skin brightness. CONCLUSION: The skin surface pH, TEWL, sebum content, hydration, elasticity, wrinkles, skin pore and skin sensitivity vary with seasons and body regions in Korean men. sume Re OBJECTIF: Les caracteristiques physiologiques de la peau varient considerablement, selon le sexe, l’^ age, la region et la race, et de nombreuses recherches dermatologiques ont ete effectuees par di examiner comverses methodes de recherche. Cette etude vise a ment la peau des hommes coreens a ete influencee par les changements de temperature ou d’humidite causees par les changements de saison. Correspondence: E. J. Song, Ellead Ltd., 325, Hwangsaeul-ro, Bundang-gu, Seongnam-si, Gyeonggi-do 463-824, Korea. Tel.: +82 31 709 9070; fax: +82 31 703 9071; e-mail: [email protected]
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METHODES: 100 hommes coreens sains, de la tranche d’^ age 20 l’etude pour l’ete et l’hiver. Nous avons 59 ans, ont participe a compare les caracteristiques de la peau entre l’ete et l’hiver. L’hydratation de la peau, pH de la peau, et PIE ont ete evalues sur le front, les joues, et l’avant-bras. Le contenu de sebum de la peau de l’aide du Sebumela glabelle, aile nasale, et joue ont ete mesures a terâ (SM810, Courage + Khazaka, Allemagne); l’elasticite a ete mesuree par Cutometerâ (MPA 580 Courage + Khazaka, Allemagne) sur les joues, et le PRIMOS liteâ (Phase shift Rapid In vivo Measurement Of Skin, GFMesstechnik GmbH, Allemagne) a ete utilise pour evaluer les rides sur les pattes d’oie. Enfin, en outre, les pores de la peau du visage ont ete mesurees en utilisant la Janusâ (PSI, Coree), qui est un systeme d’analyse du visage. RESULTATS: Les resultats sont les suivants: La comparaison d’hydratation en ete et en hiver montre des differences significatives dans leur front, les joues, et l’avant-bras. Les valeurs de pH de la surface de la peau sont generalement plus elevees en hiver, et significativement differentes sur chaque site, et le taux de sebum est plus eleve en ete qu’en hiver. En tant que resultat de la mesure des pores, l’ete montre plus de pores par rapport a l’hiver, et il y avait une difference statistiquement significative dans les pores de la peau entre l’ete et l’hiver. La sensibilite mesuree par un test “stinging” augmente de facßon significative en hiver par rapport a l’ete. Cependant, il n’y avait pas de differences saisonnieres dans les rides et la luminosite de la peau. CONCLUSION: Le pH de la surface de la peau, la PIE, le taux de sebum, l’hydratation, l’elasticite, les rides, les pores de la peau, et la sensibilite de la peau varient en fonction des saisons et des regions de corps chez les hommes coreennes. Introduction Researches on skin characteristics for various races and nations can be conducted by measuring the surface of skin through noninvasive methods. South Korea is a country with clear distinctions of four seasons and is geographically located in 37°240 N latitude and 127°70 E longitude. There was the mean temperature of the months containing the maximum temperature/humidity (summer) and of the minimum temperature/humidity (winter) from 1981 to 2010. (Table I). Skin is the outer covering of the body and plays a role in protecting the body from physical and chemical factors and in preventing the loss of moisture. Generally, it shows wide differences according to subjects’ residential environment, parts of the body, gender, age, race and skincare such as the use of cosmetics including sunscreen. And numerous researches have been conducted to
© 2014 Society of Cosmetic Scientists and the Societe Francßaise de Cosmetologie
E. J. Song et al.
Seasonal skin variability Table I Climate and latitude information of Korea
Country (city)
Latitude
Longitude
Korea, (Seongnam)
37°240 N
127°70 E
Average monthly temperature and humidity of the month with the highest temperature
Average monthly temperature and humidity of the month with the lowest temperature
24.9°C 74.2%
2.4°C 59.7%
Korea meteorological administration (1981–2010).
find out the characteristics of skin [1, 2]. However, there have been very few researches on the characteristics of men’s skin around the world. In this context, this study was conducted on changes in skin of Korean men according to different seasons and measured the following items. Regarding the hydration of stratum corneum, there are several methods of measuring the capacitance and conductance of skin, and transepidermal water loss (TEWL) evaporated through the skin is used as an indicator of a healthy functioning skin barrier in the stratum corneum [3]. First, skin moisturization is closely connected with the water content of the stratum corneum, the outermost layer of the epidermis; the measurement of the water content of the stratum corneum plays a key role in finding out whether skin surface is normal and healthy or has pathological characteristics [4]. In the current experiment, the water content of skin surface was measured by measuring capacitance, which increases as resistance decreases. When the stratum corneum in skin loses its water by such factors, the skin is likely to become rougher or drier. Some seasonal factors also affect the normal skin and may cause severe skin diseases [5]. According to Marrakchi et al.’s research, the elder one becomes, hydration declines with ageing and this is due to the reduction in natural moisturizing factors found in the stratum corneum [6]. Second, the characteristics of skin can be identified by measuring the amount of sebum on the skin surface. The amount of sebum depends on the amount of lipid secreted from skin surface, and this maintains skin homeostasis and serves as the permeability barrier [7]. In addition, the degree of sebum generation is an important factor for the evaluation of skin condition, for sebum contains the natural moisturizing factor that prevents skin dryness, skin ageing and controls water retention. The amount of sebum varies greatly among individuals, and using a sebum absorbing tape is the most frequently used method for evaluating the amount of sebum on skin. Third, the degree of the distribution of skin pores on skin and the degree of skin brightness may show differences according to seasons. Moreover, they are included in the measurement items of this study and they can be influenced by the use of sunscreen and exposure to external environment. Fourth, the acidity and alkalinity of skin can be measured by using the skin pH meter. The nearer the skin surface is to neutrality or alkalinity, the weaker it may become to the invasion of germs. This suggests that the acid mantle of skin surface plays a defensive role against external invasion [8]. Fifth, skin elasticity is a marker of skin ageing and can be measured by applying certain pressure on skin and observing the degree of restoration. Sixth, another factor that is closely associated with ageing other than skin elasticity is the presence of wrinkles which shows distinct differences according to external environment and age [9]. It is also closely related to the amount of lipids and moisture on skin surface. Seventh, as for
