Learn about the different types of skin

Several criteria are used to classify  different types of skin. For example, the Fitzpatrick classification, first described in 1975, is based on skin color and its response to sun exposure. It is used to determine the appropriate sun protection factor or to predict the risk of skin cancer, among other applications.  From a cosmetic point of view, skin is classified according to several factors related to its balance: sebaceous secretion, hydration and sensitivity level. Therefore, each type of skin has its own characteristics and requires different care.Skin type is determined by genetics, although it iis also influenced by other factors and may change over time.

Based on these characteristics, there are five types of healthy skin: normal, dry, oily, combination (both oily and dry skin), and sensitive. Below, we describe the main characteristics of each type of skin type.

Normal Skin

This type of skin is neither too dry nor too oily. It has a regular texture, no imperfections, and a clean, soft appearance, and does not require special care.
 

Sensitive Skin

Sensitive skin is more prone to react to stimuli to which normal skin does not react. It is fragile  andusually accompanied by feelings of discomfort, such as heat, tightness, redness or itching. This type of skin loses its barrier ( protective) function, making it easier for microorganisms and irritant substances to penetrate, and increasing the risk of infection and allergic reactions. It is  delicate skin that requires additional care to manage dryness, roughness and its usual appearance. Sometimes, it is referred to as irritated skin instead of sensitive skin; however  these terms are synonymous and there are no dermatological differences between them.

Dry Skin

In many cases, dry skin is caused by external factors such as weather conditionslow air humidity, and immersion in hot water, and it is usually temporary. However, for some people, it may occur more frequently or even be a lifelong condition. Because  dry skin can crack, leaving it more exposed to bacteria, although in general this is not serious,  it may cause other skin disorders, such as eczema, or increase susceptibility to infections if not properly managed.

Dry skin signs and symptoms may vary depending on different factors such as age, health status or  he underlying cause. It is generally characterized by a feeling of tightness and roughness. The skin may also develop an ashy gray appereance, with  desquamation, itching, redness and small cracks. In very dry skin, these cracks may become deeper and,  in more severe cases, may bleed.

Atopic skin is a skin disease characterized by dry skin that leads to desquamation and irritation and causes uncomfortable symptoms, such as itching. The main cause is genetic predisposition, although other factors may trigger  or aggravate the condition, including environmental, allergic,dietary and  clothing related factors.

Oily Skin

Oily skin has a porous, moist and shiny appearance. It is caused by excessive sebum production by the sebaceous glands, and is usually determined by genetic and/or hormonal factors. It is common in adolescents and young adults under 30 years of age and is often associated  with acne.

Combination Skin

Combination skin  presents characteristics of both dry and oily skin ,as the distribution of sebaceous and sweat glands is not homogeneous. Oilness is usually more pronounced in the T- zone (forehead, nose, and chin), while the cheeks are normal or dry.

Scaly Skin

Repeated skin irritation caused by environmental factors, such as sun exposure,  wind, dryness or excessive humidity may cause skin desquamation, that is, the detachment of large scales from the epidermis, which may resemble fine dust. However, desquamation may also  result from certain conditions, such as  allergic reactions,  fungal or staphylococcus infections,  immune system disorders,cancer,or oncological treatments. In these cases,  it is usually accompanied by itching.

Red Spots

There  are many dermatological causes  for the appearance of red spots or rashes, including infections, heat, allergens, immune system disorders, and medications.

Skin Moles

Moles are dark spots on the skin that usually appear during childhood and adolescence. They are caused by clusters of pigmented cells. In general, they are harmless; howeverit is advisable to consult a a dermatologist if they change in size, shape or colour, or if itching or bleeding occurs, as some moles may become cancerous.

In general, it is important to pay attention to skin appearance because, regardless of skin type, certain changes may be signs of a skin problem.

References

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2. Gupta, V., Sharma, V.K. Skin typing: Fitzpatrick grading and others. Clin Dermatol. 2019 Sep;37(5):430–6.

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4. Mayo Clinic. Moisturizers: Options for softer skin [Internet]. 2019 Oct 18. Available at: https://www.mayoclinic.org/diseases-conditions/dry-skin/in-depth/moisturizers/art-20044232

5. Berardesca, E., Farage, M., Maibach, H. Sensitive skin: An overview. Vol. 35, International Journal of Cosmetic Science. Int J Cosmet Sci; 2012. p. 2–8.

6. Richters, R., Falcone, D., Uzunbajakava, N., Verkruysse, W., Van Erp, P., Van De Kerkhof, P. What is sensitive skin? A systematic literature review of objective measurements. Vol. 28, Skin Pharmacology and Physiology. S. Karger AG; 2014. p. 75–83.

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8. Mayo Clinic. Atopic dermatitis (eczema) [Internet]. 2018 Mar 06. Available at: https://www.mayoclinic.org/diseases-conditions/atopic-dermatitis-eczema/symptoms- causes/syc-20353273

9. MedlinePlus. Oily Skin [Internet]. [Cited 2020 Feb 19]. Available at: https://medlineplus.gov/ency/article/002043.htm

10. Mayo Clinic. Peeling skin [Internet]. 2018 Apr 06 [cited 2020 Feb 19]. Available at: https://www.mayoclinic.org/symptoms/peeling-skin/basics/causes/sym-20050672

11. Mayo Clinic. Slide show: Common skin rashes [Internet]. 2019 Sep 28 Available at: https://www.mayoclinic.org/skin-rash/sls-20077087?s=1

12. Mayo Clinic. Moles [Internet]. 2019 Nov 19 [cited 2020 Feb 19]. Available at: https://www.mayoclinic.org/diseases-conditions/moles/symptoms-causes/syc-20375200