sensitivity evaluation, in which the degree of skin stimulation is determined by a subject’s individual opinion can be used. As reported by Akutsu et al.’s research [10], the characteristics of Japanese teenagers’ and adults’ facial skin surface were investigated according to their age and seasonal changes, and the results indicate that both the teenagers and adults skin showed lower hydration and higher TEWL in winter than in summer. Meanwhile, De Paepe et al.’s research observed that transepidermal water loss of nasolabial skin increases more in winter than in fall [11]; however, skin pH or hydration does not indicate distinctive difference by seasons. As written above, various researches have studied skin changes by seasons, and there exists difference by their study methods such as race, age and area measured. This study aims to examine how Korean men’s skin conditions are influenced by the temperature or humidity changes resulted from seasonal changes. Materials and methods Subjects The study was conducted with Korean men participants living in Seoul and Gyeonggi-do and working indoors for over 5 years (no outdoor workers), having consistent income and using basic skincare products. They were chosen, excluding persons with an allergy to cosmetics and pharmaceuticals, those with a chronic wasting disease such as hypertension and diabetes, those with a skin disease, and those who had a dermatological surgery in the past 6 months. A total of 100 healthy Korean men, age range 20–59 years, participated in the study for both summer and winter. The subjects were divided by age into four groups (20–29, 30–39, 40–49, 50– 59; 25 male in each group). All subjects acclimated in the controlled rooms at the temperature of 20 24°C and the relative humidity of 40–60% for at least 30 min after washing the face using a typical foam face cleanser. The study was approved by the institutional review board and was conducted in July 2012 and January 2013. Measurements Differences in the skin characteristics of Korean males between summer and winter were investigated between the ages of 20 and 59, using non-invasive methods. The skin hydration, skin pH and transepidermal water loss, of the forehead, cheek and forearm were evaluated using Corneometerâ (CM 825; Courage+Khazaka, Germany), Skin pH-meterâ (PH 900 Courage+Khazaka, Germany) and Tewameterâ (TM 300, Courage+Khazaka, Germany), respectively. The skin sebum content of the glabella, the nasal ala and cheek
© 2014 Society of Cosmetic Scientists and the Societe Francßaise de Cosmetologie International Journal of Cosmetic Science, 37, 92–97
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E. J. Song et al.
Seasonal skin variability Table II Comparison of skin parameters between summer and winter in male
Factors
Hydration (A.U.)
Sebum content (jug m2) Transepidermal water loss (g m2 h) pH
Elasticity (A.U.)
Wrinkle (ji m1) Stinging test (Score) Skin brightness (A.U.) Pore (A.U.)
Site
Forehead Cheek Forearm Ala of nose Glabella Forehead Cheek Forearm Forehead Cheek Forearm R2 R5 R7 Crow’s feet Nasolabial Face Face
Summer
62.55 57.48 46.98 81.46 55.54 21.41 22.80 10.16 5.15 5.39 5.03 0.61 0.49 0.29 20.17 0.99 54.48 63.19
13.89 10.17 7.64 61.34 30.73 4.99 5.02 2.88 0.38 0.35 0.35 0.08 0.08 0.05 4.13 1.05 3.33 7.62
Winter
51.70 49.55 39.23 46.42 33.46 17.40 21.64 8.24 5.53 5.82 5.44 0.58 0.44 0.26 20.44 1.99 55.15 61.02
11.65* 10.84* 7.21* 28.59* 15.78* 4.67* 6.12 2.50* 0.43* 0.29* 0.53* 0.08* 0.06* 0.04* 3.31 1.70* 2.94 7.63*
Statistical analysis is performed by independent t-test. Results are shown as the mean SD (*Significant differences between summer and winter, P < 0.05).
was measured using Sebumeterâ (SM810, Courage+Khazaka, Germany). Cutometerâ (MPA580, Courage+Khazaka, Germany) was used to measure the elasticity of the cheeks. A probe with a diameter of 2 mm was mounted on this equipment for the test. On-time 2.0 s and Off-time 2.0 s were then applied to the specified negative pressure of the mode 1 condition (450 mbar). PRIMOS liteâ (GFMesstechnik GmbH, Germany) was used to evaluate the wrin-
kles on crow’s feet. Using the optical 3D skin measurement system PRIMOS lite, image capturing process on crow’s feet was performed. The skin pore and brightness of the face was measured using Janusâ (PSI, Korea) which is a facial analysis system. Janusâ is a 10 megapixel ultra-high resolution camera. Facial images were taken with Janus and analysed with the image analysis program within Janus. All subjects responded to self-assessment questionnaires composed of questions about symptoms and signs of sensitive skin. In the lactic acid sting test, the sting sensation was rated. Statistical analysis All results were expressed as mean standard deviation (SD), and data were calculated with SPSS (PASW Statistics 18, IBM). Statistical analyses were performed using the independent t-test (if two groups) in which P values < 0.05 were considered significant, and the Pearson correlation analysis. Results The comparison of hydration in summer and winter shows significant difference in their forehead, cheeks and forearm areas, and hydration was decreased in winter as compared to that in summer. In summer, the forehead showed the highest value when compared with other test regions. The means of skin hydration were as follows: forehead 62.55 13.89, cheek 57.48 10.17, forearm 46.98 7.64 for summer, and forehead 51.70 11.65, cheek 49.55 10.84, forearm 39.23 7.21 for winter, respectively. The pH values of the skin surface were generally higher in winter and significantly different at each site. The means of the pH were as follows: forehead 5.15 0.38, cheek 5.39 0.35, forearm 5.03 0.35 for summer, and forehead 5.53 0.43, cheek
(a)
(b)
(c)
(d)
Figure 1 Seasonal change in (a) skin hydration, (b) TEWL, (c) pH, and (d) elasticity in Korean men. Results are shown as the mean SD (*Significant differences between summer and winter, P < 0.05).
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© 2014 Society of Cosmetic Scientists and the Societe Francßaise de Cosmetologie International Journal of Cosmetic Science, 37, 92–97
E. J. Song et al.
Seasonal skin variability
(a)
(b)
(c)
(d)
(e)
Figure 2 Seasonal change in (a) sebum content, (b) pore, (c) sensitivity, and (d) wrinkle (e) Skin brightness in Korean men. Statistical analysis is performed by independent t-test. Results are shown as the mean SD (*Significant differences between summer and winter, P < 0.05.).
Figure 3 Correlation between hydration and sensitivity in Korean men.
Figure 4 Correlation between hydration and TEWL in Korean men.
5.82 0.29, forearm 5.44 0.53 for winter. The TEWL values of the difference between summer and winter were much higher on the forehead than on the forearm. The means of TEWL were as follows: forehead 21.41 4.99, cheek 22.80 5.02, forearm 10.16 2.88 for summer, and forehead 17.40 4.67, cheek
21.6.4 6.12, forearm 8.24 2.50 for winter. The TEWL of forehead and forearm tended to increase in summer compared to those in winter. The results of skin elasticity were as follows: R2 0.61 0.08, R5 0.49 0.08, R7 0.29 0.05 for summer, and R2 0.58 0.08, R5 0.44 0.06, R7 0.26 0.04 for winter.
© 2014 Society of Cosmetic Scientists and the Societe Francßaise de Cosmetologie International Journal of Cosmetic Science, 37, 92–97
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International Journal of Cosmetic Science, 2015, 37, 92–97
doi: 10.1111/ics.12174
A study on seasonal variation of skin parameters in Korean males E. J. Song*, J. A. Lee*, J. J. Park*, H. J. Kim*, N. S. Kim*, K. S. Byun*, G. S. Choi† and T. K. Moon* *Ellead Co., Ltd., 325, Hwangsaeul-ro, Bundang-gu Seongnam-si Gyeonggi-do 463-824, Korea and †Department of Dermatology, Inha University College of Medicine, Incheon, South Korea
Received 08 July 2014, Accepted 11 October 2014
Keywords: clinical evaluation, environment, korean men, skin physiological parameters
Synopsis OBJECTIVE: The physiological characteristics of the skin are varied greatly, depending on gender, age, region and race, and many dermatologic researches have been performed through various research methods. This study aimed to examine how Korean men’s skin conditions were influenced by temperature or humidity changes caused by seasonal rotations. METHODS: A total of 100 healthy Korean men, age range 20–59 years, participated in the study for both summer and winter. We compared on the characteristics of skin between summer and winter. The skin hydration, skin pH and TEWL were evaluated on the forehead, cheek and forearm. The skin sebum content of the glabella, nasal ala and cheek was measured using Sebumeterâ (SM810, Courage+Khazaka, Germany). Cutometerâ (MPA 580 Courage+Khazaka, Germany) the elasticity was measured by on the cheeks, and PRIMOS liteâ (Phase shift Rapid in vivo Measurement of Skin, GFMesstechnik GmbH, Germany) was used to evaluate wrinkles on crow’s feet. Lastly, in addition, the skin pore of the face was measured using the Janusâ (PSI, Korea) which is a facial analysis system. RESULTS: The results were as follows: the comparison of hydration in summer and winter shows significant differences in their forehead, cheeks and forearm. The pH values of the skin surface were generally higher in winter, and significantly different on each site, and the sebum content was higher in summer than in winter. As a result of the pore measurement, the summer showed more pores compared to the winter, and there was a statistically significant difference in skin pores between summer and winter. The sensitivity measured by stinging test increases significantly more in winter than in summer. However, there were no seasonal differences in wrinkles and skin brightness. CONCLUSION: The skin surface pH, TEWL, sebum content, hydration, elasticity, wrinkles, skin pore and skin sensitivity vary with seasons and body regions in Korean men. sume Re OBJECTIF: Les caracteristiques physiologiques de la peau varient considerablement, selon le sexe, l’^ age, la region et la race, et de nombreuses recherches dermatologiques ont ete effectuees par di examiner comverses methodes de recherche. Cette etude vise a ment la peau des hommes coreens a ete influencee par les changements de temperature ou d’humidite causees par les changements de saison. Correspondence: E. J. Song, Ellead Ltd., 325, Hwangsaeul-ro, Bundang-gu, Seongnam-si, Gyeonggi-do 463-824, Korea. Tel.: +82 31 709 9070; fax: +82 31 703 9071; e-mail: [email protected]
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METHODES: 100 hommes coreens sains, de la tranche d’^ age 20 l’etude pour l’ete et l’hiver. Nous avons 59 ans, ont participe a compare les caracteristiques de la peau entre l’ete et l’hiver. L’hydratation de la peau, pH de la peau, et PIE ont ete evalues sur le front, les joues, et l’avant-bras. Le contenu de sebum de la peau de l’aide du Sebumela glabelle, aile nasale, et joue ont ete mesures a terâ (SM810, Courage + Khazaka, Allemagne); l’elasticite a ete mesuree par Cutometerâ (MPA 580 Courage + Khazaka, Allemagne) sur les joues, et le PRIMOS liteâ (Phase shift Rapid In vivo Measurement Of Skin, GFMesstechnik GmbH, Allemagne) a ete utilise pour evaluer les rides sur les pattes d’oie. Enfin, en outre, les pores de la peau du visage ont ete mesurees en utilisant la Janusâ (PSI, Coree), qui est un systeme d’analyse du visage. RESULTATS: Les resultats sont les suivants: La comparaison d’hydratation en ete et en hiver montre des differences significatives dans leur front, les joues, et l’avant-bras. Les valeurs de pH de la surface de la peau sont generalement plus elevees en hiver, et significativement differentes sur chaque site, et le taux de sebum est plus eleve en ete qu’en hiver. En tant que resultat de la mesure des pores, l’ete montre plus de pores par rapport a l’hiver, et il y avait une difference statistiquement significative dans les pores de la peau entre l’ete et l’hiver. La sensibilite mesuree par un test “stinging” augmente de facßon significative en hiver par rapport a l’ete. Cependant, il n’y avait pas de differences saisonnieres dans les rides et la luminosite de la peau. CONCLUSION: Le pH de la surface de la peau, la PIE, le taux de sebum, l’hydratation, l’elasticite, les rides, les pores de la peau, et la sensibilite de la peau varient en fonction des saisons et des regions de corps chez les hommes coreennes. Introduction Researches on skin characteristics for various races and nations can be conducted by measuring the surface of skin through noninvasive methods. South Korea is a country with clear distinctions of four seasons and is geographically located in 37°240 N latitude and 127°70 E longitude. There was the mean temperature of the months containing the maximum temperature/humidity (summer) and of the minimum temperature/humidity (winter) from 1981 to 2010. (Table I). Skin is the outer covering of the body and plays a role in protecting the body from physical and chemical factors and in preventing the loss of moisture. Generally, it shows wide differences according to subjects’ residential environment, parts of the body, gender, age, race and skincare such as the use of cosmetics including sunscreen. And numerous researches have been conducted to
© 2014 Society of Cosmetic Scientists and the Societe Francßaise de Cosmetologie
E. J. Song et al.
Seasonal skin variability
Figure 8 Correlation between skin wrinkle and skin elasticity parameters of the cutometer in Korean men.
study demonstrated the pore is the factor affected by seasons, and it is thought that when exposed to hot and humid environment, pores are affected more. It is believed that skin pores are greater as the secretion of sebum increases. There was more secretion of sebum in summer than in winter. In addition, the results showed that the sizes of skin pores were statistically and significantly larger than those in winter; therefore, it is suggested that the skin pores are closely related with the amount of sebum secretion. As a result of a comparison between the pore and elasticity R2 and R7, there was a negative correlation. Also, according to B. Y. Kim et al., the pore tended to get larger as the subjects had acne and lower elasticity (R7), and it was reported that there was a negative correlation between the pore and elasticity R7 value [17]. It was found that the more the sebum was secreted, the wider the pore became and the skin sagged, decreasing the elasticity. There was no seasonal difference in wrinkles. It was generally expected that the brightness of skin would get darker in summer than in winter due to more exposure to UV, but our research showed that there was no difference in the brightness of skin. It is thought that the brightness of skin is affected by gender, age, the exposure to UV and especially the use of cosmetic products (UV protectors).
As a result of an investigation of the impacts of seasonal changes on sensitivity, it tended to increase significantly in winter compared to summer. It has been reported that the sensitivity may be affected by many factors such as the type of cosmetics and habits of use as well as environmental factors such as wind and temperature, etc. [18]. Considering that, to the same extent, it is a measurement by subjective assessment, there may be differences of expression among different ethnicities or genders that may affect the results of the sensitivity. The skin conditions may be affected by intrinsic factors such as sex and age as well as external factors such as temperature and humidity. Especially, it was found that there were meaningful results from the differences in the contrasting temperatures between the hot summer and the cold winter in South Korea. In conclusion, the factors that can maintain homogeneity of the skin barriers may noticeably change by seasons. Acknowledgements This study was sponsored by Ministry of Health & Welfare and Foundation of Korea Cosmetic Industry Institute.
References 1. Elias, P.M. The skin barrier as an innate immune element. Semin. Immunopathol. 29, 3–14 (2007). 2. Denda, M., Nakatani, M., Ikeyama, K., Tsutsumi, M. and Denda, S. Epidermal keratinocytes as the forefront of the sensory system. Exp. Dermatol. 16, 157–161 (2007). 3. Rawlings, A.V. and Matts, P.J. Stratum corneum moisturization at the molecular level: an update in relation to the dry skin cycle. J. Invest Dermatol. 124, 1099–1110 (2005). 4. Choi, E.H. and Park, H.Y. Skin barrier in aged skin. Kor. Soc. Skin Barrier Res. 12, 79–84 (2010). 5. Serup Jorgen, J., Jemec, G.B.E. and Grove, G.L. Handbook of Non-Invasive Methods and the Skin. CRC Press Inc., 33–35 (2006). 6. Marrakchi, S. and Maibach, H.I. Biophysical parameters of skin: map of human face, regional, and age-related differences. Contact Derm. 57, 28–34 (2007). 7. Elsner, P., Berardesca, E. and Maibach, H.I., eds. Bioengineering of the Skin: Water and the Stratum Corneum. CRC Press Boca Raton, 23–24 (1994).
8. Schmid-Wendtner, M.H. and Korting, H.C. The pH of the skin surface and its impact on the barrier function. Skin Pharmacol. Physiol. 19, 296–302 (2006). 9. Barel, A.O. and Clarys, P.. Measurement of epidermal capacitance. In: Handbook of NonInvasive Methods and the Skin (Serup Jorgen, J., Jemec, G.B.E. and Grove, G.L.). CRC Press Inc., 317–328 (1995). 10. Akutsu, N., Ooguri, M., Onoddera, T. et al. Functional characteristics of the skin surface of children approaching puberty: age and seasonal influences. Acta Derm. Venereol., 89, 21–27 (2009). 11. De paepe, K., Houben, E., Adam, R., Hachem, J.P., Roseeuw, D. and Rogiers, V. Seasonal effects on the nasolabial skin condition. Skin Pharmacol. Physiol. 22, 8–14 (2009). 12. Qiu, H., Long, X., Ye, J.C. et al. Influence of season on some skin Properties: winter vs. summer, as experienced by 354 Shanghaiese women of various ages. Int. J. Cosmet. Sci. 33, 377–383 (2011). 13. Rogers, J., Harding, C., Mayo, A., Banks, J. and Rawlings, A. Stratum corneum lipids:
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the effect of ageing and the seasons. Arch. Dermatol. 288, 765–770 (1996). Denda, M., Sato, J., Masuda, Y. et al. Exposure to a dry environment enhances epidermal permeability barrier function. J. Invest. Dermatol. 111, 858–863 (1998). Loden, M., Buraczewska, I. and Edlund, F. The irritation potential and reservoir effect of mild soaps. Contact Derm. 49, 91–96 (2003). Kim, E., Kim, S., Nam, G.W., Lee, H., Moon, S. and Chang, I. The alkaline pH-adapted skin barrier is disrupted severely by SLSinduced irritation. Int. J. Cosmet. Sci. 31, 263–269 (2009). Kim, B.Y., Choi, J.W., Park, K.C. and Youn, S.W. Sebum, acne, skin elasticity, and gender difference- which is the major influencing factor for facial pores? Skin Res. Technol. 19, 45–53 (2013). Cheng, Y., Dong, Y.Y., Dong, M.X. et al. Protection effect of cosmetics on human skin under simulated rigorous environment. Skin Res. Technol. 14, 45–52 (2008).
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doi: 10.1111/ics.12174
A study on seasonal variation of skin parameters in Korean males E. J. Song*, J. A. Lee*, J. J. Park*, H. J. Kim*, N. S. Kim*, K. S. Byun*, G. S. Choi† and T. K. Moon* *Ellead Co., Ltd., 325, Hwangsaeul-ro, Bundang-gu Seongnam-si Gyeonggi-do 463-824, Korea and †Department of Dermatology, Inha University College of Medicine, Incheon, South Korea
Received 08 July 2014, Accepted 11 October 2014
Keywords: clinical evaluation, environment, korean men, skin physiological parameters
Synopsis OBJECTIVE: The physiological characteristics of the skin are varied greatly, depending on gender, age, region and race, and many dermatologic researches have been performed through various research methods. This study aimed to examine how Korean men’s skin conditions were influenced by temperature or humidity changes caused by seasonal rotations. METHODS: A total of 100 healthy Korean men, age range 20–59 years, participated in the study for both summer and winter. We compared on the characteristics of skin between summer and winter. The skin hydration, skin pH and TEWL were evaluated on the forehead, cheek and forearm. The skin sebum content of the glabella, nasal ala and cheek was measured using Sebumeterâ (SM810, Courage+Khazaka, Germany). Cutometerâ (MPA 580 Courage+Khazaka, Germany) the elasticity was measured by on the cheeks, and PRIMOS liteâ (Phase shift Rapid in vivo Measurement of Skin, GFMesstechnik GmbH, Germany) was used to evaluate wrinkles on crow’s feet. Lastly, in addition, the skin pore of the face was measured using the Janusâ (PSI, Korea) which is a facial analysis system. RESULTS: The results were as follows: the comparison of hydration in summer and winter shows significant differences in their forehead, cheeks and forearm. The pH values of the skin surface were generally higher in winter, and significantly different on each site, and the sebum content was higher in summer than in winter. As a result of the pore measurement, the summer showed more pores compared to the winter, and there was a statistically significant difference in skin pores between summer and winter. The sensitivity measured by stinging test increases significantly more in winter than in summer. However, there were no seasonal differences in wrinkles and skin brightness. CONCLUSION: The skin surface pH, TEWL, sebum content, hydration, elasticity, wrinkles, skin pore and skin sensitivity vary with seasons and body regions in Korean men. sume Re OBJECTIF: Les caracteristiques physiologiques de la peau varient considerablement, selon le sexe, l’^ age, la region et la race, et de nombreuses recherches dermatologiques ont ete effectuees par di examiner comverses methodes de recherche. Cette etude vise a ment la peau des hommes coreens a ete influencee par les changements de temperature ou d’humidite causees par les changements de saison. Correspondence: E. J. Song, Ellead Ltd., 325, Hwangsaeul-ro, Bundang-gu, Seongnam-si, Gyeonggi-do 463-824, Korea. Tel.: +82 31 709 9070; fax: +82 31 703 9071; e-mail: [email protected]
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METHODES: 100 hommes coreens sains, de la tranche d’^ age 20 l’etude pour l’ete et l’hiver. Nous avons 59 ans, ont participe a compare les caracteristiques de la peau entre l’ete et l’hiver. L’hydratation de la peau, pH de la peau, et PIE ont ete evalues sur le front, les joues, et l’avant-bras. Le contenu de sebum de la peau de l’aide du Sebumela glabelle, aile nasale, et joue ont ete mesures a terâ (SM810, Courage + Khazaka, Allemagne); l’elasticite a ete mesuree par Cutometerâ (MPA 580 Courage + Khazaka, Allemagne) sur les joues, et le PRIMOS liteâ (Phase shift Rapid In vivo Measurement Of Skin, GFMesstechnik GmbH, Allemagne) a ete utilise pour evaluer les rides sur les pattes d’oie. Enfin, en outre, les pores de la peau du visage ont ete mesurees en utilisant la Janusâ (PSI, Coree), qui est un systeme d’analyse du visage. RESULTATS: Les resultats sont les suivants: La comparaison d’hydratation en ete et en hiver montre des differences significatives dans leur front, les joues, et l’avant-bras. Les valeurs de pH de la surface de la peau sont generalement plus elevees en hiver, et significativement differentes sur chaque site, et le taux de sebum est plus eleve en ete qu’en hiver. En tant que resultat de la mesure des pores, l’ete montre plus de pores par rapport a l’hiver, et il y avait une difference statistiquement significative dans les pores de la peau entre l’ete et l’hiver. La sensibilite mesuree par un test “stinging” augmente de facßon significative en hiver par rapport a l’ete. Cependant, il n’y avait pas de differences saisonnieres dans les rides et la luminosite de la peau. CONCLUSION: Le pH de la surface de la peau, la PIE, le taux de sebum, l’hydratation, l’elasticite, les rides, les pores de la peau, et la sensibilite de la peau varient en fonction des saisons et des regions de corps chez les hommes coreennes. Introduction Researches on skin characteristics for various races and nations can be conducted by measuring the surface of skin through noninvasive methods. South Korea is a country with clear distinctions of four seasons and is geographically located in 37°240 N latitude and 127°70 E longitude. There was the mean temperature of the months containing the maximum temperature/humidity (summer) and of the minimum temperature/humidity (winter) from 1981 to 2010. (Table I). Skin is the outer covering of the body and plays a role in protecting the body from physical and chemical factors and in preventing the loss of moisture. Generally, it shows wide differences according to subjects’ residential environment, parts of the body, gender, age, race and skincare such as the use of cosmetics including sunscreen. And numerous researches have been conducted to
© 2014 Society of Cosmetic Scientists and the Societe Francßaise de Cosmetologie
E. J. Song et al.
Seasonal skin variability Table I Climate and latitude information of Korea
Country (city)
Latitude
Longitude
Korea, (Seongnam)
37°240 N
127°70 E
Average monthly temperature and humidity of the month with the highest temperature
Average monthly temperature and humidity of the month with the lowest temperature
24.9°C 74.2%
2.4°C 59.7%
Korea meteorological administration (1981–2010).
find out the characteristics of skin [1, 2]. However, there have been very few researches on the characteristics of men’s skin around the world. In this context, this study was conducted on changes in skin of Korean men according to different seasons and measured the following items. Regarding the hydration of stratum corneum, there are several methods of measuring the capacitance and conductance of skin, and transepidermal water loss (TEWL) evaporated through the skin is used as an indicator of a healthy functioning skin barrier in the stratum corneum [3]. First, skin moisturization is closely connected with the water content of the stratum corneum, the outermost layer of the epidermis; the measurement of the water content of the stratum corneum plays a key role in finding out whether skin surface is normal and healthy or has pathological characteristics [4]. In the current experiment, the water content of skin surface was measured by measuring capacitance, which increases as resistance decreases. When the stratum corneum in skin loses its water by such factors, the skin is likely to become rougher or drier. Some seasonal factors also affect the normal skin and may cause severe skin diseases [5]. According to Marrakchi et al.’s research, the elder one becomes, hydration declines with ageing and this is due to the reduction in natural moisturizing factors found in the stratum corneum [6]. Second, the characteristics of skin can be identified by measuring the amount of sebum on the skin surface. The amount of sebum depends on the amount of lipid secreted from skin surface, and this maintains skin homeostasis and serves as the permeability barrier [7]. In addition, the degree of sebum generation is an important factor for the evaluation of skin condition, for sebum contains the natural moisturizing factor that prevents skin dryness, skin ageing and controls water retention. The amount of sebum varies greatly among individuals, and using a sebum absorbing tape is the most frequently used method for evaluating the amount of sebum on skin. Third, the degree of the distribution of skin pores on skin and the degree of skin brightness may show differences according to seasons. Moreover, they are included in the measurement items of this study and they can be influenced by the use of sunscreen and exposure to external environment. Fourth, the acidity and alkalinity of skin can be measured by using the skin pH meter. The nearer the skin surface is to neutrality or alkalinity, the weaker it may become to the invasion of germs. This suggests that the acid mantle of skin surface plays a defensive role against external invasion [8]. Fifth, skin elasticity is a marker of skin ageing and can be measured by applying certain pressure on skin and observing the degree of restoration. Sixth, another factor that is closely associated with ageing other than skin elasticity is the presence of wrinkles which shows distinct differences according to external environment and age [9]. It is also closely related to the amount of lipids and moisture on skin surface. Seventh, as for
sensitivity evaluation, in which the degree of skin stimulation is determined by a subject’s individual opinion can be used. As reported by Akutsu et al.’s research [10], the characteristics of Japanese teenagers’ and adults’ facial skin surface were investigated according to their age and seasonal changes, and the results indicate that both the teenagers and adults skin showed lower hydration and higher TEWL in winter than in summer. Meanwhile, De Paepe et al.’s research observed that transepidermal water loss of nasolabial skin increases more in winter than in fall [11]; however, skin pH or hydration does not indicate distinctive difference by seasons. As written above, various researches have studied skin changes by seasons, and there exists difference by their study methods such as race, age and area measured. This study aims to examine how Korean men’s skin conditions are influenced by the temperature or humidity changes resulted from seasonal changes. Materials and methods Subjects The study was conducted with Korean men participants living in Seoul and Gyeonggi-do and working indoors for over 5 years (no outdoor workers), having consistent income and using basic skincare products. They were chosen, excluding persons with an allergy to cosmetics and pharmaceuticals, those with a chronic wasting disease such as hypertension and diabetes, those with a skin disease, and those who had a dermatological surgery in the past 6 months. A total of 100 healthy Korean men, age range 20–59 years, participated in the study for both summer and winter. The subjects were divided by age into four groups (20–29, 30–39, 40–49, 50– 59; 25 male in each group). All subjects acclimated in the controlled rooms at the temperature of 20 24°C and the relative humidity of 40–60% for at least 30 min after washing the face using a typical foam face cleanser. The study was approved by the institutional review board and was conducted in July 2012 and January 2013. Measurements Differences in the skin characteristics of Korean males between summer and winter were investigated between the ages of 20 and 59, using non-invasive methods. The skin hydration, skin pH and transepidermal water loss, of the forehead, cheek and forearm were evaluated using Corneometerâ (CM 825; Courage+Khazaka, Germany), Skin pH-meterâ (PH 900 Courage+Khazaka, Germany) and Tewameterâ (TM 300, Courage+Khazaka, Germany), respectively. The skin sebum content of the glabella, the nasal ala and cheek
© 2014 Society of Cosmetic Scientists and the Societe Francßaise de Cosmetologie International Journal of Cosmetic Science, 37, 92–97
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E. J. Song et al.
Seasonal skin variability Table II Comparison of skin parameters between summer and winter in male
Factors
Hydration (A.U.)
Sebum content (jug m2) Transepidermal water loss (g m2 h) pH
Elasticity (A.U.)
Wrinkle (ji m1) Stinging test (Score) Skin brightness (A.U.) Pore (A.U.)
Site
Forehead Cheek Forearm Ala of nose Glabella Forehead Cheek Forearm Forehead Cheek Forearm R2 R5 R7 Crow’s feet Nasolabial Face Face
Summer
62.55 57.48 46.98 81.46 55.54 21.41 22.80 10.16 5.15 5.39 5.03 0.61 0.49 0.29 20.17 0.99 54.48 63.19
13.89 10.17 7.64 61.34 30.73 4.99 5.02 2.88 0.38 0.35 0.35 0.08 0.08 0.05 4.13 1.05 3.33 7.62
Winter
51.70 49.55 39.23 46.42 33.46 17.40 21.64 8.24 5.53 5.82 5.44 0.58 0.44 0.26 20.44 1.99 55.15 61.02
11.65* 10.84* 7.21* 28.59* 15.78* 4.67* 6.12 2.50* 0.43* 0.29* 0.53* 0.08* 0.06* 0.04* 3.31 1.70* 2.94 7.63*
Statistical analysis is performed by independent t-test. Results are shown as the mean SD (*Significant differences between summer and winter, P < 0.05).
was measured using Sebumeterâ (SM810, Courage+Khazaka, Germany). Cutometerâ (MPA580, Courage+Khazaka, Germany) was used to measure the elasticity of the cheeks. A probe with a diameter of 2 mm was mounted on this equipment for the test. On-time 2.0 s and Off-time 2.0 s were then applied to the specified negative pressure of the mode 1 condition (450 mbar). PRIMOS liteâ (GFMesstechnik GmbH, Germany) was used to evaluate the wrin-
kles on crow’s feet. Using the optical 3D skin measurement system PRIMOS lite, image capturing process on crow’s feet was performed. The skin pore and brightness of the face was measured using Janusâ (PSI, Korea) which is a facial analysis system. Janusâ is a 10 megapixel ultra-high resolution camera. Facial images were taken with Janus and analysed with the image analysis program within Janus. All subjects responded to self-assessment questionnaires composed of questions about symptoms and signs of sensitive skin. In the lactic acid sting test, the sting sensation was rated. Statistical analysis All results were expressed as mean standard deviation (SD), and data were calculated with SPSS (PASW Statistics 18, IBM). Statistical analyses were performed using the independent t-test (if two groups) in which P values < 0.05 were considered significant, and the Pearson correlation analysis. Results The comparison of hydration in summer and winter shows significant difference in their forehead, cheeks and forearm areas, and hydration was decreased in winter as compared to that in summer. In summer, the forehead showed the highest value when compared with other test regions. The means of skin hydration were as follows: forehead 62.55 13.89, cheek 57.48 10.17, forearm 46.98 7.64 for summer, and forehead 51.70 11.65, cheek 49.55 10.84, forearm 39.23 7.21 for winter, respectively. The pH values of the skin surface were generally higher in winter and significantly different at each site. The means of the pH were as follows: forehead 5.15 0.38, cheek 5.39 0.35, forearm 5.03 0.35 for summer, and forehead 5.53 0.43, cheek
(a)
(b)
(c)
(d)
Figure 1 Seasonal change in (a) skin hydration, (b) TEWL, (c) pH, and (d) elasticity in Korean men. Results are shown as the mean SD (*Significant differences between summer and winter, P < 0.05).
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© 2014 Society of Cosmetic Scientists and the Societe Francßaise de Cosmetologie International Journal of Cosmetic Science, 37, 92–97
E. J. Song et al.
Seasonal skin variability
(a)
(b)
(c)
(d)
(e)
Figure 2 Seasonal change in (a) sebum content, (b) pore, (c) sensitivity, and (d) wrinkle (e) Skin brightness in Korean men. Statistical analysis is performed by independent t-test. Results are shown as the mean SD (*Significant differences between summer and winter, P < 0.05.).
Figure 3 Correlation between hydration and sensitivity in Korean men.
Figure 4 Correlation between hydration and TEWL in Korean men.
5.82 0.29, forearm 5.44 0.53 for winter. The TEWL values of the difference between summer and winter were much higher on the forehead than on the forearm. The means of TEWL were as follows: forehead 21.41 4.99, cheek 22.80 5.02, forearm 10.16 2.88 for summer, and forehead 17.40 4.67, cheek
21.6.4 6.12, forearm 8.24 2.50 for winter. The TEWL of forehead and forearm tended to increase in summer compared to those in winter. The results of skin elasticity were as follows: R2 0.61 0.08, R5 0.49 0.08, R7 0.29 0.05 for summer, and R2 0.58 0.08, R5 0.44 0.06, R7 0.26 0.04 for winter.
© 2014 Society of Cosmetic Scientists and the Societe Francßaise de Cosmetologie International Journal of Cosmetic Science, 37, 92–97
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International Journal of Cosmetic Science, 2015, 37, 92–97
doi: 10.1111/ics.12174
A study on seasonal variation of skin parameters in Korean males E. J. Song*, J. A. Lee*, J. J. Park*, H. J. Kim*, N. S. Kim*, K. S. Byun*, G. S. Choi† and T. K. Moon* *Ellead Co., Ltd., 325, Hwangsaeul-ro, Bundang-gu Seongnam-si Gyeonggi-do 463-824, Korea and †Department of Dermatology, Inha University College of Medicine, Incheon, South Korea
Received 08 July 2014, Accepted 11 October 2014
Keywords: clinical evaluation, environment, korean men, skin physiological parameters
Synopsis OBJECTIVE: The physiological characteristics of the skin are varied greatly, depending on gender, age, region and race, and many dermatologic researches have been performed through various research methods. This study aimed to examine how Korean men’s skin conditions were influenced by temperature or humidity changes caused by seasonal rotations. METHODS: A total of 100 healthy Korean men, age range 20–59 years, participated in the study for both summer and winter. We compared on the characteristics of skin between summer and winter. The skin hydration, skin pH and TEWL were evaluated on the forehead, cheek and forearm. The skin sebum content of the glabella, nasal ala and cheek was measured using Sebumeterâ (SM810, Courage+Khazaka, Germany). Cutometerâ (MPA 580 Courage+Khazaka, Germany) the elasticity was measured by on the cheeks, and PRIMOS liteâ (Phase shift Rapid in vivo Measurement of Skin, GFMesstechnik GmbH, Germany) was used to evaluate wrinkles on crow’s feet. Lastly, in addition, the skin pore of the face was measured using the Janusâ (PSI, Korea) which is a facial analysis system. RESULTS: The results were as follows: the comparison of hydration in summer and winter shows significant differences in their forehead, cheeks and forearm. The pH values of the skin surface were generally higher in winter, and significantly different on each site, and the sebum content was higher in summer than in winter. As a result of the pore measurement, the summer showed more pores compared to the winter, and there was a statistically significant difference in skin pores between summer and winter. The sensitivity measured by stinging test increases significantly more in winter than in summer. However, there were no seasonal differences in wrinkles and skin brightness. CONCLUSION: The skin surface pH, TEWL, sebum content, hydration, elasticity, wrinkles, skin pore and skin sensitivity vary with seasons and body regions in Korean men. sume Re OBJECTIF: Les caracteristiques physiologiques de la peau varient considerablement, selon le sexe, l’^ age, la region et la race, et de nombreuses recherches dermatologiques ont ete effectuees par di examiner comverses methodes de recherche. Cette etude vise a ment la peau des hommes coreens a ete influencee par les changements de temperature ou d’humidite causees par les changements de saison. Correspondence: E. J. Song, Ellead Ltd., 325, Hwangsaeul-ro, Bundang-gu, Seongnam-si, Gyeonggi-do 463-824, Korea. Tel.: +82 31 709 9070; fax: +82 31 703 9071; e-mail: [email protected]
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METHODES: 100 hommes coreens sains, de la tranche d’^ age 20 l’etude pour l’ete et l’hiver. Nous avons 59 ans, ont participe a compare les caracteristiques de la peau entre l’ete et l’hiver. L’hydratation de la peau, pH de la peau, et PIE ont ete evalues sur le front, les joues, et l’avant-bras. Le contenu de sebum de la peau de l’aide du Sebumela glabelle, aile nasale, et joue ont ete mesures a terâ (SM810, Courage + Khazaka, Allemagne); l’elasticite a ete mesuree par Cutometerâ (MPA 580 Courage + Khazaka, Allemagne) sur les joues, et le PRIMOS liteâ (Phase shift Rapid In vivo Measurement Of Skin, GFMesstechnik GmbH, Allemagne) a ete utilise pour evaluer les rides sur les pattes d’oie. Enfin, en outre, les pores de la peau du visage ont ete mesurees en utilisant la Janusâ (PSI, Coree), qui est un systeme d’analyse du visage. RESULTATS: Les resultats sont les suivants: La comparaison d’hydratation en ete et en hiver montre des differences significatives dans leur front, les joues, et l’avant-bras. Les valeurs de pH de la surface de la peau sont generalement plus elevees en hiver, et significativement differentes sur chaque site, et le taux de sebum est plus eleve en ete qu’en hiver. En tant que resultat de la mesure des pores, l’ete montre plus de pores par rapport a l’hiver, et il y avait une difference statistiquement significative dans les pores de la peau entre l’ete et l’hiver. La sensibilite mesuree par un test “stinging” augmente de facßon significative en hiver par rapport a l’ete. Cependant, il n’y avait pas de differences saisonnieres dans les rides et la luminosite de la peau. CONCLUSION: Le pH de la surface de la peau, la PIE, le taux de sebum, l’hydratation, l’elasticite, les rides, les pores de la peau, et la sensibilite de la peau varient en fonction des saisons et des regions de corps chez les hommes coreennes. Introduction Researches on skin characteristics for various races and nations can be conducted by measuring the surface of skin through noninvasive methods. South Korea is a country with clear distinctions of four seasons and is geographically located in 37°240 N latitude and 127°70 E longitude. There was the mean temperature of the months containing the maximum temperature/humidity (summer) and of the minimum temperature/humidity (winter) from 1981 to 2010. (Table I). Skin is the outer covering of the body and plays a role in protecting the body from physical and chemical factors and in preventing the loss of moisture. Generally, it shows wide differences according to subjects’ residential environment, parts of the body, gender, age, race and skincare such as the use of cosmetics including sunscreen. And numerous researches have been conducted to
© 2014 Society of Cosmetic Scientists and the Societe Francßaise de Cosmetologie
E. J. Song et al.
Seasonal skin variability
Figure 8 Correlation between skin wrinkle and skin elasticity parameters of the cutometer in Korean men.
study demonstrated the pore is the factor affected by seasons, and it is thought that when exposed to hot and humid environment, pores are affected more. It is believed that skin pores are greater as the secretion of sebum increases. There was more secretion of sebum in summer than in winter. In addition, the results showed that the sizes of skin pores were statistically and significantly larger than those in winter; therefore, it is suggested that the skin pores are closely related with the amount of sebum secretion. As a result of a comparison between the pore and elasticity R2 and R7, there was a negative correlation. Also, according to B. Y. Kim et al., the pore tended to get larger as the subjects had acne and lower elasticity (R7), and it was reported that there was a negative correlation between the pore and elasticity R7 value [17]. It was found that the more the sebum was secreted, the wider the pore became and the skin sagged, decreasing the elasticity. There was no seasonal difference in wrinkles. It was generally expected that the brightness of skin would get darker in summer than in winter due to more exposure to UV, but our research showed that there was no difference in the brightness of skin. It is thought that the brightness of skin is affected by gender, age, the exposure to UV and especially the use of cosmetic products (UV protectors).
As a result of an investigation of the impacts of seasonal changes on sensitivity, it tended to increase significantly in winter compared to summer. It has been reported that the sensitivity may be affected by many factors such as the type of cosmetics and habits of use as well as environmental factors such as wind and temperature, etc. [18]. Considering that, to the same extent, it is a measurement by subjective assessment, there may be differences of expression among different ethnicities or genders that may affect the results of the sensitivity. The skin conditions may be affected by intrinsic factors such as sex and age as well as external factors such as temperature and humidity. Especially, it was found that there were meaningful results from the differences in the contrasting temperatures between the hot summer and the cold winter in South Korea. In conclusion, the factors that can maintain homogeneity of the skin barriers may noticeably change by seasons. Acknowledgements This study was sponsored by Ministry of Health & Welfare and Foundation of Korea Cosmetic Industry Institute.
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